https://hades.mech.northwestern.edu//api.php?action=feedcontributions&feedformat=atom&user=MattTMech - User contributions [en]2026-05-13T15:58:25ZUser contributionsMediaWiki 1.43.8https://hades.mech.northwestern.edu//index.php?title=File:DC09MotorControllerCode.zip&diff=14161File:DC09MotorControllerCode.zip2009-08-25T16:30:29Z<p>MattT: Note this code is in rough format with few comments. The principles are guaranteed to work, but it may take time looking at what the code to understand everything. Rewriting sections may be required, depending on your application.</p>
<hr />
<div>Note this code is in rough format with few comments. The principles are guaranteed to work, but it may take time looking at what the code to understand everything. Rewriting sections may be required, depending on your application.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=I2C_Motor_Controller&diff=14159I2C Motor Controller2009-08-25T16:15:04Z<p>MattT: </p>
<hr />
<div>This design is intended as a cost effective, readily available motor controller solution capable of handling multiple controllers from one master device in a logical, powerful and easy to use interface.<br />
<br />
This solution is best suited to drive DC brush motors at encoder rates up to and exceeding 2 MHz. Motor positions are measured with hardware quadrature encoding to achieve this high rate. A built in PID controller with adjustable gains is used to control each motor to be flexible enough for any choice of motor.<br />
<br />
See the datasheet [[Media:I2CMotorController.PDF|'''here''']] for more information about using this I2C motor controller.<br />
<br />
Download zip file of code [[Media:I2CMotorControllerCode.zip|'''here''']]<br />
<br />
Code used on the final Team Banzai Design Competition 2009 robot can be found [[Media:DC09MotorControllerCode.zip|'''here''']] as well. This code uses two PIC18F2431 chips with built in QEI(quadrature) modules. This portion of the slave code can be rewritten to use the LS7081 chips with PIC18F4520 controllers, but in its current state will not work for these chips. The code tracks trapezoidal motion profiles and may not be appropriate for motors will lower than 500CPR resolution. This code in its current state is <b>untested</b>, but the tracking, communication, and polling algorithms make it a good guide in differential drive mobile robotics control.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=I2C_Motor_Controller&diff=14158I2C Motor Controller2009-08-25T16:14:44Z<p>MattT: </p>
<hr />
<div>This design is intended as a cost effective, readily available motor controller solution capable of handling multiple controllers from one master device in a logical, powerful and easy to use interface.<br />
<br />
This solution is best suited to drive DC brush motors at encoder rates up to and exceeding 2 MHz. Motor positions are measured with hardware quadrature encoding to achieve this high rate. A built in PID controller with adjustable gains is used to control each motor to be flexible enough for any choice of motor.<br />
<br />
See the datasheet [[Media:I2CMotorController.PDF|'''here''']] for more information about using this I2C motor controller.<br />
<br />
Download zip file of code [[Media:I2CMotorControllerCode.zip|'''here''']]<br />
<br />
Code used on the final Team Banzai Design Competition 2009 robot can be found [[Media:DC09MotorControllerCode.zip|'''here''']] as well. This code uses two PIC18F2431 chips with built in QEI(quadrature) modules. This portion of the slave code can be rewritten to use the LS7081 chips with PIC18F4520 controllers, but in its current state will not work for these chips. The code tracks trapezoidal motion profiles and may not be appropriate for motors will lower than 500CPR resolution. This code in its current state is <b>untested<\b>, but the tracking, communication, and polling algorithms make it a good guide in differential drive mobile robotics control.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Actuators_Available_in_the_Mechatronics_Lab&diff=13362Actuators Available in the Mechatronics Lab2009-06-09T21:40:05Z<p>MattT: /* DC Motors (with gearheads and encoders) */</p>
<hr />
<div>[[image:all-actuators-captions-small.jpg|right]]<br />
<br />
We have acquired a number of actuators that are appropriately sized for<br />
many mechatronics projects. These are the "standard" lab actuators.<br />
You are welcome to borrow them for your project and return them when<br />
you are finished. In addition to the actuators mentioned below, we<br />
have a number of other actuators that we have acquired over the years<br />
that you are welcome to borrow.<br />
<br />
For your particular project, it may be best to spec out and buy a<br />
particular type and size of actuator. If your specifications are not<br />
too critical, however, the actuators below will allow you to get<br />
started right away.<br />
<br />
<br />
__TOC__<br />
<br />
<br />
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<br />
<br />
<br />
==DC Motors (with gearheads and encoders)==<br />
<br />
There are many types of DC motors, but our favorites are brushed<br />
permanent magnet DC motors for their power, price, ubiquity, and<br />
simplicity. Simply put a voltage across the two motor terminals, and<br />
the motor spins. (You can learn about the [[Brushed DC Motor Theory| theory]] of how a brushed DC <br />
motor works and suggested methods<br />
for driving a DC motor elsewhere on this wiki.) <br />
<br />
One problem is that most DC motors tend to rotate at very high speeds,<br />
typically several thousand RPM or more. This is too fast for most<br />
mechatronics applications. Also, they tend to have too little torque.<br />
Both of these problems can be solved by the use of gears on the output<br />
shaft of the motor. If the motor has an N:1 gearhead on its output<br />
shaft (where N>1, typically), then the output shaft of the gearhead<br />
reduces the speed of the motor by a factor of N and increases the<br />
torque of the motor by a factor of N. (You can learn more<br />
about how [[Gears|gears]] work including other issues<br />
they introduce, such as gearhead efficiency and backlash.)<br />
<br />
Another issue is how to determine how far the motor has rotated. You need<br />
''feedback'' from the motor. There are many ways to do this, using<br />
encoders, potentiometers, and tachometers. The most common way to get angle<br />
feedback is through the use of encoders. An encoder is typically attached<br />
to a motor shaft and produces pulses that encode the shaft rotation angle.<br />
These pulses can be read in by the encoder inputs of the Mechatronics Lab<br />
PC/104 stacks.<br />
<br />
So, perhaps the most versatile kind of actuator is a DC motor with a gearhead and an<br />
encoder. Below are some that we keep in the lab. Sometimes DC motors<br />
with gearheads and encoders can be purchased through surplus outlets at<br />
great prices, for prices less than any of the single components (motor,<br />
gearhead, encoder) could be purchased individually. That's how many<br />
copies of the actuators below were purchased. If you see a great<br />
deal on a nice-sized motor plus gearhead plus encoder, of which many<br />
copies can be purchased, let us know!<br />
<br />
===6W Maxon motor with 6:1 gearhead and 100 line encoder===<br />
<br />
<br />
[[image:maxon-small2.jpg|right]]<br />
<br />
<br />
'''Summary:'''<br />
* 24 V, 41.5 ohms resistance, max current 0.58 Amps<br />
* max torque: 0.15 Nm (approx)<br />
* max speed: 600 RPM (approx)<br />
* encoder: 600 counts/rev at output shaft, 2400 counts/rev in 4x decoding mode<br />
<br />
<br />
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<br />
The motor is rated at 24 volts, giving a no-load (maximum)<br />
speed of 3990 RPM (about 418 radians/sec) and a (maximum) stall torque of 31.9 mNm (milli<br />
Newton meters). The terminal resistance (the resistance through the<br />
motor windings) is 41.5 ohms. This means if you put 24 V across it,<br />
the maximum current that it will draw is 24/41.5 = 0.58 Amps. This<br />
maximum current occurs when the motor is stalled and generating its<br />
maximum torque. Motor torque is proportional to the motor current by<br />
the constant of proportionality called the ''torque constant'',<br />
which is different for every motor.<br />
<br />
The motor is called a 6 Watt motor because that is the maximum<br />
electrical power (current times voltage) that can be put into the<br />
motor on a continuous basis. Beyond this power level, the amount of<br />
power dissipated by the resistance of the motor windings will cause<br />
the windings to heat up unacceptably. (It is fine to overpower the<br />
motor intermittently, allowing the coils to cool so that the average<br />
power does not exceed the rated power.) At this operating point, <br />
the motor draws 244 mA, giving 24 V x 0.244 A = 5.86 W electrical input<br />
power. At this operating point, the speed of the motor is approximately<br />
1689 RPM, or 177 radians/sec, and the torque of the motor is 13.5 mNm,<br />
giving 177 rad/sec x 0.0135 Nm = 2.39 W of mechanical output power,<br />
giving a power-conversion efficiency of about 41% at this operating point.<br />
The maximum efficiency of the motor is 70%, which occurs at a higher<br />
speed and lower torque. The maximum mechanical power you can get out<br />
of the motor is (1/2 max torque) x (1/2 max speed) = 3.33 W. This is<br />
beyond the continuous operation recommendation, but it is fine to<br />
run it for short periods at this operating point.<br />
<br />
Often you will want to run the motor at lower voltages, for instance<br />
at 12 V, instead of the rated 24 V. In this case just multiply the<br />
max current, speed, and torques by the factor 12/24 = 1/2. In particular,<br />
the maximum output power will be only (1/2) x (1/2) = 1/4 the maximum at 24 V.<br />
<br />
This actuator comes with a 6:1 spur gearhead, which increases the<br />
torque available at the gearhead's output shaft by a factor of 6 and<br />
decreases the speed by a factor of 6. (In this ideal case, the<br />
power at the gearhead's output shaft is equal to the power at the input.<br />
In practice, gearheads have an efficiency also; the maximum<br />
efficiency of the gearhead here is 81%. This reduces the torque<br />
available.)<br />
<br />
In summary, then, if your application requires no more than about 6 x<br />
31.9 mNm = 0.19 Nm maximum torque, 3990 RPM / 6 = 665 RPM max speed,<br />
and 3.3 W max mechanical power, this may be the motor for you.<br />
Reduce those values by a factor of 1/2, 1/2, and 1/4, respectively, if<br />
you are operating the motor with 12 V max instead of 24 V max.<br />
<br />
This actuator also comes with a 100 line single-ended incremental optical encoder,<br />
with outputs A+ and B+. There is no index channel. The encoder is<br />
attached to the motor. Each of the A+ and B+ channels makes 100 pulses<br />
per revolution of the motor, or 6 x 100 = 600 pulses per revolution of<br />
the output shaft of the gearhead. This means the encoder provides<br />
360 deg / 600 pulses = 0.6 deg/pulse resolution when the pulses are <br />
decoded with the 1x scheme, or 0.15 deg/pulse resolution with the 4x<br />
decoding scheme.<br />
<br />
Information about the Maxon motor is given in this [[Media:maxon-2140-specs.pdf|data sheet]] which includes <br />
other motors in this family (ours is the 24V version)<br />
and this [[Media:maxon-our-specific-motor.pdf|data sheet]] which gives only<br />
the information on this motor. Information on the 6:1 gearhead can be found <br />
[[Media:maxon-gearhead.pdf|here]]. The encoder pin-out is indicated below:<br />
<br />
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<br />
[[image:encoder-maxon.jpg|right]]<br />
<br />
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<br />
The encoder comes with a 4-connector ribbon cable, corresponding to GND, Channel A, Vcc (usually +5V), and Channel B, as<br />
shown on the left. Here the ribbon cable is broken out into a 10-pin connector (which we have in the lab). The connector<br />
above is made to work with the PC/104 stacks, and the pin-out is shown. Always make sure you have the right connections<br />
for your encoder so you don't damage it!<br />
<br />
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<br />
===Pittman GM8224 motor with 19.5:1 gearhead and 500 line encoder===<br />
<br />
[[image:pittman-small.jpg|right]]<br />
<br />
If you need more power than the motor above, this gearmotor may be a good choice.<br />
As an added bonus, it provides much higher encoder resolution.<br />
<br />
'''Summary:'''<br />
* 24 V, 4.33 ohms resistance, max current 5.54 Amps<br />
* max torque: 2 Nm (approx)<br />
* max speed: 500 RPM (approx)<br />
* encoder: 9750 counts/rev at output shaft, 39,000 counts/rev in 4x decoding mode<br />
<br />
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<br />
This motor is also rated at 24 V, with a terminal resistance of 4.33 ohms,<br />
giving a stall (maximum) current of 5.54 Amps. The stall torque of the motor<br />
itself is 0.1186 Nm<br />
and the no-load (maximum) speed is 10,158 RPM (1064 radians/sec). The<br />
recommended maximum continuous torque is 0.0185 Nm which occurs at <br />
8573 RPM (898 radians/sec). Taken together, the maximum motor mechanical power<br />
is (1/2 Tmax) x (1/2 nmax) = 31.5 W and the maximum recommended continuous<br />
mechanical power is 16.6 W. The maximum electrical input power occurs when<br />
the motor is stalled (or starting) and is 24 V x 5.54 A = 133 W. If you<br />
operate the motor at a smaller voltage V2, then multiply the currents, speeds,<br />
and torques above by a factor V2/24 and the power by a factor of (V2/24)^2.<br />
<br />
This motor has a 19.5:1 gearhead with a power conversion efficiency of 73%. <br />
Ignoring the efficiency for the moment, the 19.5:1 gearbox means that this<br />
actuator may be appropriate if our application calls for no more than a <br />
maximum speed of 10,158 RPM / 19.5 = 521 RPM and a maximum torque of<br />
0.1186 Nm x 19.5 = 2.3 Nm. In other words, the output shaft speed is similar<br />
to the Maxon gearmotor above, but with about 10 times the torque. <br />
<br />
This motor comes with a 500 line encoder attached to the motor shaft. The<br />
encoder has output channels A+ and B+ (no index pulse). This means that<br />
the encoder provides 500 x 19.5 = 9750 pulses per revolution of the output shaft.<br />
In the 4x decoding mode, this gives 39,000 counts per revolution, or a resolution<br />
of 360/39,000 = 0.00923 degrees.<br />
<br />
We also have a limited number of Pittman GM8712 motors with a 19.5:1 gearhead<br />
and 512 line encoder. These motors are also rated at 24V but have a higher<br />
terminal resistance of 12.1 ohms, giving a maximum current of 24/12.1 = 1.99 Amps.<br />
They have a maximum speed of 7847 RPM and maximum torque of 0.052 Nm before the<br />
gearhead, or (ignoring gearhead efficiency) 402 RPM and 1.01 Nm after the<br />
gearhead. This motor is less powerful and draws less current, which may<br />
be appropriate for some applications.<br />
The encoder provides 9984 pulses per revolution of the output shaft<br />
of the gearhead, or 360/(4 x 9984) = 0.009 degrees resolution in 4x decoding mode.<br />
<br />
See the [[Media:pittmangearmotor.pdf|data sheet]] for more detailed<br />
information on these Pittman 8224 and 8712 gearmotors. The 8712 is not treated<br />
explicitly, but is believed to be similar to the 8722.<br />
<br />
The quadrature encoder has four wires: black (GND), red (+5V), and blue and yellow as <br />
channels A and B.<br />
<br />
===Pittman 700935 motor with 500 line encoder===<br />
<br />
[[image:Pittmann700935.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* Speed: 5000 RPM<br />
* Voltage: 24 V<br />
* Continuous Torque: unknown<br />
* Stall Current: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 2000 CPR in 4X mode at output shaft<br />
* Gearhead: N/A<br />
* Mass: 410 grams<br />
* Length: 4.75 inches<br />
* Motor Constant: unknown<br />
<br />
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<br />
<br />
===Pittman GM9413J820 motor with 500 line encoder===<br />
<br />
[[image:PittmannGM9413J820.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* Speed: 85 RPM<br />
* Voltage: 24 V<br />
* Continuous Torque: unknown<br />
* Stall Current: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 39,400 CPR in 4X mode at output shaft<br />
* Gearhead: 19.7:1<br />
* Mass: 510 grams<br />
* Length: 4.75 inches<br />
* Motor Constant: unknown<br />
<br />
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<br />
===Faulhaber 1524E006S motor with 141:1 gearhead and HES164A magnetic quadrature encoder===<br />
<br />
[[image:faulhaber.png|right]]<br />
<br />
'''Summary:'''<br />
* motor rated at 6V, 12 ohms resistance (motor: 1524E006S123, where 123 is a special order)<br />
* 141:1 gearhead (gearhead: 15/5S141:1K832)<br />
* max speed at 6V: approximately 80 RPM at gearhead output<br />
* quadrature encoder with 1 line per motor revolution, or 141 x 4 = 564 counts/rev at output shaft in 4x decoding mode (encoder: HES164A)<br />
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<br />
This little motor is the right size, speed, and torque for small wheeled mobile robots.<br />
Ours were bought surplus from [http://www.bgmicro.com bgmicro.com]. This <br />
[http://www.robotroom.com/FaulhaberGearmotor.html page] by<br />
David Cook has a lot of great information on this motor + gearhead + encoder combination.<br />
More info can be found in this [[Media:faulhaber-datasheet.pdf|data sheet]] from Faulhaber,<br />
though our exact model encoder and motor are not listed. The gearhead has a right-angle<br />
drive at the output.<br />
<br />
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<br />
[[image:faulhaber-pinout.jpg|right]]<br />
<br />
The pins on the connector are (see figure at right):<br />
<br />
<br />
1. Motor + <br><br />
2. +5V (or similar) to power the encoder<br><br />
3. Encoder channel A<br><br />
4. Encoder channel B<br><br />
5. GND for the encoder<br><br />
6. Motor -<br />
<br />
<br />
Encoder channels A and B can sink (connect to ground) up to probably 25mA like most Hall sensors. There is only a a weak pull-up resistor inside, perhaps 10K, so they can only source (connect to +5) about 2mA. If you find the logic high signal from the encoder channel is not close enough to +5, which can happen even due to loading by an LED, you may want to add an external pull-up resistor from each encoder channel to +5. 470ohms is a good choice.<br />
<br />
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<br />
[[image:faulhaber-wheel.jpg|right]]<br />
<br />
These [http://www.solarbotics.com/products/gmpw/ wheels] can be used with the motor (with the<br />
right-angle drive) if you drill out the center of the wheel with a 9/32" bit (approximately). Then you<br />
should get a nice tight press-fit. We have some of these wheels in the lab. This press-fit is not <br />
suitable for high-torque applications, though; the shaft may begin to slip.<br />
<br />
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<br />
===Globe motor with 187.68:1 gearhead and 500 line encoder===<br />
<br />
[[image:globe-motor.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* motor rated at 12V, 21 ohms resistance (0.57 A stall current)<br />
* 187.68:1 gearhead for high torque and low speed<br />
* max speed at 12V: approximately 17 RPM at gearhead output (no load speed, motor alone: approx 3000 RPM)<br />
* torque constant (motor alone): approximately 34 mNm/A (or 3.6 mV/RPM)<br />
* stall torque: motor alone: 0.019 Nm; with gearhead 2.4 Nm (based on torque multiplier of 125, less than the 187 gear ratio due to efficiency losses)<br />
* quadrature encoder with 500 lines per motor revolution, or 500 x 4 x 187.68 = 375,360 counts/rev at output shaft in 4x decoding mode (encoder: HEDS-5505 A04)<br />
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<br />
This small motor combines with a high resolution encoder and a high gear ratio gearbox to give a high torque, low speed actuator with high resolution position sensing (and velocity sensing by finite differencing). The stall torque for this gearmotor (at 12 V) is approximately the same as that for the Pittman GM8224 gearmotor (at 24 V), but the max speed for the PIttman gearmotor is 20 times higher. The pin-out for the encoder is shown below. You can attach to the encoder using a Samtec IDSS-05-D-12.00 cable (shown in the middle below; order directly from [http://www.samtec.com Samtec], about $3.50 each and we have several in the lab), a less-expensive 5-pin cable CAB2154 from [https://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=12868 bgmicro] (we have several in the lab), or you can make your own cable using stranded wires (22 AWG or ribbon cable) crimped or soldered in female Molex terminal pins (Molex series KK 2759, part number WM1114CT-ND on digikey) in a Molex 5 position connector housing (Molex series KK 2695, part number WM1578-ND on digikey), shown at right below. (See [[Making a Molex Connector]] for more details.) The [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder recommends putting a 3.2k pull-up resistor on Channels A and B (i.e., 3.2k resistors from these lines to +5V). The encoder works without these, but the datasheet indicates that you get better rise times on the encoder signals at high speeds when the pull-up resistors are added.<br />
<br />
[[image:globe-encoder-annotated.jpg|300px]]<br />
[[image:globe-encoder-cable.jpg|200px]]<br />
[[image:globe-encoder-cable-molex.jpg|200px]]<br />
<br />
If you want a higher-speed (up to 3000 RPM at 12V) lower-torque actuator, you can try removing the gearbox. This task takes a bit of work and may require a bit of machining. See [[Accessing_Pinion_of_Globe_Motor|here]]. This page also shows how to remove the encoder, in case you want to use it in a project without the motor.<br />
<br />
The two motor power leads are wound through a ferrite toroid to suppress EMI "noise."<br />
<br />
Here you can find a [[Media:globe-cad.pdf|cad file]] describing this actuator, a [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder, and a [[Media:idss-connector.pdf|datasheet]] for the Samtec IDSS-05-D-12.00 connector.<br />
<br />
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<br />
===GM3 and GM9 Gearmotors===<br />
<br />
[[image:GM3.png|right]]<br />
<br />
'''Summary:''' (GM3 pictured at right)<br />
* rated at 6V, approx 10 ohms resistance<br />
* 224:1 gearhead (GM3) or 143:1 gearhead (GM9)<br />
* max speed at 6V approximately 43 RPM (GM3) or 84 RPM (GM9)<br />
* stall torque at 6V approximately 73 oz-in (GM3) or 52 oz-in (GM9)<br />
* no encoder installed, but can be modified to add one; see [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|here]]<br />
* size: 70 x 22.5 x 37 mm<br />
<br clear=all><br />
<br />
These highly-geared motors can be bought new at [http://www.solarbotics.com solarbotics.com] or [http://www.hobbyengineering.com hobbyengineering.com]. These motors work with these [http://www.solarbotics.com/products/gmpw/ wheels], which we have in<br />
the lab. The motors do not come with encoders, but you can [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|add one yourself]],<br />
similar to the magnetic encoder on the Faulhaber motor above.<br />
<br />
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<br />
==Stepper Motors==<br />
<br />
Stepper motors move in discrete steps. The controller energizes electromagnet<br />
coils, and the motor's rotor rotates to the nearest equilibrium point. By<br />
proper sequencing of which coils are energized, the motor rotates as desired<br />
(and, if the rotation is fast enough, may simply pass through the equilibrium<br />
points without stopping). <br />
<br />
One nice thing about stepper motors is that they do not require<br />
feedback; we know how far the motor has rotated, because we commanded<br />
the motion. This becomes a problem if we try to rotate the motor too<br />
fast, or if the load is larger than expected --- the motor may not<br />
actually do what we commanded. Stepper motors are a <br />
good choice for relatively low-torque applications where the loads<br />
are consistent, so we can be assured our commanded motions are followed.<br />
<br />
===Jameco 163395 8.4V bipolar stepper motor===<br />
<br />
[[image:small-stepper.jpg|right]]<br />
<br />
Although this motor is rated at 8.4V, it is possible<br />
to run it at lower or slightly higher voltages.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 8.4V, 2 phases, 30 ohms resistance, 280 mA current<br />
* holding torque: 0.081 Nm (coils energized)<br />
* detent torque: 0.0037 Nm (coils off)<br />
* size: 1.64" motor diameter, 1.2" motor height<br />
* shaft: 0.29" x 0.155" diameter<br />
* mass: 0.24 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-163395.pdf|data sheet]].<br />
There are four leads, two for each independent coil.<br />
<br />
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<br />
===Jameco 162026CX 12V unipolar stepper motor===<br />
<br />
[[image:stepper-small.jpg|right]]<br />
<br />
If you need more holding torque, this stepper may be a<br />
good choice.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 12V, 4 phases, 20 ohms resistance, 600 mA current<br />
* holding torque: 0.588 Nm (coils energized)<br />
* detent torque: 0.071 Nm (coils off)<br />
* size: 2.2" motor diameter, 2.0" motor height<br />
* shaft: 1" x 0.25" diameter<br />
* mass: 0.65 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-162026.pdf|data sheet]] (ours is the <br />
57BYG084). There are six leads, three for each independent<br />
coil.<br />
<br />
<br clear=all><br />
<br />
==RC Servo Motors==<br />
<br />
RC servos are convenient for positioning applications that require<br />
significant torque, not much speed, and only moderate positioning<br />
precision. They take three connections, power (+5V, typically),<br />
ground, and a pulsing signal that tells the motor the desired angle (typically a<br />
pulse of 0.5 - 3 ms every 20 ms or so, where the duration of the pulse<br />
indicates the desired angle of the motor).<br />
Inside the motor is a potentiometer that senses the actual angle of<br />
the motor output shaft and a feedback controller that tries to make<br />
the motor angle match that specified by the pulsed signal. There is<br />
also a large gear ratio such that the motor provides high torque at<br />
low speed. Most RC servos have limited angle range, like 180 degrees,<br />
due to the angle-sensing potentiometer.<br />
<br />
<br />
===Futaba S3004 standard ball bearing RC servo motor===<br />
<br />
[[image:RC-servo-small.jpg|right]]<br />
<br />
* motor rotation: 180 degrees<br />
* speed: 60 degrees in 0.23 sec at 4.8V, 0.19 sec at 6V<br />
* torque: 0.31 Nm at 4.8V, 0.4 Nm at 6V<br />
* size: 1.4" height, 0.8" width<br />
* mass: 37.2 g<br />
<br />
These were purchased from Tower Hobbies, part number LM1954.<br />
Higher torque versions are also available.<br />
<br />
<br clear=all><br />
<br />
==Solenoids==<br />
<br />
<br />
<br />
Solenoids are simple on-off actuators consisting of a plunger moving in an<br />
electromagnetic field. If you power the electromagnet, the plunger is<br />
"pushed" or "pulled" a particular stroke length, and if you unpower the<br />
coil, the plunger returns to its original position, usually by a return <br />
spring or gravity. These are simple to control and useful for applications<br />
where the actuator only has to take one of two positions. <br />
<br />
<br />
We stock two solenoids (in addition to many random ones) which are basically<br />
the same, except one is a "pull type" solenoid and the other is a "push type."<br />
<br />
===Jameco 262262 (pull) and 262271 (push) 12V open frame solenoid===<br />
<br />
[[image:solenoids-small.jpg|right]]<br />
<br />
* 12 V, 36 ohm resistance, 333 mA<br />
* holding force: 0.5 N<br />
* stroke: 6 mm<br />
* size: 1.5" length x 1.0" x 0.8" diameter<br />
* shaft diameter: 0.310"<br />
* mass: 96 g<br />
<br />
You can find a data sheet [[Media:jameco-solenoid-262262.pdf|here]].<br />
You can attach a lever (or other mechanical transformer) to the plunger to<br />
get more stroke and less force, or more force and less stroke. If no lever<br />
will meet your specs,<br />
then you will need another solenoid.<br />
<br />
<br />
==AC Motors==<br />
<br />
[[image:ac-servo-small.jpg|right]]<br />
<br />
Some projects need more power than any of the actuators above can<br />
provide. In that case, you may be able to use a Yaskawa AC motor.<br />
These are technically in the Laboratory for Intelligent Mechanical<br />
Systems, but they are available for Mechatronics use. These should<br />
not be a first choice, as (1) they can be dangerous due to their high<br />
power, and (2) they limit the mobility of your project as they must be<br />
plugged into the wall to get 110V AC. You can find information<br />
on these motors and their amplifiers<br />
[http://www.mech.northwestern.edu/courses/433/Writeups/YaskawaMotors/YakawaACservomotors.htm here].</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Actuators_Available_in_the_Mechatronics_Lab&diff=13361Actuators Available in the Mechatronics Lab2009-06-09T21:31:45Z<p>MattT: </p>
<hr />
<div>[[image:all-actuators-captions-small.jpg|right]]<br />
<br />
We have acquired a number of actuators that are appropriately sized for<br />
many mechatronics projects. These are the "standard" lab actuators.<br />
You are welcome to borrow them for your project and return them when<br />
you are finished. In addition to the actuators mentioned below, we<br />
have a number of other actuators that we have acquired over the years<br />
that you are welcome to borrow.<br />
<br />
For your particular project, it may be best to spec out and buy a<br />
particular type and size of actuator. If your specifications are not<br />
too critical, however, the actuators below will allow you to get<br />
started right away.<br />
<br />
<br />
__TOC__<br />
<br />
<br />
<br clear=all><br />
<br />
<br />
<br />
==DC Motors (with gearheads and encoders)==<br />
<br />
There are many types of DC motors, but our favorites are brushed<br />
permanent magnet DC motors for their power, price, ubiquity, and<br />
simplicity. Simply put a voltage across the two motor terminals, and<br />
the motor spins. (You can learn about the [[Brushed DC Motor Theory| theory]] of how a brushed DC <br />
motor works and suggested methods<br />
for driving a DC motor elsewhere on this wiki.) <br />
<br />
One problem is that most DC motors tend to rotate at very high speeds,<br />
typically several thousand RPM or more. This is too fast for most<br />
mechatronics applications. Also, they tend to have too little torque.<br />
Both of these problems can be solved by the use of gears on the output<br />
shaft of the motor. If the motor has an N:1 gearhead on its output<br />
shaft (where N>1, typically), then the output shaft of the gearhead<br />
reduces the speed of the motor by a factor of N and increases the<br />
torque of the motor by a factor of N. (You can learn more<br />
about how [[Gears|gears]] work including other issues<br />
they introduce, such as gearhead efficiency and backlash.)<br />
<br />
Another issue is how to determine how far the motor has rotated. You need<br />
''feedback'' from the motor. There are many ways to do this, using<br />
encoders, potentiometers, and tachometers. The most common way to get angle<br />
feedback is through the use of encoders. An encoder is typically attached<br />
to a motor shaft and produces pulses that encode the shaft rotation angle.<br />
These pulses can be read in by the encoder inputs of the Mechatronics Lab<br />
PC/104 stacks.<br />
<br />
So, perhaps the most versatile kind of actuator is a DC motor with a gearhead and an<br />
encoder. Below are some that we keep in the lab. Sometimes DC motors<br />
with gearheads and encoders can be purchased through surplus outlets at<br />
great prices, for prices less than any of the single components (motor,<br />
gearhead, encoder) could be purchased individually. That's how many<br />
copies of the actuators below were purchased. If you see a great<br />
deal on a nice-sized motor plus gearhead plus encoder, of which many<br />
copies can be purchased, let us know!<br />
<br />
===6W Maxon motor with 6:1 gearhead and 100 line encoder===<br />
<br />
<br />
[[image:maxon-small2.jpg|right]]<br />
<br />
<br />
'''Summary:'''<br />
* 24 V, 41.5 ohms resistance, max current 0.58 Amps<br />
* max torque: 0.15 Nm (approx)<br />
* max speed: 600 RPM (approx)<br />
* encoder: 600 counts/rev at output shaft, 2400 counts/rev in 4x decoding mode<br />
<br />
<br />
<br clear=all><br />
<br />
The motor is rated at 24 volts, giving a no-load (maximum)<br />
speed of 3990 RPM (about 418 radians/sec) and a (maximum) stall torque of 31.9 mNm (milli<br />
Newton meters). The terminal resistance (the resistance through the<br />
motor windings) is 41.5 ohms. This means if you put 24 V across it,<br />
the maximum current that it will draw is 24/41.5 = 0.58 Amps. This<br />
maximum current occurs when the motor is stalled and generating its<br />
maximum torque. Motor torque is proportional to the motor current by<br />
the constant of proportionality called the ''torque constant'',<br />
which is different for every motor.<br />
<br />
The motor is called a 6 Watt motor because that is the maximum<br />
electrical power (current times voltage) that can be put into the<br />
motor on a continuous basis. Beyond this power level, the amount of<br />
power dissipated by the resistance of the motor windings will cause<br />
the windings to heat up unacceptably. (It is fine to overpower the<br />
motor intermittently, allowing the coils to cool so that the average<br />
power does not exceed the rated power.) At this operating point, <br />
the motor draws 244 mA, giving 24 V x 0.244 A = 5.86 W electrical input<br />
power. At this operating point, the speed of the motor is approximately<br />
1689 RPM, or 177 radians/sec, and the torque of the motor is 13.5 mNm,<br />
giving 177 rad/sec x 0.0135 Nm = 2.39 W of mechanical output power,<br />
giving a power-conversion efficiency of about 41% at this operating point.<br />
The maximum efficiency of the motor is 70%, which occurs at a higher<br />
speed and lower torque. The maximum mechanical power you can get out<br />
of the motor is (1/2 max torque) x (1/2 max speed) = 3.33 W. This is<br />
beyond the continuous operation recommendation, but it is fine to<br />
run it for short periods at this operating point.<br />
<br />
Often you will want to run the motor at lower voltages, for instance<br />
at 12 V, instead of the rated 24 V. In this case just multiply the<br />
max current, speed, and torques by the factor 12/24 = 1/2. In particular,<br />
the maximum output power will be only (1/2) x (1/2) = 1/4 the maximum at 24 V.<br />
<br />
This actuator comes with a 6:1 spur gearhead, which increases the<br />
torque available at the gearhead's output shaft by a factor of 6 and<br />
decreases the speed by a factor of 6. (In this ideal case, the<br />
power at the gearhead's output shaft is equal to the power at the input.<br />
In practice, gearheads have an efficiency also; the maximum<br />
efficiency of the gearhead here is 81%. This reduces the torque<br />
available.)<br />
<br />
In summary, then, if your application requires no more than about 6 x<br />
31.9 mNm = 0.19 Nm maximum torque, 3990 RPM / 6 = 665 RPM max speed,<br />
and 3.3 W max mechanical power, this may be the motor for you.<br />
Reduce those values by a factor of 1/2, 1/2, and 1/4, respectively, if<br />
you are operating the motor with 12 V max instead of 24 V max.<br />
<br />
This actuator also comes with a 100 line single-ended incremental optical encoder,<br />
with outputs A+ and B+. There is no index channel. The encoder is<br />
attached to the motor. Each of the A+ and B+ channels makes 100 pulses<br />
per revolution of the motor, or 6 x 100 = 600 pulses per revolution of<br />
the output shaft of the gearhead. This means the encoder provides<br />
360 deg / 600 pulses = 0.6 deg/pulse resolution when the pulses are <br />
decoded with the 1x scheme, or 0.15 deg/pulse resolution with the 4x<br />
decoding scheme.<br />
<br />
Information about the Maxon motor is given in this [[Media:maxon-2140-specs.pdf|data sheet]] which includes <br />
other motors in this family (ours is the 24V version)<br />
and this [[Media:maxon-our-specific-motor.pdf|data sheet]] which gives only<br />
the information on this motor. Information on the 6:1 gearhead can be found <br />
[[Media:maxon-gearhead.pdf|here]]. The encoder pin-out is indicated below:<br />
<br />
<br clear=all><br />
<br />
[[image:encoder-maxon.jpg|right]]<br />
<br />
<br clear=all><br />
<br />
The encoder comes with a 4-connector ribbon cable, corresponding to GND, Channel A, Vcc (usually +5V), and Channel B, as<br />
shown on the left. Here the ribbon cable is broken out into a 10-pin connector (which we have in the lab). The connector<br />
above is made to work with the PC/104 stacks, and the pin-out is shown. Always make sure you have the right connections<br />
for your encoder so you don't damage it!<br />
<br />
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<br />
===Pittman GM8224 motor with 19.5:1 gearhead and 500 line encoder===<br />
<br />
[[image:pittman-small.jpg|right]]<br />
<br />
If you need more power than the motor above, this gearmotor may be a good choice.<br />
As an added bonus, it provides much higher encoder resolution.<br />
<br />
'''Summary:'''<br />
* 24 V, 4.33 ohms resistance, max current 5.54 Amps<br />
* max torque: 2 Nm (approx)<br />
* max speed: 500 RPM (approx)<br />
* encoder: 9750 counts/rev at output shaft, 39,000 counts/rev in 4x decoding mode<br />
<br />
<br clear=all><br />
<br />
This motor is also rated at 24 V, with a terminal resistance of 4.33 ohms,<br />
giving a stall (maximum) current of 5.54 Amps. The stall torque of the motor<br />
itself is 0.1186 Nm<br />
and the no-load (maximum) speed is 10,158 RPM (1064 radians/sec). The<br />
recommended maximum continuous torque is 0.0185 Nm which occurs at <br />
8573 RPM (898 radians/sec). Taken together, the maximum motor mechanical power<br />
is (1/2 Tmax) x (1/2 nmax) = 31.5 W and the maximum recommended continuous<br />
mechanical power is 16.6 W. The maximum electrical input power occurs when<br />
the motor is stalled (or starting) and is 24 V x 5.54 A = 133 W. If you<br />
operate the motor at a smaller voltage V2, then multiply the currents, speeds,<br />
and torques above by a factor V2/24 and the power by a factor of (V2/24)^2.<br />
<br />
This motor has a 19.5:1 gearhead with a power conversion efficiency of 73%. <br />
Ignoring the efficiency for the moment, the 19.5:1 gearbox means that this<br />
actuator may be appropriate if our application calls for no more than a <br />
maximum speed of 10,158 RPM / 19.5 = 521 RPM and a maximum torque of<br />
0.1186 Nm x 19.5 = 2.3 Nm. In other words, the output shaft speed is similar<br />
to the Maxon gearmotor above, but with about 10 times the torque. <br />
<br />
This motor comes with a 500 line encoder attached to the motor shaft. The<br />
encoder has output channels A+ and B+ (no index pulse). This means that<br />
the encoder provides 500 x 19.5 = 9750 pulses per revolution of the output shaft.<br />
In the 4x decoding mode, this gives 39,000 counts per revolution, or a resolution<br />
of 360/39,000 = 0.00923 degrees.<br />
<br />
We also have a limited number of Pittman GM8712 motors with a 19.5:1 gearhead<br />
and 512 line encoder. These motors are also rated at 24V but have a higher<br />
terminal resistance of 12.1 ohms, giving a maximum current of 24/12.1 = 1.99 Amps.<br />
They have a maximum speed of 7847 RPM and maximum torque of 0.052 Nm before the<br />
gearhead, or (ignoring gearhead efficiency) 402 RPM and 1.01 Nm after the<br />
gearhead. This motor is less powerful and draws less current, which may<br />
be appropriate for some applications.<br />
The encoder provides 9984 pulses per revolution of the output shaft<br />
of the gearhead, or 360/(4 x 9984) = 0.009 degrees resolution in 4x decoding mode.<br />
<br />
See the [[Media:pittmangearmotor.pdf|data sheet]] for more detailed<br />
information on these Pittman 8224 and 8712 gearmotors. The 8712 is not treated<br />
explicitly, but is believed to be similar to the 8722.<br />
<br />
The quadrature encoder has four wires: black (GND), red (+5V), and blue and yellow as <br />
channels A and B.<br />
<br />
===Pittman 700935 motor with 500 line encoder===<br />
<br />
[[image:Pittmann700935.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* Speed: 5000 RPM<br />
* Voltage: 24 V<br />
* Torque: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 2000 CPR in 4X mode at output shaft<br />
* Gearhead: N/A<br />
* Weight: unknown<br />
* Length: unknown<br />
* Motor Constant: unknown<br />
<br />
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<br />
<br />
===Pittman GM9413J820 motor with 500 line encoder===<br />
<br />
[[image:PittmannGM9413J820.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* Speed: 85 RPM<br />
* Voltage: 24 V<br />
* Torque: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 39,400 CPR in 4X mode at output shaft<br />
* Gearhead: 19.7:1<br />
* Weight: unknown<br />
* Length: unknown<br />
* Motor Constant: unknown<br />
<br />
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<br />
===Faulhaber 1524E006S motor with 141:1 gearhead and HES164A magnetic quadrature encoder===<br />
<br />
[[image:faulhaber.png|right]]<br />
<br />
'''Summary:'''<br />
* motor rated at 6V, 12 ohms resistance (motor: 1524E006S123, where 123 is a special order)<br />
* 141:1 gearhead (gearhead: 15/5S141:1K832)<br />
* max speed at 6V: approximately 80 RPM at gearhead output<br />
* quadrature encoder with 1 line per motor revolution, or 141 x 4 = 564 counts/rev at output shaft in 4x decoding mode (encoder: HES164A)<br />
<br clear=all><br />
<br />
This little motor is the right size, speed, and torque for small wheeled mobile robots.<br />
Ours were bought surplus from [http://www.bgmicro.com bgmicro.com]. This <br />
[http://www.robotroom.com/FaulhaberGearmotor.html page] by<br />
David Cook has a lot of great information on this motor + gearhead + encoder combination.<br />
More info can be found in this [[Media:faulhaber-datasheet.pdf|data sheet]] from Faulhaber,<br />
though our exact model encoder and motor are not listed. The gearhead has a right-angle<br />
drive at the output.<br />
<br />
<br clear=all><br />
<br />
[[image:faulhaber-pinout.jpg|right]]<br />
<br />
The pins on the connector are (see figure at right):<br />
<br />
<br />
1. Motor + <br><br />
2. +5V (or similar) to power the encoder<br><br />
3. Encoder channel A<br><br />
4. Encoder channel B<br><br />
5. GND for the encoder<br><br />
6. Motor -<br />
<br />
<br />
Encoder channels A and B can sink (connect to ground) up to probably 25mA like most Hall sensors. There is only a a weak pull-up resistor inside, perhaps 10K, so they can only source (connect to +5) about 2mA. If you find the logic high signal from the encoder channel is not close enough to +5, which can happen even due to loading by an LED, you may want to add an external pull-up resistor from each encoder channel to +5. 470ohms is a good choice.<br />
<br />
<br clear=all><br />
<br />
[[image:faulhaber-wheel.jpg|right]]<br />
<br />
These [http://www.solarbotics.com/products/gmpw/ wheels] can be used with the motor (with the<br />
right-angle drive) if you drill out the center of the wheel with a 9/32" bit (approximately). Then you<br />
should get a nice tight press-fit. We have some of these wheels in the lab. This press-fit is not <br />
suitable for high-torque applications, though; the shaft may begin to slip.<br />
<br />
<br clear=all><br />
<br />
===Globe motor with 187.68:1 gearhead and 500 line encoder===<br />
<br />
[[image:globe-motor.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* motor rated at 12V, 21 ohms resistance (0.57 A stall current)<br />
* 187.68:1 gearhead for high torque and low speed<br />
* max speed at 12V: approximately 17 RPM at gearhead output (no load speed, motor alone: approx 3000 RPM)<br />
* torque constant (motor alone): approximately 34 mNm/A (or 3.6 mV/RPM)<br />
* stall torque: motor alone: 0.019 Nm; with gearhead 2.4 Nm (based on torque multiplier of 125, less than the 187 gear ratio due to efficiency losses)<br />
* quadrature encoder with 500 lines per motor revolution, or 500 x 4 x 187.68 = 375,360 counts/rev at output shaft in 4x decoding mode (encoder: HEDS-5505 A04)<br />
<br clear=all><br />
<br />
This small motor combines with a high resolution encoder and a high gear ratio gearbox to give a high torque, low speed actuator with high resolution position sensing (and velocity sensing by finite differencing). The stall torque for this gearmotor (at 12 V) is approximately the same as that for the Pittman GM8224 gearmotor (at 24 V), but the max speed for the PIttman gearmotor is 20 times higher. The pin-out for the encoder is shown below. You can attach to the encoder using a Samtec IDSS-05-D-12.00 cable (shown in the middle below; order directly from [http://www.samtec.com Samtec], about $3.50 each and we have several in the lab), a less-expensive 5-pin cable CAB2154 from [https://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=12868 bgmicro] (we have several in the lab), or you can make your own cable using stranded wires (22 AWG or ribbon cable) crimped or soldered in female Molex terminal pins (Molex series KK 2759, part number WM1114CT-ND on digikey) in a Molex 5 position connector housing (Molex series KK 2695, part number WM1578-ND on digikey), shown at right below. (See [[Making a Molex Connector]] for more details.) The [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder recommends putting a 3.2k pull-up resistor on Channels A and B (i.e., 3.2k resistors from these lines to +5V). The encoder works without these, but the datasheet indicates that you get better rise times on the encoder signals at high speeds when the pull-up resistors are added.<br />
<br />
[[image:globe-encoder-annotated.jpg|300px]]<br />
[[image:globe-encoder-cable.jpg|200px]]<br />
[[image:globe-encoder-cable-molex.jpg|200px]]<br />
<br />
If you want a higher-speed (up to 3000 RPM at 12V) lower-torque actuator, you can try removing the gearbox. This task takes a bit of work and may require a bit of machining. See [[Accessing_Pinion_of_Globe_Motor|here]]. This page also shows how to remove the encoder, in case you want to use it in a project without the motor.<br />
<br />
The two motor power leads are wound through a ferrite toroid to suppress EMI "noise."<br />
<br />
Here you can find a [[Media:globe-cad.pdf|cad file]] describing this actuator, a [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder, and a [[Media:idss-connector.pdf|datasheet]] for the Samtec IDSS-05-D-12.00 connector.<br />
<br />
<br clear=all><br />
<br />
===GM3 and GM9 Gearmotors===<br />
<br />
[[image:GM3.png|right]]<br />
<br />
'''Summary:''' (GM3 pictured at right)<br />
* rated at 6V, approx 10 ohms resistance<br />
* 224:1 gearhead (GM3) or 143:1 gearhead (GM9)<br />
* max speed at 6V approximately 43 RPM (GM3) or 84 RPM (GM9)<br />
* stall torque at 6V approximately 73 oz-in (GM3) or 52 oz-in (GM9)<br />
* no encoder installed, but can be modified to add one; see [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|here]]<br />
* size: 70 x 22.5 x 37 mm<br />
<br clear=all><br />
<br />
These highly-geared motors can be bought new at [http://www.solarbotics.com solarbotics.com] or [http://www.hobbyengineering.com hobbyengineering.com]. These motors work with these [http://www.solarbotics.com/products/gmpw/ wheels], which we have in<br />
the lab. The motors do not come with encoders, but you can [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|add one yourself]],<br />
similar to the magnetic encoder on the Faulhaber motor above.<br />
<br />
<br clear=all><br />
<br />
==Stepper Motors==<br />
<br />
Stepper motors move in discrete steps. The controller energizes electromagnet<br />
coils, and the motor's rotor rotates to the nearest equilibrium point. By<br />
proper sequencing of which coils are energized, the motor rotates as desired<br />
(and, if the rotation is fast enough, may simply pass through the equilibrium<br />
points without stopping). <br />
<br />
One nice thing about stepper motors is that they do not require<br />
feedback; we know how far the motor has rotated, because we commanded<br />
the motion. This becomes a problem if we try to rotate the motor too<br />
fast, or if the load is larger than expected --- the motor may not<br />
actually do what we commanded. Stepper motors are a <br />
good choice for relatively low-torque applications where the loads<br />
are consistent, so we can be assured our commanded motions are followed.<br />
<br />
===Jameco 163395 8.4V bipolar stepper motor===<br />
<br />
[[image:small-stepper.jpg|right]]<br />
<br />
Although this motor is rated at 8.4V, it is possible<br />
to run it at lower or slightly higher voltages.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 8.4V, 2 phases, 30 ohms resistance, 280 mA current<br />
* holding torque: 0.081 Nm (coils energized)<br />
* detent torque: 0.0037 Nm (coils off)<br />
* size: 1.64" motor diameter, 1.2" motor height<br />
* shaft: 0.29" x 0.155" diameter<br />
* mass: 0.24 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-163395.pdf|data sheet]].<br />
There are four leads, two for each independent coil.<br />
<br />
<br clear=all><br />
<br />
===Jameco 162026CX 12V unipolar stepper motor===<br />
<br />
[[image:stepper-small.jpg|right]]<br />
<br />
If you need more holding torque, this stepper may be a<br />
good choice.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 12V, 4 phases, 20 ohms resistance, 600 mA current<br />
* holding torque: 0.588 Nm (coils energized)<br />
* detent torque: 0.071 Nm (coils off)<br />
* size: 2.2" motor diameter, 2.0" motor height<br />
* shaft: 1" x 0.25" diameter<br />
* mass: 0.65 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-162026.pdf|data sheet]] (ours is the <br />
57BYG084). There are six leads, three for each independent<br />
coil.<br />
<br />
<br clear=all><br />
<br />
==RC Servo Motors==<br />
<br />
RC servos are convenient for positioning applications that require<br />
significant torque, not much speed, and only moderate positioning<br />
precision. They take three connections, power (+5V, typically),<br />
ground, and a pulsing signal that tells the motor the desired angle (typically a<br />
pulse of 0.5 - 3 ms every 20 ms or so, where the duration of the pulse<br />
indicates the desired angle of the motor).<br />
Inside the motor is a potentiometer that senses the actual angle of<br />
the motor output shaft and a feedback controller that tries to make<br />
the motor angle match that specified by the pulsed signal. There is<br />
also a large gear ratio such that the motor provides high torque at<br />
low speed. Most RC servos have limited angle range, like 180 degrees,<br />
due to the angle-sensing potentiometer.<br />
<br />
<br />
===Futaba S3004 standard ball bearing RC servo motor===<br />
<br />
[[image:RC-servo-small.jpg|right]]<br />
<br />
* motor rotation: 180 degrees<br />
* speed: 60 degrees in 0.23 sec at 4.8V, 0.19 sec at 6V<br />
* torque: 0.31 Nm at 4.8V, 0.4 Nm at 6V<br />
* size: 1.4" height, 0.8" width<br />
* mass: 37.2 g<br />
<br />
These were purchased from Tower Hobbies, part number LM1954.<br />
Higher torque versions are also available.<br />
<br />
<br clear=all><br />
<br />
==Solenoids==<br />
<br />
<br />
<br />
Solenoids are simple on-off actuators consisting of a plunger moving in an<br />
electromagnetic field. If you power the electromagnet, the plunger is<br />
"pushed" or "pulled" a particular stroke length, and if you unpower the<br />
coil, the plunger returns to its original position, usually by a return <br />
spring or gravity. These are simple to control and useful for applications<br />
where the actuator only has to take one of two positions. <br />
<br />
<br />
We stock two solenoids (in addition to many random ones) which are basically<br />
the same, except one is a "pull type" solenoid and the other is a "push type."<br />
<br />
===Jameco 262262 (pull) and 262271 (push) 12V open frame solenoid===<br />
<br />
[[image:solenoids-small.jpg|right]]<br />
<br />
* 12 V, 36 ohm resistance, 333 mA<br />
* holding force: 0.5 N<br />
* stroke: 6 mm<br />
* size: 1.5" length x 1.0" x 0.8" diameter<br />
* shaft diameter: 0.310"<br />
* mass: 96 g<br />
<br />
You can find a data sheet [[Media:jameco-solenoid-262262.pdf|here]].<br />
You can attach a lever (or other mechanical transformer) to the plunger to<br />
get more stroke and less force, or more force and less stroke. If no lever<br />
will meet your specs,<br />
then you will need another solenoid.<br />
<br />
<br />
==AC Motors==<br />
<br />
[[image:ac-servo-small.jpg|right]]<br />
<br />
Some projects need more power than any of the actuators above can<br />
provide. In that case, you may be able to use a Yaskawa AC motor.<br />
These are technically in the Laboratory for Intelligent Mechanical<br />
Systems, but they are available for Mechatronics use. These should<br />
not be a first choice, as (1) they can be dangerous due to their high<br />
power, and (2) they limit the mobility of your project as they must be<br />
plugged into the wall to get 110V AC. You can find information<br />
on these motors and their amplifiers<br />
[http://www.mech.northwestern.edu/courses/433/Writeups/YaskawaMotors/YakawaACservomotors.htm here].</div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:PittmannGM9413J820.jpg&diff=13360File:PittmannGM9413J820.jpg2009-06-09T21:22:37Z<p>MattT: Here is a picture of the Pittman GM9413J820 motor with ruler for scale</p>
<hr />
<div>Here is a picture of the Pittman GM9413J820 motor with ruler for scale</div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:Pittmann700935.jpg&diff=13359File:Pittmann700935.jpg2009-06-09T21:21:41Z<p>MattT: Here is a picture of the Pittman 700935 with a ruler</p>
<hr />
<div>Here is a picture of the Pittman 700935 with a ruler</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Actuators_Available_in_the_Mechatronics_Lab&diff=13303Actuators Available in the Mechatronics Lab2009-06-03T22:38:07Z<p>MattT: /* DC Motors (with gearheads and encoders) */</p>
<hr />
<div>[[image:all-actuators-captions-small.jpg|right]]<br />
<br />
We have acquired a number of actuators that are appropriately sized for<br />
many mechatronics projects. These are the "standard" lab actuators.<br />
You are welcome to borrow them for your project and return them when<br />
you are finished. In addition to the actuators mentioned below, we<br />
have a number of other actuators that we have acquired over the years<br />
that you are welcome to borrow.<br />
<br />
For your particular project, it may be best to spec out and buy a<br />
particular type and size of actuator. If your specifications are not<br />
too critical, however, the actuators below will allow you to get<br />
started right away.<br />
<br />
<br />
__TOC__<br />
<br />
<br />
<br clear=all><br />
<br />
<br />
<br />
==DC Motors (with gearheads and encoders)==<br />
<br />
There are many types of DC motors, but our favorites are brushed<br />
permanent magnet DC motors for their power, price, ubiquity, and<br />
simplicity. Simply put a voltage across the two motor terminals, and<br />
the motor spins. (You can learn about the [[Brushed DC Motor Theory| theory]] of how a brushed DC <br />
motor works and suggested methods<br />
for driving a DC motor elsewhere on this wiki.) <br />
<br />
One problem is that most DC motors tend to rotate at very high speeds,<br />
typically several thousand RPM or more. This is too fast for most<br />
mechatronics applications. Also, they tend to have too little torque.<br />
Both of these problems can be solved by the use of gears on the output<br />
shaft of the motor. If the motor has an N:1 gearhead on its output<br />
shaft (where N>1, typically), then the output shaft of the gearhead<br />
reduces the speed of the motor by a factor of N and increases the<br />
torque of the motor by a factor of N. (You can learn more<br />
about how [[Gears|gears]] work including other issues<br />
they introduce, such as gearhead efficiency and backlash.)<br />
<br />
Another issue is how to determine how far the motor has rotated. You need<br />
''feedback'' from the motor. There are many ways to do this, using<br />
encoders, potentiometers, and tachometers. The most common way to get angle<br />
feedback is through the use of encoders. An encoder is typically attached<br />
to a motor shaft and produces pulses that encode the shaft rotation angle.<br />
These pulses can be read in by the encoder inputs of the Mechatronics Lab<br />
PC/104 stacks.<br />
<br />
So, perhaps the most versatile kind of actuator is a DC motor with a gearhead and an<br />
encoder. Below are some that we keep in the lab. Sometimes DC motors<br />
with gearheads and encoders can be purchased through surplus outlets at<br />
great prices, for prices less than any of the single components (motor,<br />
gearhead, encoder) could be purchased individually. That's how many<br />
copies of the actuators below were purchased. If you see a great<br />
deal on a nice-sized motor plus gearhead plus encoder, of which many<br />
copies can be purchased, let us know!<br />
<br />
===6W Maxon motor with 6:1 gearhead and 100 line encoder===<br />
<br />
<br />
[[image:maxon-small2.jpg|right]]<br />
<br />
<br />
'''Summary:'''<br />
* 24 V, 41.5 ohms resistance, max current 0.58 Amps<br />
* max torque: 0.15 Nm (approx)<br />
* max speed: 600 RPM (approx)<br />
* encoder: 600 counts/rev at output shaft, 2400 counts/rev in 4x decoding mode<br />
<br />
<br />
<br clear=all><br />
<br />
The motor is rated at 24 volts, giving a no-load (maximum)<br />
speed of 3990 RPM (about 418 radians/sec) and a (maximum) stall torque of 31.9 mNm (milli<br />
Newton meters). The terminal resistance (the resistance through the<br />
motor windings) is 41.5 ohms. This means if you put 24 V across it,<br />
the maximum current that it will draw is 24/41.5 = 0.58 Amps. This<br />
maximum current occurs when the motor is stalled and generating its<br />
maximum torque. Motor torque is proportional to the motor current by<br />
the constant of proportionality called the ''torque constant'',<br />
which is different for every motor.<br />
<br />
The motor is called a 6 Watt motor because that is the maximum<br />
electrical power (current times voltage) that can be put into the<br />
motor on a continuous basis. Beyond this power level, the amount of<br />
power dissipated by the resistance of the motor windings will cause<br />
the windings to heat up unacceptably. (It is fine to overpower the<br />
motor intermittently, allowing the coils to cool so that the average<br />
power does not exceed the rated power.) At this operating point, <br />
the motor draws 244 mA, giving 24 V x 0.244 A = 5.86 W electrical input<br />
power. At this operating point, the speed of the motor is approximately<br />
1689 RPM, or 177 radians/sec, and the torque of the motor is 13.5 mNm,<br />
giving 177 rad/sec x 0.0135 Nm = 2.39 W of mechanical output power,<br />
giving a power-conversion efficiency of about 41% at this operating point.<br />
The maximum efficiency of the motor is 70%, which occurs at a higher<br />
speed and lower torque. The maximum mechanical power you can get out<br />
of the motor is (1/2 max torque) x (1/2 max speed) = 3.33 W. This is<br />
beyond the continuous operation recommendation, but it is fine to<br />
run it for short periods at this operating point.<br />
<br />
Often you will want to run the motor at lower voltages, for instance<br />
at 12 V, instead of the rated 24 V. In this case just multiply the<br />
max current, speed, and torques by the factor 12/24 = 1/2. In particular,<br />
the maximum output power will be only (1/2) x (1/2) = 1/4 the maximum at 24 V.<br />
<br />
This actuator comes with a 6:1 spur gearhead, which increases the<br />
torque available at the gearhead's output shaft by a factor of 6 and<br />
decreases the speed by a factor of 6. (In this ideal case, the<br />
power at the gearhead's output shaft is equal to the power at the input.<br />
In practice, gearheads have an efficiency also; the maximum<br />
efficiency of the gearhead here is 81%. This reduces the torque<br />
available.)<br />
<br />
In summary, then, if your application requires no more than about 6 x<br />
31.9 mNm = 0.19 Nm maximum torque, 3990 RPM / 6 = 665 RPM max speed,<br />
and 3.3 W max mechanical power, this may be the motor for you.<br />
Reduce those values by a factor of 1/2, 1/2, and 1/4, respectively, if<br />
you are operating the motor with 12 V max instead of 24 V max.<br />
<br />
This actuator also comes with a 100 line single-ended incremental optical encoder,<br />
with outputs A+ and B+. There is no index channel. The encoder is<br />
attached to the motor. Each of the A+ and B+ channels makes 100 pulses<br />
per revolution of the motor, or 6 x 100 = 600 pulses per revolution of<br />
the output shaft of the gearhead. This means the encoder provides<br />
360 deg / 600 pulses = 0.6 deg/pulse resolution when the pulses are <br />
decoded with the 1x scheme, or 0.15 deg/pulse resolution with the 4x<br />
decoding scheme.<br />
<br />
Information about the Maxon motor is given in this [[Media:maxon-2140-specs.pdf|data sheet]] which includes <br />
other motors in this family (ours is the 24V version)<br />
and this [[Media:maxon-our-specific-motor.pdf|data sheet]] which gives only<br />
the information on this motor. Information on the 6:1 gearhead can be found <br />
[[Media:maxon-gearhead.pdf|here]]. The encoder pin-out is indicated below:<br />
<br />
<br clear=all><br />
<br />
[[image:encoder-maxon.jpg|right]]<br />
<br />
<br clear=all><br />
<br />
The encoder comes with a 4-connector ribbon cable, corresponding to GND, Channel A, Vcc (usually +5V), and Channel B, as<br />
shown on the left. Here the ribbon cable is broken out into a 10-pin connector (which we have in the lab). The connector<br />
above is made to work with the PC/104 stacks, and the pin-out is shown. Always make sure you have the right connections<br />
for your encoder so you don't damage it!<br />
<br />
<br clear=all><br />
<br />
===Pittman GM8224 motor with 19.5:1 gearhead and 500 line encoder===<br />
<br />
[[image:pittman-small.jpg|right]]<br />
<br />
If you need more power than the motor above, this gearmotor may be a good choice.<br />
As an added bonus, it provides much higher encoder resolution.<br />
<br />
'''Summary:'''<br />
* 24 V, 4.33 ohms resistance, max current 5.54 Amps<br />
* max torque: 2 Nm (approx)<br />
* max speed: 500 RPM (approx)<br />
* encoder: 9750 counts/rev at output shaft, 39,000 counts/rev in 4x decoding mode<br />
<br />
<br clear=all><br />
<br />
This motor is also rated at 24 V, with a terminal resistance of 4.33 ohms,<br />
giving a stall (maximum) current of 5.54 Amps. The stall torque of the motor<br />
itself is 0.1186 Nm<br />
and the no-load (maximum) speed is 10,158 RPM (1064 radians/sec). The<br />
recommended maximum continuous torque is 0.0185 Nm which occurs at <br />
8573 RPM (898 radians/sec). Taken together, the maximum motor mechanical power<br />
is (1/2 Tmax) x (1/2 nmax) = 31.5 W and the maximum recommended continuous<br />
mechanical power is 16.6 W. The maximum electrical input power occurs when<br />
the motor is stalled (or starting) and is 24 V x 5.54 A = 133 W. If you<br />
operate the motor at a smaller voltage V2, then multiply the currents, speeds,<br />
and torques above by a factor V2/24 and the power by a factor of (V2/24)^2.<br />
<br />
This motor has a 19.5:1 gearhead with a power conversion efficiency of 73%. <br />
Ignoring the efficiency for the moment, the 19.5:1 gearbox means that this<br />
actuator may be appropriate if our application calls for no more than a <br />
maximum speed of 10,158 RPM / 19.5 = 521 RPM and a maximum torque of<br />
0.1186 Nm x 19.5 = 2.3 Nm. In other words, the output shaft speed is similar<br />
to the Maxon gearmotor above, but with about 10 times the torque. <br />
<br />
This motor comes with a 500 line encoder attached to the motor shaft. The<br />
encoder has output channels A+ and B+ (no index pulse). This means that<br />
the encoder provides 500 x 19.5 = 9750 pulses per revolution of the output shaft.<br />
In the 4x decoding mode, this gives 39,000 counts per revolution, or a resolution<br />
of 360/39,000 = 0.00923 degrees.<br />
<br />
We also have a limited number of Pittman GM8712 motors with a 19.5:1 gearhead<br />
and 512 line encoder. These motors are also rated at 24V but have a higher<br />
terminal resistance of 12.1 ohms, giving a maximum current of 24/12.1 = 1.99 Amps.<br />
They have a maximum speed of 7847 RPM and maximum torque of 0.052 Nm before the<br />
gearhead, or (ignoring gearhead efficiency) 402 RPM and 1.01 Nm after the<br />
gearhead. This motor is less powerful and draws less current, which may<br />
be appropriate for some applications.<br />
The encoder provides 9984 pulses per revolution of the output shaft<br />
of the gearhead, or 360/(4 x 9984) = 0.009 degrees resolution in 4x decoding mode.<br />
<br />
See the [[Media:pittmangearmotor.pdf|data sheet]] for more detailed<br />
information on these Pittman 8224 and 8712 gearmotors. The 8712 is not treated<br />
explicitly, but is believed to be similar to the 8722.<br />
<br />
The quadrature encoder has four wires: black (GND), red (+5V), and blue and yellow as <br />
channels A and B.<br />
<br />
===Pittman 700935 motor with 500 line encoder===<br />
<br />
[[image:Pittmann700935.jpg|right]]<br />
<br />
* Speed: 5000 RPM<br />
* Voltage: 24 V<br />
* Torque: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 2000 CPR in 4X mode at output shaft<br />
* Gearhead: N/A<br />
* Weight: unknown<br />
* Length: unknown<br />
* Motor Constant: unknown<br />
<br />
<br />
===Pittman GM9413J820 motor with 500 line encoder===<br />
<br />
[[image:PittmannGM9413J820.jpg|right]]<br />
<br />
* Speed: 85 RPM<br />
* Voltage: 24 V<br />
* Torque: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 39,400 CPR in 4X mode at output shaft<br />
* Gearhead: 19.7:1<br />
* Weight: unknown<br />
* Length: unknown<br />
* Motor Constant: unknown<br />
<br />
===Faulhaber 1524E006S motor with 141:1 gearhead and HES164A magnetic quadrature encoder===<br />
<br />
[[image:faulhaber.png|right]]<br />
<br />
'''Summary:'''<br />
* motor rated at 6V, 12 ohms resistance (motor: 1524E006S123, where 123 is a special order)<br />
* 141:1 gearhead (gearhead: 15/5S141:1K832)<br />
* max speed at 6V: approximately 80 RPM at gearhead output<br />
* quadrature encoder with 1 line per motor revolution, or 141 x 4 = 564 counts/rev at output shaft in 4x decoding mode (encoder: HES164A)<br />
<br clear=all><br />
<br />
This little motor is the right size, speed, and torque for small wheeled mobile robots.<br />
Ours were bought surplus from [http://www.bgmicro.com bgmicro.com]. This <br />
[http://www.robotroom.com/FaulhaberGearmotor.html page] by<br />
David Cook has a lot of great information on this motor + gearhead + encoder combination.<br />
More info can be found in this [[Media:faulhaber-datasheet.pdf|data sheet]] from Faulhaber,<br />
though our exact model encoder and motor are not listed. The gearhead has a right-angle<br />
drive at the output.<br />
<br />
<br clear=all><br />
<br />
[[image:faulhaber-pinout.jpg|right]]<br />
<br />
The pins on the connector are (see figure at right):<br />
<br />
<br />
1. Motor + <br><br />
2. +5V (or similar) to power the encoder<br><br />
3. Encoder channel A<br><br />
4. Encoder channel B<br><br />
5. GND for the encoder<br><br />
6. Motor -<br />
<br />
<br />
Encoder channels A and B can sink (connect to ground) up to probably 25mA like most Hall sensors. There is only a a weak pull-up resistor inside, perhaps 10K, so they can only source (connect to +5) about 2mA. If you find the logic high signal from the encoder channel is not close enough to +5, which can happen even due to loading by an LED, you may want to add an external pull-up resistor from each encoder channel to +5. 470ohms is a good choice.<br />
<br />
<br clear=all><br />
<br />
[[image:faulhaber-wheel.jpg|right]]<br />
<br />
These [http://www.solarbotics.com/products/gmpw/ wheels] can be used with the motor (with the<br />
right-angle drive) if you drill out the center of the wheel with a 9/32" bit (approximately). Then you<br />
should get a nice tight press-fit. We have some of these wheels in the lab. This press-fit is not <br />
suitable for high-torque applications, though; the shaft may begin to slip.<br />
<br />
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<br />
===Globe motor with 187.68:1 gearhead and 500 line encoder===<br />
<br />
[[image:globe-motor.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* motor rated at 12V, 21 ohms resistance (0.57 A stall current)<br />
* 187.68:1 gearhead for high torque and low speed<br />
* max speed at 12V: approximately 17 RPM at gearhead output (no load speed, motor alone: approx 3000 RPM)<br />
* torque constant (motor alone): approximately 34 mNm/A (or 3.6 mV/RPM)<br />
* stall torque: motor alone: 0.019 Nm; with gearhead 2.4 Nm (based on torque multiplier of 125, less than the 187 gear ratio due to efficiency losses)<br />
* quadrature encoder with 500 lines per motor revolution, or 500 x 4 x 187.68 = 375,360 counts/rev at output shaft in 4x decoding mode (encoder: HEDS-5505 A04)<br />
<br clear=all><br />
<br />
This small motor combines with a high resolution encoder and a high gear ratio gearbox to give a high torque, low speed actuator with high resolution position sensing (and velocity sensing by finite differencing). The stall torque for this gearmotor (at 12 V) is approximately the same as that for the Pittman GM8224 gearmotor (at 24 V), but the max speed for the PIttman gearmotor is 20 times higher. The pin-out for the encoder is shown below. You can attach to the encoder using a Samtec IDSS-05-D-12.00 cable (shown in the middle below; order directly from [http://www.samtec.com Samtec], about $3.50 each and we have several in the lab), a less-expensive 5-pin cable CAB2154 from [https://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=12868 bgmicro] (we have several in the lab), or you can make your own cable using stranded wires (22 AWG or ribbon cable) crimped or soldered in female Molex terminal pins (Molex series KK 2759, part number WM1114CT-ND on digikey) in a Molex 5 position connector housing (Molex series KK 2695, part number WM1578-ND on digikey), shown at right below. (See [[Making a Molex Connector]] for more details.) The [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder recommends putting a 3.2k pull-up resistor on Channels A and B (i.e., 3.2k resistors from these lines to +5V). The encoder works without these, but the datasheet indicates that you get better rise times on the encoder signals at high speeds when the pull-up resistors are added.<br />
<br />
[[image:globe-encoder-annotated.jpg|300px]]<br />
[[image:globe-encoder-cable.jpg|200px]]<br />
[[image:globe-encoder-cable-molex.jpg|200px]]<br />
<br />
If you want a higher-speed (up to 3000 RPM at 12V) lower-torque actuator, you can try removing the gearbox. This task takes a bit of work and may require a bit of machining. See [[Accessing_Pinion_of_Globe_Motor|here]]. This page also shows how to remove the encoder, in case you want to use it in a project without the motor.<br />
<br />
The two motor power leads are wound through a ferrite toroid to suppress EMI "noise."<br />
<br />
Here you can find a [[Media:globe-cad.pdf|cad file]] describing this actuator, a [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder, and a [[Media:idss-connector.pdf|datasheet]] for the Samtec IDSS-05-D-12.00 connector.<br />
<br />
<br clear=all><br />
<br />
===GM3 and GM9 Gearmotors===<br />
<br />
[[image:GM3.png|right]]<br />
<br />
'''Summary:''' (GM3 pictured at right)<br />
* rated at 6V, approx 10 ohms resistance<br />
* 224:1 gearhead (GM3) or 143:1 gearhead (GM9)<br />
* max speed at 6V approximately 43 RPM (GM3) or 84 RPM (GM9)<br />
* stall torque at 6V approximately 73 oz-in (GM3) or 52 oz-in (GM9)<br />
* no encoder installed, but can be modified to add one; see [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|here]]<br />
* size: 70 x 22.5 x 37 mm<br />
<br clear=all><br />
<br />
These highly-geared motors can be bought new at [http://www.solarbotics.com solarbotics.com] or [http://www.hobbyengineering.com hobbyengineering.com]. These motors work with these [http://www.solarbotics.com/products/gmpw/ wheels], which we have in<br />
the lab. The motors do not come with encoders, but you can [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|add one yourself]],<br />
similar to the magnetic encoder on the Faulhaber motor above.<br />
<br />
<br clear=all><br />
<br />
==Stepper Motors==<br />
<br />
Stepper motors move in discrete steps. The controller energizes electromagnet<br />
coils, and the motor's rotor rotates to the nearest equilibrium point. By<br />
proper sequencing of which coils are energized, the motor rotates as desired<br />
(and, if the rotation is fast enough, may simply pass through the equilibrium<br />
points without stopping). <br />
<br />
One nice thing about stepper motors is that they do not require<br />
feedback; we know how far the motor has rotated, because we commanded<br />
the motion. This becomes a problem if we try to rotate the motor too<br />
fast, or if the load is larger than expected --- the motor may not<br />
actually do what we commanded. Stepper motors are a <br />
good choice for relatively low-torque applications where the loads<br />
are consistent, so we can be assured our commanded motions are followed.<br />
<br />
===Jameco 163395 8.4V bipolar stepper motor===<br />
<br />
[[image:small-stepper.jpg|right]]<br />
<br />
Although this motor is rated at 8.4V, it is possible<br />
to run it at lower or slightly higher voltages.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 8.4V, 2 phases, 30 ohms resistance, 280 mA current<br />
* holding torque: 0.081 Nm (coils energized)<br />
* detent torque: 0.0037 Nm (coils off)<br />
* size: 1.64" motor diameter, 1.2" motor height<br />
* shaft: 0.29" x 0.155" diameter<br />
* mass: 0.24 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-163395.pdf|data sheet]].<br />
There are four leads, two for each independent coil.<br />
<br />
<br clear=all><br />
<br />
===Jameco 162026CX 12V unipolar stepper motor===<br />
<br />
[[image:stepper-small.jpg|right]]<br />
<br />
If you need more holding torque, this stepper may be a<br />
good choice.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 12V, 4 phases, 20 ohms resistance, 600 mA current<br />
* holding torque: 0.588 Nm (coils energized)<br />
* detent torque: 0.071 Nm (coils off)<br />
* size: 2.2" motor diameter, 2.0" motor height<br />
* shaft: 1" x 0.25" diameter<br />
* mass: 0.65 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-162026.pdf|data sheet]] (ours is the <br />
57BYG084). There are six leads, three for each independent<br />
coil.<br />
<br />
<br clear=all><br />
<br />
==RC Servo Motors==<br />
<br />
RC servos are convenient for positioning applications that require<br />
significant torque, not much speed, and only moderate positioning<br />
precision. They take three connections, power (+5V, typically),<br />
ground, and a pulsing signal that tells the motor the desired angle (typically a<br />
pulse of 0.5 - 3 ms every 20 ms or so, where the duration of the pulse<br />
indicates the desired angle of the motor).<br />
Inside the motor is a potentiometer that senses the actual angle of<br />
the motor output shaft and a feedback controller that tries to make<br />
the motor angle match that specified by the pulsed signal. There is<br />
also a large gear ratio such that the motor provides high torque at<br />
low speed. Most RC servos have limited angle range, like 180 degrees,<br />
due to the angle-sensing potentiometer.<br />
<br />
<br />
===Futaba S3004 standard ball bearing RC servo motor===<br />
<br />
[[image:RC-servo-small.jpg|right]]<br />
<br />
* motor rotation: 180 degrees<br />
* speed: 60 degrees in 0.23 sec at 4.8V, 0.19 sec at 6V<br />
* torque: 0.31 Nm at 4.8V, 0.4 Nm at 6V<br />
* size: 1.4" height, 0.8" width<br />
* mass: 37.2 g<br />
<br />
These were purchased from Tower Hobbies, part number LM1954.<br />
Higher torque versions are also available.<br />
<br />
<br clear=all><br />
<br />
==Solenoids==<br />
<br />
<br />
<br />
Solenoids are simple on-off actuators consisting of a plunger moving in an<br />
electromagnetic field. If you power the electromagnet, the plunger is<br />
"pushed" or "pulled" a particular stroke length, and if you unpower the<br />
coil, the plunger returns to its original position, usually by a return <br />
spring or gravity. These are simple to control and useful for applications<br />
where the actuator only has to take one of two positions. <br />
<br />
<br />
We stock two solenoids (in addition to many random ones) which are basically<br />
the same, except one is a "pull type" solenoid and the other is a "push type."<br />
<br />
===Jameco 262262 (pull) and 262271 (push) 12V open frame solenoid===<br />
<br />
[[image:solenoids-small.jpg|right]]<br />
<br />
* 12 V, 36 ohm resistance, 333 mA<br />
* holding force: 0.5 N<br />
* stroke: 6 mm<br />
* size: 1.5" length x 1.0" x 0.8" diameter<br />
* shaft diameter: 0.310"<br />
* mass: 96 g<br />
<br />
You can find a data sheet [[Media:jameco-solenoid-262262.pdf|here]].<br />
You can attach a lever (or other mechanical transformer) to the plunger to<br />
get more stroke and less force, or more force and less stroke. If no lever<br />
will meet your specs,<br />
then you will need another solenoid.<br />
<br />
<br />
==AC Motors==<br />
<br />
[[image:ac-servo-small.jpg|right]]<br />
<br />
Some projects need more power than any of the actuators above can<br />
provide. In that case, you may be able to use a Yaskawa AC motor.<br />
These are technically in the Laboratory for Intelligent Mechanical<br />
Systems, but they are available for Mechatronics use. These should<br />
not be a first choice, as (1) they can be dangerous due to their high<br />
power, and (2) they limit the mobility of your project as they must be<br />
plugged into the wall to get 110V AC. You can find information<br />
on these motors and their amplifiers<br />
[http://www.mech.northwestern.edu/courses/433/Writeups/YaskawaMotors/YakawaACservomotors.htm here].</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Actuators_Available_in_the_Mechatronics_Lab&diff=13302Actuators Available in the Mechatronics Lab2009-06-03T22:34:34Z<p>MattT: /* DC Motors (with gearheads and encoders) */</p>
<hr />
<div>[[image:all-actuators-captions-small.jpg|right]]<br />
<br />
We have acquired a number of actuators that are appropriately sized for<br />
many mechatronics projects. These are the "standard" lab actuators.<br />
You are welcome to borrow them for your project and return them when<br />
you are finished. In addition to the actuators mentioned below, we<br />
have a number of other actuators that we have acquired over the years<br />
that you are welcome to borrow.<br />
<br />
For your particular project, it may be best to spec out and buy a<br />
particular type and size of actuator. If your specifications are not<br />
too critical, however, the actuators below will allow you to get<br />
started right away.<br />
<br />
<br />
__TOC__<br />
<br />
<br />
<br clear=all><br />
<br />
<br />
<br />
==DC Motors (with gearheads and encoders)==<br />
<br />
There are many types of DC motors, but our favorites are brushed<br />
permanent magnet DC motors for their power, price, ubiquity, and<br />
simplicity. Simply put a voltage across the two motor terminals, and<br />
the motor spins. (You can learn about the [[Brushed DC Motor Theory| theory]] of how a brushed DC <br />
motor works and suggested methods<br />
for driving a DC motor elsewhere on this wiki.) <br />
<br />
One problem is that most DC motors tend to rotate at very high speeds,<br />
typically several thousand RPM or more. This is too fast for most<br />
mechatronics applications. Also, they tend to have too little torque.<br />
Both of these problems can be solved by the use of gears on the output<br />
shaft of the motor. If the motor has an N:1 gearhead on its output<br />
shaft (where N>1, typically), then the output shaft of the gearhead<br />
reduces the speed of the motor by a factor of N and increases the<br />
torque of the motor by a factor of N. (You can learn more<br />
about how [[Gears|gears]] work including other issues<br />
they introduce, such as gearhead efficiency and backlash.)<br />
<br />
Another issue is how to determine how far the motor has rotated. You need<br />
''feedback'' from the motor. There are many ways to do this, using<br />
encoders, potentiometers, and tachometers. The most common way to get angle<br />
feedback is through the use of encoders. An encoder is typically attached<br />
to a motor shaft and produces pulses that encode the shaft rotation angle.<br />
These pulses can be read in by the encoder inputs of the Mechatronics Lab<br />
PC/104 stacks.<br />
<br />
So, perhaps the most versatile kind of actuator is a DC motor with a gearhead and an<br />
encoder. Below are some that we keep in the lab. Sometimes DC motors<br />
with gearheads and encoders can be purchased through surplus outlets at<br />
great prices, for prices less than any of the single components (motor,<br />
gearhead, encoder) could be purchased individually. That's how many<br />
copies of the actuators below were purchased. If you see a great<br />
deal on a nice-sized motor plus gearhead plus encoder, of which many<br />
copies can be purchased, let us know!<br />
<br />
===6W Maxon motor with 6:1 gearhead and 100 line encoder===<br />
<br />
<br />
[[image:maxon-small2.jpg|right]]<br />
<br />
<br />
'''Summary:'''<br />
* 24 V, 41.5 ohms resistance, max current 0.58 Amps<br />
* max torque: 0.15 Nm (approx)<br />
* max speed: 600 RPM (approx)<br />
* encoder: 600 counts/rev at output shaft, 2400 counts/rev in 4x decoding mode<br />
<br />
<br />
<br clear=all><br />
<br />
The motor is rated at 24 volts, giving a no-load (maximum)<br />
speed of 3990 RPM (about 418 radians/sec) and a (maximum) stall torque of 31.9 mNm (milli<br />
Newton meters). The terminal resistance (the resistance through the<br />
motor windings) is 41.5 ohms. This means if you put 24 V across it,<br />
the maximum current that it will draw is 24/41.5 = 0.58 Amps. This<br />
maximum current occurs when the motor is stalled and generating its<br />
maximum torque. Motor torque is proportional to the motor current by<br />
the constant of proportionality called the ''torque constant'',<br />
which is different for every motor.<br />
<br />
The motor is called a 6 Watt motor because that is the maximum<br />
electrical power (current times voltage) that can be put into the<br />
motor on a continuous basis. Beyond this power level, the amount of<br />
power dissipated by the resistance of the motor windings will cause<br />
the windings to heat up unacceptably. (It is fine to overpower the<br />
motor intermittently, allowing the coils to cool so that the average<br />
power does not exceed the rated power.) At this operating point, <br />
the motor draws 244 mA, giving 24 V x 0.244 A = 5.86 W electrical input<br />
power. At this operating point, the speed of the motor is approximately<br />
1689 RPM, or 177 radians/sec, and the torque of the motor is 13.5 mNm,<br />
giving 177 rad/sec x 0.0135 Nm = 2.39 W of mechanical output power,<br />
giving a power-conversion efficiency of about 41% at this operating point.<br />
The maximum efficiency of the motor is 70%, which occurs at a higher<br />
speed and lower torque. The maximum mechanical power you can get out<br />
of the motor is (1/2 max torque) x (1/2 max speed) = 3.33 W. This is<br />
beyond the continuous operation recommendation, but it is fine to<br />
run it for short periods at this operating point.<br />
<br />
Often you will want to run the motor at lower voltages, for instance<br />
at 12 V, instead of the rated 24 V. In this case just multiply the<br />
max current, speed, and torques by the factor 12/24 = 1/2. In particular,<br />
the maximum output power will be only (1/2) x (1/2) = 1/4 the maximum at 24 V.<br />
<br />
This actuator comes with a 6:1 spur gearhead, which increases the<br />
torque available at the gearhead's output shaft by a factor of 6 and<br />
decreases the speed by a factor of 6. (In this ideal case, the<br />
power at the gearhead's output shaft is equal to the power at the input.<br />
In practice, gearheads have an efficiency also; the maximum<br />
efficiency of the gearhead here is 81%. This reduces the torque<br />
available.)<br />
<br />
In summary, then, if your application requires no more than about 6 x<br />
31.9 mNm = 0.19 Nm maximum torque, 3990 RPM / 6 = 665 RPM max speed,<br />
and 3.3 W max mechanical power, this may be the motor for you.<br />
Reduce those values by a factor of 1/2, 1/2, and 1/4, respectively, if<br />
you are operating the motor with 12 V max instead of 24 V max.<br />
<br />
This actuator also comes with a 100 line single-ended incremental optical encoder,<br />
with outputs A+ and B+. There is no index channel. The encoder is<br />
attached to the motor. Each of the A+ and B+ channels makes 100 pulses<br />
per revolution of the motor, or 6 x 100 = 600 pulses per revolution of<br />
the output shaft of the gearhead. This means the encoder provides<br />
360 deg / 600 pulses = 0.6 deg/pulse resolution when the pulses are <br />
decoded with the 1x scheme, or 0.15 deg/pulse resolution with the 4x<br />
decoding scheme.<br />
<br />
Information about the Maxon motor is given in this [[Media:maxon-2140-specs.pdf|data sheet]] which includes <br />
other motors in this family (ours is the 24V version)<br />
and this [[Media:maxon-our-specific-motor.pdf|data sheet]] which gives only<br />
the information on this motor. Information on the 6:1 gearhead can be found <br />
[[Media:maxon-gearhead.pdf|here]]. The encoder pin-out is indicated below:<br />
<br />
<br clear=all><br />
<br />
[[image:encoder-maxon.jpg|right]]<br />
<br />
<br clear=all><br />
<br />
The encoder comes with a 4-connector ribbon cable, corresponding to GND, Channel A, Vcc (usually +5V), and Channel B, as<br />
shown on the left. Here the ribbon cable is broken out into a 10-pin connector (which we have in the lab). The connector<br />
above is made to work with the PC/104 stacks, and the pin-out is shown. Always make sure you have the right connections<br />
for your encoder so you don't damage it!<br />
<br />
<br clear=all><br />
<br />
===Pittman GM8224 motor with 19.5:1 gearhead and 500 line encoder===<br />
<br />
[[image:pittman-small.jpg|right]]<br />
<br />
If you need more power than the motor above, this gearmotor may be a good choice.<br />
As an added bonus, it provides much higher encoder resolution.<br />
<br />
'''Summary:'''<br />
* 24 V, 4.33 ohms resistance, max current 5.54 Amps<br />
* max torque: 2 Nm (approx)<br />
* max speed: 500 RPM (approx)<br />
* encoder: 9750 counts/rev at output shaft, 39,000 counts/rev in 4x decoding mode<br />
<br />
<br clear=all><br />
<br />
This motor is also rated at 24 V, with a terminal resistance of 4.33 ohms,<br />
giving a stall (maximum) current of 5.54 Amps. The stall torque of the motor<br />
itself is 0.1186 Nm<br />
and the no-load (maximum) speed is 10,158 RPM (1064 radians/sec). The<br />
recommended maximum continuous torque is 0.0185 Nm which occurs at <br />
8573 RPM (898 radians/sec). Taken together, the maximum motor mechanical power<br />
is (1/2 Tmax) x (1/2 nmax) = 31.5 W and the maximum recommended continuous<br />
mechanical power is 16.6 W. The maximum electrical input power occurs when<br />
the motor is stalled (or starting) and is 24 V x 5.54 A = 133 W. If you<br />
operate the motor at a smaller voltage V2, then multiply the currents, speeds,<br />
and torques above by a factor V2/24 and the power by a factor of (V2/24)^2.<br />
<br />
This motor has a 19.5:1 gearhead with a power conversion efficiency of 73%. <br />
Ignoring the efficiency for the moment, the 19.5:1 gearbox means that this<br />
actuator may be appropriate if our application calls for no more than a <br />
maximum speed of 10,158 RPM / 19.5 = 521 RPM and a maximum torque of<br />
0.1186 Nm x 19.5 = 2.3 Nm. In other words, the output shaft speed is similar<br />
to the Maxon gearmotor above, but with about 10 times the torque. <br />
<br />
This motor comes with a 500 line encoder attached to the motor shaft. The<br />
encoder has output channels A+ and B+ (no index pulse). This means that<br />
the encoder provides 500 x 19.5 = 9750 pulses per revolution of the output shaft.<br />
In the 4x decoding mode, this gives 39,000 counts per revolution, or a resolution<br />
of 360/39,000 = 0.00923 degrees.<br />
<br />
We also have a limited number of Pittman GM8712 motors with a 19.5:1 gearhead<br />
and 512 line encoder. These motors are also rated at 24V but have a higher<br />
terminal resistance of 12.1 ohms, giving a maximum current of 24/12.1 = 1.99 Amps.<br />
They have a maximum speed of 7847 RPM and maximum torque of 0.052 Nm before the<br />
gearhead, or (ignoring gearhead efficiency) 402 RPM and 1.01 Nm after the<br />
gearhead. This motor is less powerful and draws less current, which may<br />
be appropriate for some applications.<br />
The encoder provides 9984 pulses per revolution of the output shaft<br />
of the gearhead, or 360/(4 x 9984) = 0.009 degrees resolution in 4x decoding mode.<br />
<br />
See the [[Media:pittmangearmotor.pdf|data sheet]] for more detailed<br />
information on these Pittman 8224 and 8712 gearmotors. The 8712 is not treated<br />
explicitly, but is believed to be similar to the 8722.<br />
<br />
The quadrature encoder has four wires: black (GND), red (+5V), and blue and yellow as <br />
channels A and B.<br />
<br />
===Pittman 700935 motor with 500 line encoder===<br />
<br />
[[image:Pittmann700.jpg|right]]<br />
<br />
* Speed: 5000 RPM<br />
* Voltage: 24 V<br />
* Torque: unknown<br />
* Encoder: 500 CPR 2 channel encoder, 2000 CPR in 4X mode at output shaft<br />
* Gearhead: N/A<br />
* Weight: unknown<br />
* Length: unknown<br />
* Motor Constant: unknown<br />
<br />
===Faulhaber 1524E006S motor with 141:1 gearhead and HES164A magnetic quadrature encoder===<br />
<br />
[[image:faulhaber.png|right]]<br />
<br />
'''Summary:'''<br />
* motor rated at 6V, 12 ohms resistance (motor: 1524E006S123, where 123 is a special order)<br />
* 141:1 gearhead (gearhead: 15/5S141:1K832)<br />
* max speed at 6V: approximately 80 RPM at gearhead output<br />
* quadrature encoder with 1 line per motor revolution, or 141 x 4 = 564 counts/rev at output shaft in 4x decoding mode (encoder: HES164A)<br />
<br clear=all><br />
<br />
This little motor is the right size, speed, and torque for small wheeled mobile robots.<br />
Ours were bought surplus from [http://www.bgmicro.com bgmicro.com]. This <br />
[http://www.robotroom.com/FaulhaberGearmotor.html page] by<br />
David Cook has a lot of great information on this motor + gearhead + encoder combination.<br />
More info can be found in this [[Media:faulhaber-datasheet.pdf|data sheet]] from Faulhaber,<br />
though our exact model encoder and motor are not listed. The gearhead has a right-angle<br />
drive at the output.<br />
<br />
<br clear=all><br />
<br />
[[image:faulhaber-pinout.jpg|right]]<br />
<br />
The pins on the connector are (see figure at right):<br />
<br />
<br />
1. Motor + <br><br />
2. +5V (or similar) to power the encoder<br><br />
3. Encoder channel A<br><br />
4. Encoder channel B<br><br />
5. GND for the encoder<br><br />
6. Motor -<br />
<br />
<br />
Encoder channels A and B can sink (connect to ground) up to probably 25mA like most Hall sensors. There is only a a weak pull-up resistor inside, perhaps 10K, so they can only source (connect to +5) about 2mA. If you find the logic high signal from the encoder channel is not close enough to +5, which can happen even due to loading by an LED, you may want to add an external pull-up resistor from each encoder channel to +5. 470ohms is a good choice.<br />
<br />
<br clear=all><br />
<br />
[[image:faulhaber-wheel.jpg|right]]<br />
<br />
These [http://www.solarbotics.com/products/gmpw/ wheels] can be used with the motor (with the<br />
right-angle drive) if you drill out the center of the wheel with a 9/32" bit (approximately). Then you<br />
should get a nice tight press-fit. We have some of these wheels in the lab. This press-fit is not <br />
suitable for high-torque applications, though; the shaft may begin to slip.<br />
<br />
<br clear=all><br />
<br />
===Globe motor with 187.68:1 gearhead and 500 line encoder===<br />
<br />
[[image:globe-motor.jpg|right|400px]]<br />
<br />
'''Summary:'''<br />
* motor rated at 12V, 21 ohms resistance (0.57 A stall current)<br />
* 187.68:1 gearhead for high torque and low speed<br />
* max speed at 12V: approximately 17 RPM at gearhead output (no load speed, motor alone: approx 3000 RPM)<br />
* torque constant (motor alone): approximately 34 mNm/A (or 3.6 mV/RPM)<br />
* stall torque: motor alone: 0.019 Nm; with gearhead 2.4 Nm (based on torque multiplier of 125, less than the 187 gear ratio due to efficiency losses)<br />
* quadrature encoder with 500 lines per motor revolution, or 500 x 4 x 187.68 = 375,360 counts/rev at output shaft in 4x decoding mode (encoder: HEDS-5505 A04)<br />
<br clear=all><br />
<br />
This small motor combines with a high resolution encoder and a high gear ratio gearbox to give a high torque, low speed actuator with high resolution position sensing (and velocity sensing by finite differencing). The stall torque for this gearmotor (at 12 V) is approximately the same as that for the Pittman GM8224 gearmotor (at 24 V), but the max speed for the PIttman gearmotor is 20 times higher. The pin-out for the encoder is shown below. You can attach to the encoder using a Samtec IDSS-05-D-12.00 cable (shown in the middle below; order directly from [http://www.samtec.com Samtec], about $3.50 each and we have several in the lab), a less-expensive 5-pin cable CAB2154 from [https://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=12868 bgmicro] (we have several in the lab), or you can make your own cable using stranded wires (22 AWG or ribbon cable) crimped or soldered in female Molex terminal pins (Molex series KK 2759, part number WM1114CT-ND on digikey) in a Molex 5 position connector housing (Molex series KK 2695, part number WM1578-ND on digikey), shown at right below. (See [[Making a Molex Connector]] for more details.) The [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder recommends putting a 3.2k pull-up resistor on Channels A and B (i.e., 3.2k resistors from these lines to +5V). The encoder works without these, but the datasheet indicates that you get better rise times on the encoder signals at high speeds when the pull-up resistors are added.<br />
<br />
[[image:globe-encoder-annotated.jpg|300px]]<br />
[[image:globe-encoder-cable.jpg|200px]]<br />
[[image:globe-encoder-cable-molex.jpg|200px]]<br />
<br />
If you want a higher-speed (up to 3000 RPM at 12V) lower-torque actuator, you can try removing the gearbox. This task takes a bit of work and may require a bit of machining. See [[Accessing_Pinion_of_Globe_Motor|here]]. This page also shows how to remove the encoder, in case you want to use it in a project without the motor.<br />
<br />
The two motor power leads are wound through a ferrite toroid to suppress EMI "noise."<br />
<br />
Here you can find a [[Media:globe-cad.pdf|cad file]] describing this actuator, a [[Media:HEDS5500-encoder.pdf|datasheet]] for the encoder, and a [[Media:idss-connector.pdf|datasheet]] for the Samtec IDSS-05-D-12.00 connector.<br />
<br />
<br clear=all><br />
<br />
===GM3 and GM9 Gearmotors===<br />
<br />
[[image:GM3.png|right]]<br />
<br />
'''Summary:''' (GM3 pictured at right)<br />
* rated at 6V, approx 10 ohms resistance<br />
* 224:1 gearhead (GM3) or 143:1 gearhead (GM9)<br />
* max speed at 6V approximately 43 RPM (GM3) or 84 RPM (GM9)<br />
* stall torque at 6V approximately 73 oz-in (GM3) or 52 oz-in (GM9)<br />
* no encoder installed, but can be modified to add one; see [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|here]]<br />
* size: 70 x 22.5 x 37 mm<br />
<br clear=all><br />
<br />
These highly-geared motors can be bought new at [http://www.solarbotics.com solarbotics.com] or [http://www.hobbyengineering.com hobbyengineering.com]. These motors work with these [http://www.solarbotics.com/products/gmpw/ wheels], which we have in<br />
the lab. The motors do not come with encoders, but you can [[Adding_a_magnetic_encoder_to_a_GM3_Gearmotor|add one yourself]],<br />
similar to the magnetic encoder on the Faulhaber motor above.<br />
<br />
<br clear=all><br />
<br />
==Stepper Motors==<br />
<br />
Stepper motors move in discrete steps. The controller energizes electromagnet<br />
coils, and the motor's rotor rotates to the nearest equilibrium point. By<br />
proper sequencing of which coils are energized, the motor rotates as desired<br />
(and, if the rotation is fast enough, may simply pass through the equilibrium<br />
points without stopping). <br />
<br />
One nice thing about stepper motors is that they do not require<br />
feedback; we know how far the motor has rotated, because we commanded<br />
the motion. This becomes a problem if we try to rotate the motor too<br />
fast, or if the load is larger than expected --- the motor may not<br />
actually do what we commanded. Stepper motors are a <br />
good choice for relatively low-torque applications where the loads<br />
are consistent, so we can be assured our commanded motions are followed.<br />
<br />
===Jameco 163395 8.4V bipolar stepper motor===<br />
<br />
[[image:small-stepper.jpg|right]]<br />
<br />
Although this motor is rated at 8.4V, it is possible<br />
to run it at lower or slightly higher voltages.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 8.4V, 2 phases, 30 ohms resistance, 280 mA current<br />
* holding torque: 0.081 Nm (coils energized)<br />
* detent torque: 0.0037 Nm (coils off)<br />
* size: 1.64" motor diameter, 1.2" motor height<br />
* shaft: 0.29" x 0.155" diameter<br />
* mass: 0.24 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-163395.pdf|data sheet]].<br />
There are four leads, two for each independent coil.<br />
<br />
<br clear=all><br />
<br />
===Jameco 162026CX 12V unipolar stepper motor===<br />
<br />
[[image:stepper-small.jpg|right]]<br />
<br />
If you need more holding torque, this stepper may be a<br />
good choice.<br />
<br />
* 1.8 deg/step (0.9 deg/half step)<br />
* 12V, 4 phases, 20 ohms resistance, 600 mA current<br />
* holding torque: 0.588 Nm (coils energized)<br />
* detent torque: 0.071 Nm (coils off)<br />
* size: 2.2" motor diameter, 2.0" motor height<br />
* shaft: 1" x 0.25" diameter<br />
* mass: 0.65 kg<br />
<br />
More information can be found on this<br />
[[Media:jameco-stepper-162026.pdf|data sheet]] (ours is the <br />
57BYG084). There are six leads, three for each independent<br />
coil.<br />
<br />
<br clear=all><br />
<br />
==RC Servo Motors==<br />
<br />
RC servos are convenient for positioning applications that require<br />
significant torque, not much speed, and only moderate positioning<br />
precision. They take three connections, power (+5V, typically),<br />
ground, and a pulsing signal that tells the motor the desired angle (typically a<br />
pulse of 0.5 - 3 ms every 20 ms or so, where the duration of the pulse<br />
indicates the desired angle of the motor).<br />
Inside the motor is a potentiometer that senses the actual angle of<br />
the motor output shaft and a feedback controller that tries to make<br />
the motor angle match that specified by the pulsed signal. There is<br />
also a large gear ratio such that the motor provides high torque at<br />
low speed. Most RC servos have limited angle range, like 180 degrees,<br />
due to the angle-sensing potentiometer.<br />
<br />
<br />
===Futaba S3004 standard ball bearing RC servo motor===<br />
<br />
[[image:RC-servo-small.jpg|right]]<br />
<br />
* motor rotation: 180 degrees<br />
* speed: 60 degrees in 0.23 sec at 4.8V, 0.19 sec at 6V<br />
* torque: 0.31 Nm at 4.8V, 0.4 Nm at 6V<br />
* size: 1.4" height, 0.8" width<br />
* mass: 37.2 g<br />
<br />
These were purchased from Tower Hobbies, part number LM1954.<br />
Higher torque versions are also available.<br />
<br />
<br clear=all><br />
<br />
==Solenoids==<br />
<br />
<br />
<br />
Solenoids are simple on-off actuators consisting of a plunger moving in an<br />
electromagnetic field. If you power the electromagnet, the plunger is<br />
"pushed" or "pulled" a particular stroke length, and if you unpower the<br />
coil, the plunger returns to its original position, usually by a return <br />
spring or gravity. These are simple to control and useful for applications<br />
where the actuator only has to take one of two positions. <br />
<br />
<br />
We stock two solenoids (in addition to many random ones) which are basically<br />
the same, except one is a "pull type" solenoid and the other is a "push type."<br />
<br />
===Jameco 262262 (pull) and 262271 (push) 12V open frame solenoid===<br />
<br />
[[image:solenoids-small.jpg|right]]<br />
<br />
* 12 V, 36 ohm resistance, 333 mA<br />
* holding force: 0.5 N<br />
* stroke: 6 mm<br />
* size: 1.5" length x 1.0" x 0.8" diameter<br />
* shaft diameter: 0.310"<br />
* mass: 96 g<br />
<br />
You can find a data sheet [[Media:jameco-solenoid-262262.pdf|here]].<br />
You can attach a lever (or other mechanical transformer) to the plunger to<br />
get more stroke and less force, or more force and less stroke. If no lever<br />
will meet your specs,<br />
then you will need another solenoid.<br />
<br />
<br />
==AC Motors==<br />
<br />
[[image:ac-servo-small.jpg|right]]<br />
<br />
Some projects need more power than any of the actuators above can<br />
provide. In that case, you may be able to use a Yaskawa AC motor.<br />
These are technically in the Laboratory for Intelligent Mechanical<br />
Systems, but they are available for Mechatronics use. These should<br />
not be a first choice, as (1) they can be dangerous due to their high<br />
power, and (2) they limit the mobility of your project as they must be<br />
plugged into the wall to get 110V AC. You can find information<br />
on these motors and their amplifiers<br />
[http://www.mech.northwestern.edu/courses/433/Writeups/YaskawaMotors/YakawaACservomotors.htm here].</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Opto-isolators&diff=9710Opto-isolators2009-01-12T20:51:33Z<p>MattT: </p>
<hr />
<div>Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation. <br />
<br />
An opto-isolator is a small [[Using_LEDs_%26_IREDs|LED]] in close proximity to a [[Photodiodes_and_Phototransistors|phototransistor]]. The LED is driven by the transmitting circuit and an appropriate resistor is necessary, see the opto-isolator data sheet for assistance is sizing this. The phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.<br />
<br />
The opto-isolators in the mechatronics lab (4N27) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher output to input current ratios, use an opto-isolator with a Darlington transistor pair in the output.<br />
<br />
Opto-isolators do not output square waves. For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N27 and has a bandwidth of 20 KHz.<br />
<br />
[[Image:Opto-isolator.jpg]]<br />
<br />
[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here] is a great resource for further information and additional higher bandwidth circuit diagrams.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Strain_Gauge&diff=9706Strain Gauge2009-01-12T20:38:06Z<p>MattT: /* Example Usage */</p>
<hr />
<div>===Overview===<br />
Strain gauges are simple sensors that can be used to measure forces. They consist peice of conducting material that changes resistance as it is stretched in a given direction. The diagram below shows this:<br />
<br />
[[image:strain gauge.jpg|center]]<br />
<br />
===Circuitry===<br />
Typically, the change in resistance of the strain gauge is very small. In order to accurately measure this small change, special circuitry is needed. For this, a ''wheatstone bridge'' configuration is usually employed. There are variants on how this circuit can be arranged; two are presented below.<br />
<br />
The first configuration is the simplest method. The wheatstone bridge measures small imbalances in the resistances. Here it is comparing the strain gauge resistance to <math>R_3</math>, which has a resistance equal to the resistance of the unstretched strain gauge. The other two resistors should have similar values.<br />
<br />
[[image:simple strain guage circuit.jpg|center]]<br />
<br />
Next is a more advanced circuit used for measuring strain in both directions. Two strain gauges are used, and must be positioned carefully, as shown in the second figure.<br />
<br />
{| align="center"<br />
|-<br />
| [[image:advanced strain gauge circuit.jpg|300px]]<br />
| [[image:advanced strain gauge attachment.jpg|300px]]<br />
|}<br />
<br />
<br />
===Example Usage===<br />
The FX1901 is an inexpensive 1% strain gauge that can be used for a variety of applications. It is available for about $30 and comes in 10, 25, 50, and 100 lbf models<br />
<br />
[[image:FX1901.jpg]]<br />
<br />
Here is an example set up circuit with amplifier amp and tuning potentiometer:<br />
<br />
[[image:ForceSensorCircuitDiagram.jpg]]<br />
<br />
Ensure that the power lines are very stable, it is suggested that in noisy environments, a DC-DC converter, power regulator(L78L05) and large power capacitors are used to ensure clean signal. In more ideal environments, a simple capacitor across the power lines should be sufficient.<br />
<br />
==References==<br />
* http://www.allaboutcircuits.com/vol_1/chpt_9/7.html/strain_gauges</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Opto-isolators&diff=9704Opto-isolators2009-01-12T20:21:51Z<p>MattT: </p>
<hr />
<div>Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation. <br />
<br />
An opto-isolator is a small [[Using_LEDs_%26_IREDs|LED]] in close proximity to a [[Photodiodes_and_Phototransistors|phototransistor]]. The LED is driven by the transmitting circuit and an appropriate resistor is necessary, see the opto-isolator data sheet for assistance is sizing this. The phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.<br />
<br />
The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher output to input current ratios, use an opto-isolator with a Darlington transistor pair in the output.<br />
<br />
Opto-isolators do not output square waves. For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.<br />
<br />
[[Image:Opto-isolator.jpg]]<br />
<br />
[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here] is a great resource for further information and additional higher bandwidth circuit diagrams.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Opto-isolators&diff=9703Opto-isolators2009-01-12T20:21:04Z<p>MattT: </p>
<hr />
<div>Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation. <br />
<br />
An opto-isolator is a small [[Using_LEDs_%26_IREDs|LED]] in close proximity to a [[Photodiodes_and_Phototransistors|phototransistor]]. The LED is driven by the transmitting circuit and an appropriate resistor is necessary, see the opto-isolator data sheet for assistance is sizing this. The phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.<br />
<br />
The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.<br />
<br />
Opto-isolators do not output square waves. For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.<br />
<br />
[[Image:Opto-isolator.jpg]]<br />
<br />
[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here] is a great resource for further information and additional higher bandwidth circuit diagrams.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Opto-isolators&diff=9702Opto-isolators2009-01-12T20:17:19Z<p>MattT: </p>
<hr />
<div>Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation. <br />
<br />
An opto-isolator is a small LED in close proximity to a phototransistor. The LED is driven by the transmitting circuit, while the phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.<br />
<br />
The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.<br />
<br />
Opto-isolators do not output square waves. For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.<br />
<br />
[[Image:Opto-isolator.jpg]]<br />
<br />
[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here] is a great resource for further information and additional higher bandwidth circuit diagrams.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Strain_Gauge&diff=9687Strain Gauge2009-01-09T05:12:04Z<p>MattT: /* Example Usage */</p>
<hr />
<div>===Overview===<br />
Strain gauges are simple sensors that can be used to measure forces. They consist peice of conducting material that changes resistance as it is stretched in a given direction. The diagram below shows this:<br />
<br />
[[image:strain gauge.jpg|center]]<br />
<br />
===Circuitry===<br />
Typically, the change in resistance of the strain gauge is very small. In order to accurately measure this small change, special circuitry is needed. For this, a ''wheatstone bridge'' configuration is usually employed. There are variants on how this circuit can be arranged; two are presented below.<br />
<br />
The first configuration is the simplest method. The wheatstone bridge measures small imbalances in the resistances. Here it is comparing the strain gauge resistance to <math>R_3</math>, which has a resistance equal to the resistance of the unstretched strain gauge. The other two resistors should have similar values.<br />
<br />
[[image:simple strain guage circuit.jpg|center]]<br />
<br />
Next is a more advanced circuit used for measuring strain in both directions. Two strain gauges are used, and must be positioned carefully, as shown in the second figure.<br />
<br />
{| align="center"<br />
|-<br />
| [[image:advanced strain gauge circuit.jpg|300px]]<br />
| [[image:advanced strain gauge attachment.jpg|300px]]<br />
|}<br />
<br />
<br />
===Example Usage===<br />
The FX1901 is an inexpensive 1% strain gauge that can be used for a variety of applications. It is available for about $30 and comes in 10, 25, 50, and 100 lbf models<br />
<br />
[[image:FX1901.jpg]]<br />
<br />
Here is an example set up circuit with amplifier amp and tuning potentiometer:<br />
<br />
[[image:ForceSensorCircuitDiagram.jpg]]<br />
<br />
==References==<br />
* http://www.allaboutcircuits.com/vol_1/chpt_9/7.html/strain_gauges</div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:ForceSensorCircuitDiagram.jpg&diff=9686File:ForceSensorCircuitDiagram.jpg2009-01-09T05:11:31Z<p>MattT: </p>
<hr />
<div></div>MattThttps://hades.mech.northwestern.edu//index.php?title=Strain_Gauge&diff=9685Strain Gauge2009-01-09T05:11:08Z<p>MattT: /* Example Usage */</p>
<hr />
<div>===Overview===<br />
Strain gauges are simple sensors that can be used to measure forces. They consist peice of conducting material that changes resistance as it is stretched in a given direction. The diagram below shows this:<br />
<br />
[[image:strain gauge.jpg|center]]<br />
<br />
===Circuitry===<br />
Typically, the change in resistance of the strain gauge is very small. In order to accurately measure this small change, special circuitry is needed. For this, a ''wheatstone bridge'' configuration is usually employed. There are variants on how this circuit can be arranged; two are presented below.<br />
<br />
The first configuration is the simplest method. The wheatstone bridge measures small imbalances in the resistances. Here it is comparing the strain gauge resistance to <math>R_3</math>, which has a resistance equal to the resistance of the unstretched strain gauge. The other two resistors should have similar values.<br />
<br />
[[image:simple strain guage circuit.jpg|center]]<br />
<br />
Next is a more advanced circuit used for measuring strain in both directions. Two strain gauges are used, and must be positioned carefully, as shown in the second figure.<br />
<br />
{| align="center"<br />
|-<br />
| [[image:advanced strain gauge circuit.jpg|300px]]<br />
| [[image:advanced strain gauge attachment.jpg|300px]]<br />
|}<br />
<br />
<br />
===Example Usage===<br />
The FX1901 is an inexpensive 1% strain gauge that can be used for a variety of applications. It is available for about $30 and comes in 10, 25, 50, and 100 lbf models<br />
<br />
[[image:FX1901.jpg]]<br />
<br />
[[image:ForceSensorCircuitDiagram.jpg]]<br />
<br />
Here is an example set up circuit with amplifier amp and tuning potentiometer.<br />
<br />
==References==<br />
* http://www.allaboutcircuits.com/vol_1/chpt_9/7.html/strain_gauges</div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:FX1901_Diagram.jpg&diff=9671File:FX1901 Diagram.jpg2009-01-07T04:52:17Z<p>MattT: </p>
<hr />
<div></div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:FX1901.jpg&diff=9670File:FX1901.jpg2009-01-07T04:52:01Z<p>MattT: </p>
<hr />
<div></div>MattThttps://hades.mech.northwestern.edu//index.php?title=Strain_Gauge&diff=9669Strain Gauge2009-01-07T04:51:44Z<p>MattT: /* Example Usage */</p>
<hr />
<div>===Overview===<br />
Strain gauges are simple sensors that can be used to measure forces. They consist peice of conducting material that changes resistance as it is stretched in a given direction. The diagram below shows this:<br />
<br />
[[image:strain gauge.jpg|center]]<br />
<br />
===Circuitry===<br />
Typically, the change in resistance of the strain gauge is very small. In order to accurately measure this small change, special circuitry is needed. For this, a ''wheatstone bridge'' configuration is usually employed. There are variants on how this circuit can be arranged; two are presented below.<br />
<br />
The first configuration is the simplest method. The wheatstone bridge measures small imbalances in the resistances. Here it is comparing the strain gauge resistance to <math>R_3</math>, which has a resistance equal to the resistance of the unstretched strain gauge. The other two resistors should have similar values.<br />
<br />
[[image:simple strain guage circuit.jpg|center]]<br />
<br />
Next is a more advanced circuit used for measuring strain in both directions. Two strain gauges are used, and must be positioned carefully, as shown in the second figure.<br />
<br />
{| align="center"<br />
|-<br />
| [[image:advanced strain gauge circuit.jpg|300px]]<br />
| [[image:advanced strain gauge attachment.jpg|300px]]<br />
|}<br />
<br />
<br />
===Example Usage===<br />
The FX1901 is an inexpensive 1% strain gauge that can be used for a variety of applications. It is available for about $30 and comes in 10, 25, 50, and 100 lbf models<br />
<br />
[[image:FX1901.jpg]]<br />
<br />
[[image:FX1901 Diagram.jpg]]<br />
<br />
Connect the + input to Vcc and the - input to Vss. A signal conditioner then needs to be used to get the appropriate gain for output.<br />
<br />
==References==<br />
* http://www.allaboutcircuits.com/vol_1/chpt_9/7.html/strain_gauges</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Strain_Gauge&diff=9668Strain Gauge2009-01-07T04:51:25Z<p>MattT: /* Example Usage */</p>
<hr />
<div>===Overview===<br />
Strain gauges are simple sensors that can be used to measure forces. They consist peice of conducting material that changes resistance as it is stretched in a given direction. The diagram below shows this:<br />
<br />
[[image:strain gauge.jpg|center]]<br />
<br />
===Circuitry===<br />
Typically, the change in resistance of the strain gauge is very small. In order to accurately measure this small change, special circuitry is needed. For this, a ''wheatstone bridge'' configuration is usually employed. There are variants on how this circuit can be arranged; two are presented below.<br />
<br />
The first configuration is the simplest method. The wheatstone bridge measures small imbalances in the resistances. Here it is comparing the strain gauge resistance to <math>R_3</math>, which has a resistance equal to the resistance of the unstretched strain gauge. The other two resistors should have similar values.<br />
<br />
[[image:simple strain guage circuit.jpg|center]]<br />
<br />
Next is a more advanced circuit used for measuring strain in both directions. Two strain gauges are used, and must be positioned carefully, as shown in the second figure.<br />
<br />
{| align="center"<br />
|-<br />
| [[image:advanced strain gauge circuit.jpg|300px]]<br />
| [[image:advanced strain gauge attachment.jpg|300px]]<br />
|}<br />
<br />
<br />
===Example Usage===<br />
The FX1901 is an inexpensive 1% strain gauge that can be used for a variety of applications. It is available for about $30 and comes in 10, 25, 50, and 100 lbf models<br />
<br />
[[image:FX1901.jpg]<br />
<br />
Connect the + input to Vcc and the - input to Vss. A signal conditioner then needs to be used to get the appropriate gain for output.<br />
<br />
==References==<br />
* http://www.allaboutcircuits.com/vol_1/chpt_9/7.html/strain_gauges</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Strain_Gauge&diff=9667Strain Gauge2009-01-07T04:50:58Z<p>MattT: </p>
<hr />
<div>===Overview===<br />
Strain gauges are simple sensors that can be used to measure forces. They consist peice of conducting material that changes resistance as it is stretched in a given direction. The diagram below shows this:<br />
<br />
[[image:strain gauge.jpg|center]]<br />
<br />
===Circuitry===<br />
Typically, the change in resistance of the strain gauge is very small. In order to accurately measure this small change, special circuitry is needed. For this, a ''wheatstone bridge'' configuration is usually employed. There are variants on how this circuit can be arranged; two are presented below.<br />
<br />
The first configuration is the simplest method. The wheatstone bridge measures small imbalances in the resistances. Here it is comparing the strain gauge resistance to <math>R_3</math>, which has a resistance equal to the resistance of the unstretched strain gauge. The other two resistors should have similar values.<br />
<br />
[[image:simple strain guage circuit.jpg|center]]<br />
<br />
Next is a more advanced circuit used for measuring strain in both directions. Two strain gauges are used, and must be positioned carefully, as shown in the second figure.<br />
<br />
{| align="center"<br />
|-<br />
| [[image:advanced strain gauge circuit.jpg|300px]]<br />
| [[image:advanced strain gauge attachment.jpg|300px]]<br />
|}<br />
<br />
<br />
===Example Usage===<br />
The FX1901 is an inexpensive 1% strain gauge that can be used for a variety of applications. It is available for about $30 and comes in 10, 25, 50, and 100 lbf models<br />
<br />
[[image:FX1901.jpg]<br />
[[image:FX1901 Diagram.jpg]<br />
<br />
Connect the + input to Vcc and the - input to Vss. A signal conditioner then needs to be used to get the appropriate gain for output.<br />
<br />
<br />
==References==<br />
* http://www.allaboutcircuits.com/vol_1/chpt_9/7.html/strain_gauges</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Bearings&diff=9666Bearings2009-01-07T04:24:49Z<p>MattT: /* Sliding Bearings */</p>
<hr />
<div>==Types of Bearings==<br />
<br />
===Rolling-Element Bearings===<br />
<br />
There are several types of rolling-element bearings. These bearings make contact by some small rolling element such as a ball or cylinder. Below are common rolling-element brearings and their cross-section designation.<br />
<br />
{| align="center"<br />
! width="125px" | Radial Ball Bearing<br />
! width="125px" | Angular Ball Bearing<br />
! width="125px" | Spherical Ball Bearing<br />
! width="125px" | Needle Bearing<br />
! width="175px" | Thrust Bearing<br />
|-<br />
| [[image:radial ball bearing.png|100px|center]]<br />
| [[image:angular ball bearing.png|100px|center]]<br />
| [[image:spherical ball bearing.png|100px|center]]<br />
| [[image:needle bearing.png|100px|center]]<br />
| [[image:thrust bearing.png|150px|center]]<br />
|-<br />
| [[image:radial ball bearing crosssection.gif|center]]<br />
| [[image:angular ball bearing crosssection.gif|center]]<br />
| [[image:spherical ball bearing crosssection.gif|center]]<br />
| [[image:needle bearing crosssection.gif|center]]<br />
| [[image:thrust bearing crosssection.gif|center]]<br />
|}<br />
<br />
===Sliding Bearings===<br />
<br />
One type of sliding bearing is a pillow block bearing. These bearings allow for misalignment of shafts, but have smaller load ratings than ball bearings.<br />
<br />
[[Image:Pillow Block.jpg|center]]<br />
<br />
==Bearing Selection==<br />
<br />
===Cylindrical Bearing Selection===<br />
<br />
===Thrust Bearing Selection===<br />
<br />
<br />
==References==<br />
* The Timken Company, http://www.timken.com</div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:Pillow_Block.jpg&diff=9665File:Pillow Block.jpg2009-01-07T04:23:42Z<p>MattT: Pillow Block</p>
<hr />
<div>Pillow Block</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Bearings&diff=9664Bearings2009-01-07T04:23:20Z<p>MattT: /* Sliding Bearings */</p>
<hr />
<div>==Types of Bearings==<br />
<br />
===Rolling-Element Bearings===<br />
<br />
There are several types of rolling-element bearings. These bearings make contact by some small rolling element such as a ball or cylinder. Below are common rolling-element brearings and their cross-section designation.<br />
<br />
{| align="center"<br />
! width="125px" | Radial Ball Bearing<br />
! width="125px" | Angular Ball Bearing<br />
! width="125px" | Spherical Ball Bearing<br />
! width="125px" | Needle Bearing<br />
! width="175px" | Thrust Bearing<br />
|-<br />
| [[image:radial ball bearing.png|100px|center]]<br />
| [[image:angular ball bearing.png|100px|center]]<br />
| [[image:spherical ball bearing.png|100px|center]]<br />
| [[image:needle bearing.png|100px|center]]<br />
| [[image:thrust bearing.png|150px|center]]<br />
|-<br />
| [[image:radial ball bearing crosssection.gif|center]]<br />
| [[image:angular ball bearing crosssection.gif|center]]<br />
| [[image:spherical ball bearing crosssection.gif|center]]<br />
| [[image:needle bearing crosssection.gif|center]]<br />
| [[image:thrust bearing crosssection.gif|center]]<br />
|}<br />
<br />
===Sliding Bearings===<br />
<br />
One type of sliding bearing is a pillow block bearing. These bearings allow for misalignment of shafts, but have smaller load ratings than ball bearings.<br />
<br />
[[Image:Pillow Block.jpg]]<br />
<br />
==Bearing Selection==<br />
<br />
===Cylindrical Bearing Selection===<br />
<br />
===Thrust Bearing Selection===<br />
<br />
<br />
==References==<br />
* The Timken Company, http://www.timken.com</div>MattThttps://hades.mech.northwestern.edu//index.php?title=File:Opto-isolator.jpg&diff=9663File:Opto-isolator.jpg2009-01-07T04:09:23Z<p>MattT: An opto-ispolator using the 4N270545K with a 20KHz bandwidth.</p>
<hr />
<div>An opto-ispolator using the 4N270545K with a 20KHz bandwidth.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Opto-isolators&diff=9662Opto-isolators2009-01-07T04:06:20Z<p>MattT: </p>
<hr />
<div>Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation. <br />
<br />
An opto-isolator is a small LED in close proximity to a phototransistor. The LED is driven by the transmitting circuit, while the phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.<br />
<br />
The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.<br />
<br />
Opto-isolators do not output square waves. For this reason, a comparator is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.<br />
<br />
[[Image:Opto-isolator.jpg]]<br />
<br />
[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here] is a great resource for further information and additional higher bandwidth circuit diagrams.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Opto-isolators&diff=9661Opto-isolators2009-01-07T04:05:58Z<p>MattT: </p>
<hr />
<div>Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation. <br />
<br />
An opto-isolator is a small LED in close proximity to a phototransistor. The LED is driven by the transmitting circuit, while the phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.<br />
<br />
The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.<br />
<br />
Opto-isolators do not output square waves. For this reason, a comparator is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.<br />
<br />
[[Image:Opto-isolator.jpg]]<br />
<br />
[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here]Here is a great resource for further information and additional higher bandwidth circuit diagrams.</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Main_Page&diff=9659Main Page2009-01-07T02:43:10Z<p>MattT: </p>
<hr />
<div>The Northwestern University mechatronics design wiki provides reference material on the theory and applications of electronics, sensors, actuators, etc., for use in mechatronics-related research and projects. Practical applications often refer to equipment and supplies available in the [http://mechatronics.mech.northwestern.edu/ Northwestern Mechatronics Design Lab].<br />
<br />
Important: Please be sure to read the [http://mechatronics.mech.northwestern.edu/mech-rules.pdf Rules for Using the Mechatronics Design Lab].<br />
<br />
<br />
__TOC__<br />
<br />
<br />
<br />
<br />
<h3>Design Competition 2008</h3><br />
<br />
Wiki pages on sensors, actuators, programming, and microcontrollers: use pages below<br />
<br><br />
* [http://www.mech.northwestern.edu/courses/433/Writeups/QuickStart/ Parts in the DC2008 quick start pack]<br />
* [http://peshkin.mech.northwestern.edu/pic/info/piccintro_2008-01-24.pdf PIC C intro slides, as presented 2008/01/24 (pdf)]<br />
* [http://peshkin.mech.northwestern.edu/pic/info/picinterfacing_2008-01-28.pdf PIC interfacing slides, as presented 2008/01/28 (pdf)]<br />
<br><br />
<br />
<h3>Sensors and actuators for DC</h3><br />
* [[Using Solderless Breadboard|Solderless Breadboard & wiring that works]]<br />
* [[Using LEDs & IREDs]]<br />
* [[Using a laser]]<br />
* [[Sensing optical tape|Infrared reflectivity]]<br />
** Using phototransistors<br />
** Sensing optical tape<br />
* [[Comparators | Comparators : the analog digital interface]]<br />
* [http://www.robotroom.com/FaulhaberGearmotor.html Faulhaber MiniMotor SA gearmotor with encoder], as well as [[Actuators_Available_in_the_Mechatronics_Lab#Faulhaber_1524E006S_motor_with_141:1_gearhead_and_HES164A_magnetic_quadrature_encoder|the local wiki page]]<br />
* [[Adding a magnetic encoder to a GM3 Gearmotor]]<br />
** Using magnetic switches (Hall Effect)<br />
* [[High-current devices|Driving high-current devices: several options]]<br />
* [[Driving a Stepper Motor]]<br />
* [[Driving an RC Servo]]<br />
* [[Accelerometers]]<br />
* [[Strain gauges]]<br />
* [[Using the Basic Stamp Microcontroller|Basic Stamp Microcontroller]] <b>Not recommended for DC2008</b><br />
* [http://www.mech.northwestern.edu/courses/433/Writeups/Battery_NiMH/ NiMH rechargable batteries and chargers]<br />
<br />
<h3> [http://peshkin.mech.northwestern.edu/datasheets Prof. Peshkin's favorite datasheets]</h3><br />
<br><br />
<br />
<h3>PIC 18F4520 prototyping board </h3><br />
*[[4520 Board intro|Prototyping board intro]]<br />
*[[4520 Board construction|Assembling the 18F4520 prototyping board, circuit, parts]]<br />
*[[4520 Board use|Using the 18F4520 prototyping board]]<br />
<br><br />
<br />
<h3>Programming with CCS C </h3><br />
*[[C language|The C language]]<br />
*[[CCS C|CCS C, specifically for the 18F4520]]<br />
*[[Embedded Programming Tips for CCS C]]<br />
*[[CCS IDE|Using the CCS development environment]]<br />
*[[Debugging C on a PIC]]<br />
*[[More debugging tips]]<br />
*[http://www.ccsinfo.com/forum/ CCS user forum]<br />
<br><br />
<br />
<h3>Interfacing and skeleton code for the PIC 18F4520</h3><br><br />
<b>These topics have wiki pages <i>and</i> sample code available</b><br><br />
<b>[http://peshkin.mech.northwestern.edu/pic/code Link to all sample code here.]</b><br />
<br><br />
* [[Digital inputs & outputs]] (filename: DigitalIO)<br />
* [[Analog Input]] (filename: AnalogInput)<br />
** reading a trimpot<br />
** reading a phototransistor<br />
** amplified phototransistor, and IRED strobing<br />
** using an instrumentation amp (example: for a strain gauge)<br />
* [[Analog Output|Analog Output, and the I2C bus]] (filename: AnalogOutput)<br />
* [[Waveform Generation with AD9833]] (filename: AD9833)<br />
* [[SPI - Serial Peripheral Interface - on the PIC]]<br />
*[[Pulse width modulation|Pulse width modulation (PWM) for driving motors or other high current devices]] (filename: MotorPWM)<br />
** using H-bridges<br />
* [[Interrupts]]<br />
* [[Quadrature decoding in software]] (filename: QuadratureSoft)<br />
* [[Quadrature decoding in hardware, or just counters]] (filename: QuadratureHard)<br />
* [[Running RC servos]] (filename: RCservoSoft & RCservoHard)<br />
* [[Watchdog timer]] (filename: Watchdog)<br />
* [[PIC RS232|RS-232 serial communication between a PC and a PIC]] (filename: RS232)<br />
* [[C Example: Serial LCD|Text output to a serial LCD display]]<br />
* [[C Example: Parallel Interfacing with LCDs|Text output to a parallel LCD display]]<br />
* [[Servo skeleton with fast & slow interrupts]]<br />
* [[XBee radio communication between PICs]] (and between a PC and a PIC)<br />
* [[I2C communication between PICs]]<br />
* [[Serial communication with Matlab]]<br />
* [[SPI communication between PICs]] <b> (Note: this function has not been successfully tested)</b><br />
* [[Microphones]]<br />
* [[Ambient light color sensing]]<br />
* [[Controlling a seven segment display]]<br />
* [[Storing constant data in program memory]]<br />
* [[PIC computation time benchmarks]]<br />
* [[Stepper motor control with the PIC]]<br />
* [[Global Positioning System]]<br />
* [[IR communication between PICs]] <b> (Note: this function has not been successfully tested) </b><br />
* [[Interfacing to External EEPROM]]<br />
* [[I2C Motor Controller]]<br />
* [[Interfacing with a Photodiode Array]]<br />
<br />
<br><br />
<b>These topics have sample code available, but no wiki pages yet</b><br><br />
<b>[http://peshkin.mech.northwestern.edu/pic/code Link to all sample code here.]</b><br />
<br />
* Counter0 - Counting pulses with Timer0]<br />
* Counter1 - Counting pulses with Timer1]<br />
* Interrupt0 - Periodic servo cycles using interrupt routines, 10mS & slower; Timer 0]<br />
* Interrupt2 - Periodic servo cycles using interrupt routines; 10mS & faster; Timer 2]<br />
* InterruptExternal - Interrupts generated by an external pulse]<br />
<br />
<br><br />
<b>These topics need more development</b><br><br />
<b>[http://peshkin.mech.northwestern.edu/pic/code Link to all sample code here.]</b><br><br />
* AnalogOutputParallel - Analog output using 8 digital lines]<br />
* PIC-to-PIC communication <br />
* Zigbee radio communication<br />
* Modulated IR communication<br />
* Strobing LEDs or IREDs for better range and immunity to background light<br />
* I2C communication <br />
* CAN bus<br />
* Capturing data to Matlab<br />
* Running stepper motors<br />
<br><br />
<br />
<h3>PIC Microcontrollers</h3><br />
* [[PIC Microcontrollers with CCS Compiler]], for DC, 333, etc, using the CCS ICD-U40 device <b>[this section has been replaced by the material above]</b><br />
* [[PIC Microcontrollers with C18 Compiler]], for e-puck, or using the Microchip ICD device or<br />
<br><br />
<br />
<h3>e-puck Mobile Robot</h3><br />
* [[e-puck Mobile Robot]]<br />
<br><br />
<br />
<h3>[[Printing Circuit Boards]]</h3><br />
<br />
* [[PCB Artist | PCB Artist: Software provided by Advanced Circuits]]<br />
<br />
<h3> Electronics </h3><br />
* [http://hades.mech.northwestern.edu/wiki/index.php/Category:Electronics Electronics]<br />
* [[Phase-Sensitive Detection]]<br />
* [http://en.wikipedia.org/wiki/Operational_amplifier_applications Op-Amp Applications]<br />
<br><br />
<br />
<h3>Analog and Digital chips</h3><br />
* [[Comparators | Comparators: the analog to digital interface]]<br />
* [[Filtering with the LMF100 | Filtering with the LMF100]]<br />
* [http://en.wikipedia.org/wiki/Operational_amplifier_applications Opamps : building blocks of analog computation]<br />
* [http://www.mech.northwestern.edu/courses/433/Writeups/InstAmp/instamp.htm Instrumentation amps, and NU circuit board for them]<br />
* [[LED Drivers | Controlling large numbers of LEDs with LED drivers]]<br />
* [[Opto-isolators | Opto-isolators: Signal transfer while electrically isolating circuits]]<br />
<br />
<br clear=all/><br />
<br />
<h3>[[:Category:Sensors|Sensors]]</h3><br />
<br />
* [[Potentiometers|Angle, Linear Position: Potentiometers]]<br />
* [[Optointerrupter|Beam Breaker: Optointerrupter]]<br />
* [[Optoreflector|Proximity: Optoreflector]]<br />
* [[Sensing optical tape|Infrared reflectivity : Sensing optical tape]]<br />
* [[Reed Switch|Proximity: Reed Switch]]<br />
* [[Hall Effect Sensor|Proximity, Angle: Hall Effect Sensor]]<br />
* [[Rotary Encoder|Angle: Rotary Encoder]]<br />
* Angular Velocity: Tachometer<br />
* [[Photodiodes and Phototransistors|Light: Photodiodes and Phototransistors]]<br />
* [[Photocell|Ambient Light: Photocell]]<br />
* [[Thermistor|Temperature: Thermistor]]<br />
* Temperature: Thermotransistor IC<br />
* Audio: [[Microphones]]<br />
* [[Accelerometers|Tilt, Acceleration: Accelerometers]]<br />
* [[Strain Gauge|Force: Strain Gauge]]<br />
* Current: Current Sense Resistor<br />
* [[Limit Switch|Contact: Microswitch (Limit Switch)]]<br />
* [[Ambient light color sensing]]<br />
* [[Global Positioning System]]<br />
* [[Optics]]<br />
* [[Optical Locating]]<br />
* [[Lateral-Effect Photodiode]]<br />
* [[IR Target Illumination|IRED's]]<br />
<br />
<br clear=all/><br />
<br />
<h3>[[:Category:Actuators|Actuators]]</h3><br />
[[image:All-actuators-captions-small.jpg|thumb|300px|[[Actuators Available in the Mechatronics Lab|Available Actuators]]|right]]<br />
<br />
* [[Brushed DC Motor Theory|Brushed DC Motors]]<br />
** [[Choosing a Motor and Gearing Combination|Choosing a Motor and Gearing Combination]]<br />
** [[Linear Amplifier Motor Driver|Driving Using a Linear Amplifier]]<br />
** [[Driving using a single MOSFET|Driving using a single MOSFET]]<br />
** [[Pulse Width Modulation|Driving Using Pulse Width Modulation]]<br />
** [[PIC PWM Motor Driver]]<br />
** [[Gear Motor]]<br />
** [[Pulse Width Modulation]]<br />
** [[Pulse_width_modulation]]<br />
** [[Driving using a single MOSFET | Driving a DC motor using a single MOSFET]]<br />
** [[Driving a DC Motor using PWM]]<br />
** [[Driving a high current DC Motor using an H-bridge]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/AddEncoderHobbyEngGearMotor Adding a rotation encoder to a gearmotor]<br />
** [[Using Opto-Isolators to Prevent Interference]]<br />
* [[Brushless DC Motors]]<br />
** [[Driving Brushless DC Motors]]<br />
* [[Stepper Motor Theory|Stepper Motors]]<br />
** [[Stepper Motor Circuits|Driving Stepper Motors]]<br />
** [[Unipolar Stepper Motor Driver Circuit]]<br />
** [[Bipolar Stepper Motor Driver Circuit]]<br />
* [[RC Servo Theory|RC Servos]]<br />
** [[555 Servo Circuit|Driving Your Servo Using a 555 Timer]]<br />
* [[Solenoid Theory|Solenoids]]<br />
** Practice: Driving Your Solenoid<br />
* AC Motors<br />
** [[Using the Yaskawa Motors]]<br />
* [[Fans As Actuators|Fans As Actuators]]<br />
* [[LIMS Air Hockey Table|LIMS Air Hockey Table]]<br />
* [[Actuators Available in the Mechatronics Lab]]<br />
<br clear=all/><br />
<br />
<h3>Mechanical Design</h3><br />
*Mechanics of Materials<br />
**Beam Mechanics<br />
**[[Mohr's Circle]]<br />
*Failure Theories<br />
**Static Loading<br />
**Variable Loading and Fatigue<br />
*Fastening<br />
**Nuts and Bolts<br />
**Keys and Keyways<br />
**Press-fits<br />
**Set Screws<br />
*Support<br />
**Housings<br />
**Shafts<br />
**[[Bearings]]<br />
*Transmission<br />
**Rigid: [[Gears]]<br />
**Flexible: Belts, Chains<br />
**Motion Connection/Separation: Clutches, Brakes, Couplings<br />
*Linkages<br />
**Serial Chains<br />
**Parallel and Closed-Loop Chains<br />
*Other: springs/dampers, cams, etc.<br />
<br />
<br clear=all/><br />
<br />
<h3>The PC/104 Stack</h3><br />
[[Image:Img0174.jpg|thumb|300px|[[PC104 Overview|The PC104 Stack]]|right]]<br />
* [[PC104 Overview|Overview]]<br />
* [[The PC/104 Lab Kit]]<br />
* Hardware:<br />
** [[Advantech CPU Card]]<br />
** [[Sensoray 526 Data Aquisition Card]]<br />
<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#power[Power Components]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#electrical[I/O Electronics: Analog I/O, Digital I/O, Encoder Connections]]<br />
* Advanced: Creating a Working Stack from Parts<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm [Building the Breakout Board]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#ribboncables[Breakout Board Ribbon Cables]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#mechanical[Assembling the PC104 Stack]]<br />
** '''[[Creating an xPC Flash Boot Disk]]''' <- when new version of MATLAB<br />
* Custom Boards<br />
** Dual PWM Motor Controller<br />
** Dual Linear Amplifier Motor Controller<br />
<br clear=all/><br />
<br />
<h3>xPC Target Real-Time Operating System</h3><br />
<br />
* [[xPC Overview|Overview of Real-Time Programming with Simulink and xPC Target]]<br />
* [[Configuring xPC Target PC|Configuring xPC Host/Target PC]]<br />
* [[Creating a Simple xPC Program|'''Quickstart''':Creating a simple xPC Program]]<br />
* [[Common xPC Blocks|Commonly Used Blocks]]<br />
* [[Using the Host Scope]]<br />
*Advanced<br />
** Model Properties<br />
** [[XPC M-file Communication|M-file communication]]<br />
** Using outside of the lab<br />
** [[media:standalone.pdf|Standalone Mode]]<br />
** Stateflow<br />
* Code Examples<br />
** [[Controlling a DC Motor with an Encoder]]<br />
** Something With State Machine<br />
** [[Using RS-232 and Printing to LCD]]<br />
**[[UDP Communications between Target and Host PC]]<br />
** M-functions and S-functions<br />
** [[xPC Code From Student Projects]]<br />
<br clear=all/><br />
<br />
<h3>QNX Real-Time Operating System</h3><br />
*[[media:qnxtemplate.zip|QNX Control Program with Interrupts]]<br />
<br />
<br clear=all/><br />
<br />
<h3>Lab Supplies and Data Sheets</h3><br />
<br />
* [http://spreadsheets.google.com/pub?key=pa_bNAhFF-OvvxpSje1KDYg&output=html&gid=0&single=true Generally stocked lab inventory ]<br />
<br />
<br clear=all><br />
<br />
<h3>[[Vendors]]</h3><br />
<br />
<br clear=all><br />
<br />
<h3>Other Software</h3><br />
*[[List of Useful Software for Download]]<br />
*Circuit Schematics and PCB Layout<br />
*LaTex Document Preparation<br />
** [http://meta.wikimedia.org/wiki/Help:Formula Mathematical Formulae]<br />
** Document Formatting<br />
** [[LaTeX Software Setup|Software Setup]]<br />
** IEEE Styles<br />
<br />
<br clear=all><br />
<br />
<h3>[[Other Lab Equipment]]</h3><br />
* Prototyping Tools<br />
** [[Tektronix TDS220 Oscilloscope]]<br />
** [[Tektronix CFG253 Function Generator]]<br />
** [[media:Mastech_power_supply_manual.pdf|Mastech Power Supply]]<br />
** Fluke III Multimeter<br />
** Benchtop Multimeter<br />
** Powered Breadboard<br />
** Soldering Iron<br />
* [http://ediacaran.mech.northwestern.edu/neuromech/index.php/Lab_Equipment High Performance Neuromechatronics Benches]<br />
* The Sensoray 626 DAQ Card<br />
<br />
<br clear=all><br />
<br />
<h3>Course Material</h3><br />
* [[ME 224 Experimental Engineering]]<br />
* [http://lims.mech.northwestern.edu/~lynch/courses/ME333/2008/index.html ME 333 Introduction to Mechatronics]<br />
** [[Lab 5]]<br />
** [[Suggested final projects]]<br />
** [[ME 333 final projects]]<br />
<!--<br />
* [http://www.mech.northwestern.edu/hartmann/ME333_CourseInformation.html ME 333 Mechatronics]<br />
--><br />
* [http://www.mech.northwestern.edu/courses/433/ ME 433 Advanced Mechatronics] <br />
<br />
<br clear=all><br />
<br />
<h3>Miscellaneous</h3><br />
* [[Swarm Robot Project]]<br />
** [[Swarm Robot Project Links]]<br />
<br />
* [[Indoor Localization System]]<br />
* [[Robot Helicopter Project]]<br />
* [[E-Puck Color Sensing Project]]<br />
* [[Guitar Tunning Project]]</div>MattThttps://hades.mech.northwestern.edu//index.php?title=Main_Page&diff=9658Main Page2009-01-07T02:42:27Z<p>MattT: </p>
<hr />
<div>The Northwestern University mechatronics design wiki provides reference material on the theory and applications of electronics, sensors, actuators, etc., for use in mechatronics-related research and projects. Practical applications often refer to equipment and supplies available in the [http://mechatronics.mech.northwestern.edu/ Northwestern Mechatronics Design Lab].<br />
<br />
Important: Please be sure to read the [http://mechatronics.mech.northwestern.edu/mech-rules.pdf Rules for Using the Mechatronics Design Lab].<br />
<br />
<br />
__TOC__<br />
<br />
<br />
<br />
<br />
<h3>Design Competition 2008</h3><br />
<br />
Wiki pages on sensors, actuators, programming, and microcontrollers: use pages below<br />
<br><br />
* [http://www.mech.northwestern.edu/courses/433/Writeups/QuickStart/ Parts in the DC2008 quick start pack]<br />
* [http://peshkin.mech.northwestern.edu/pic/info/piccintro_2008-01-24.pdf PIC C intro slides, as presented 2008/01/24 (pdf)]<br />
* [http://peshkin.mech.northwestern.edu/pic/info/picinterfacing_2008-01-28.pdf PIC interfacing slides, as presented 2008/01/28 (pdf)]<br />
<br><br />
<br />
<h3>Sensors and actuators for DC</h3><br />
* [[Using Solderless Breadboard|Solderless Breadboard & wiring that works]]<br />
* [[Using LEDs & IREDs]]<br />
* [[Using a laser]]<br />
* [[Sensing optical tape|Infrared reflectivity]]<br />
** Using phototransistors<br />
** Sensing optical tape<br />
* [[Comparators | Comparators : the analog digital interface]]<br />
* [http://www.robotroom.com/FaulhaberGearmotor.html Faulhaber MiniMotor SA gearmotor with encoder], as well as [[Actuators_Available_in_the_Mechatronics_Lab#Faulhaber_1524E006S_motor_with_141:1_gearhead_and_HES164A_magnetic_quadrature_encoder|the local wiki page]]<br />
* [[Adding a magnetic encoder to a GM3 Gearmotor]]<br />
** Using magnetic switches (Hall Effect)<br />
* [[High-current devices|Driving high-current devices: several options]]<br />
* [[Driving a Stepper Motor]]<br />
* [[Driving an RC Servo]]<br />
* [[Accelerometers]]<br />
* [[Strain gauges]]<br />
* [[Using the Basic Stamp Microcontroller|Basic Stamp Microcontroller]] <b>Not recommended for DC2008</b><br />
* [http://www.mech.northwestern.edu/courses/433/Writeups/Battery_NiMH/ NiMH rechargable batteries and chargers]<br />
<br />
<h3> [http://peshkin.mech.northwestern.edu/datasheets Prof. Peshkin's favorite datasheets]</h3><br />
<br><br />
<br />
<h3>PIC 18F4520 prototyping board </h3><br />
*[[4520 Board intro|Prototyping board intro]]<br />
*[[4520 Board construction|Assembling the 18F4520 prototyping board, circuit, parts]]<br />
*[[4520 Board use|Using the 18F4520 prototyping board]]<br />
<br><br />
<br />
<h3>Programming with CCS C </h3><br />
*[[C language|The C language]]<br />
*[[CCS C|CCS C, specifically for the 18F4520]]<br />
*[[Embedded Programming Tips for CCS C]]<br />
*[[CCS IDE|Using the CCS development environment]]<br />
*[[Debugging C on a PIC]]<br />
*[[More debugging tips]]<br />
*[http://www.ccsinfo.com/forum/ CCS user forum]<br />
<br><br />
<br />
<h3>Interfacing and skeleton code for the PIC 18F4520</h3><br><br />
<b>These topics have wiki pages <i>and</i> sample code available</b><br><br />
<b>[http://peshkin.mech.northwestern.edu/pic/code Link to all sample code here.]</b><br />
<br><br />
* [[Digital inputs & outputs]] (filename: DigitalIO)<br />
* [[Analog Input]] (filename: AnalogInput)<br />
** reading a trimpot<br />
** reading a phototransistor<br />
** amplified phototransistor, and IRED strobing<br />
** using an instrumentation amp (example: for a strain gauge)<br />
* [[Analog Output|Analog Output, and the I2C bus]] (filename: AnalogOutput)<br />
* [[Waveform Generation with AD9833]] (filename: AD9833)<br />
* [[SPI - Serial Peripheral Interface - on the PIC]]<br />
*[[Pulse width modulation|Pulse width modulation (PWM) for driving motors or other high current devices]] (filename: MotorPWM)<br />
** using H-bridges<br />
* [[Interrupts]]<br />
* [[Quadrature decoding in software]] (filename: QuadratureSoft)<br />
* [[Quadrature decoding in hardware, or just counters]] (filename: QuadratureHard)<br />
* [[Running RC servos]] (filename: RCservoSoft & RCservoHard)<br />
* [[Watchdog timer]] (filename: Watchdog)<br />
* [[PIC RS232|RS-232 serial communication between a PC and a PIC]] (filename: RS232)<br />
* [[C Example: Serial LCD|Text output to a serial LCD display]]<br />
* [[C Example: Parallel Interfacing with LCDs|Text output to a parallel LCD display]]<br />
* [[Servo skeleton with fast & slow interrupts]]<br />
* [[XBee radio communication between PICs]] (and between a PC and a PIC)<br />
* [[I2C communication between PICs]]<br />
* [[Serial communication with Matlab]]<br />
* [[SPI communication between PICs]] <b> (Note: this function has not been successfully tested)</b><br />
* [[Microphones]]<br />
* [[Ambient light color sensing]]<br />
* [[Controlling a seven segment display]]<br />
* [[Storing constant data in program memory]]<br />
* [[PIC computation time benchmarks]]<br />
* [[Stepper motor control with the PIC]]<br />
* [[Global Positioning System]]<br />
* [[IR communication between PICs]] <b> (Note: this function has not been successfully tested) </b><br />
* [[Interfacing to External EEPROM]]<br />
* [[I2C Motor Controller]]<br />
* [[Interfacing with a Photodiode Array]]<br />
<br />
<br><br />
<b>These topics have sample code available, but no wiki pages yet</b><br><br />
<b>[http://peshkin.mech.northwestern.edu/pic/code Link to all sample code here.]</b><br />
<br />
* Counter0 - Counting pulses with Timer0]<br />
* Counter1 - Counting pulses with Timer1]<br />
* Interrupt0 - Periodic servo cycles using interrupt routines, 10mS & slower; Timer 0]<br />
* Interrupt2 - Periodic servo cycles using interrupt routines; 10mS & faster; Timer 2]<br />
* InterruptExternal - Interrupts generated by an external pulse]<br />
<br />
<br><br />
<b>These topics need more development</b><br><br />
<b>[http://peshkin.mech.northwestern.edu/pic/code Link to all sample code here.]</b><br><br />
* AnalogOutputParallel - Analog output using 8 digital lines]<br />
* PIC-to-PIC communication <br />
* Zigbee radio communication<br />
* Modulated IR communication<br />
* Strobing LEDs or IREDs for better range and immunity to background light<br />
* I2C communication <br />
* CAN bus<br />
* Capturing data to Matlab<br />
* Running stepper motors<br />
<br><br />
<br />
<h3>PIC Microcontrollers</h3><br />
* [[PIC Microcontrollers with CCS Compiler]], for DC, 333, etc, using the CCS ICD-U40 device <b>[this section has been replaced by the material above]</b><br />
* [[PIC Microcontrollers with C18 Compiler]], for e-puck, or using the Microchip ICD device or<br />
<br><br />
<br />
<h3>e-puck Mobile Robot</h3><br />
* [[e-puck Mobile Robot]]<br />
<br><br />
<br />
<h3>[[Printing Circuit Boards]]</h3><br />
<br />
* [[PCB Artist | PCB Artist: Software provided by Advanced Circuits]]<br />
<br />
<h3> Electronics </h3><br />
* [http://hades.mech.northwestern.edu/wiki/index.php/Category:Electronics Electronics]<br />
* [[Phase-Sensitive Detection]]<br />
* [http://en.wikipedia.org/wiki/Operational_amplifier_applications Op-Amp Applications]<br />
<br><br />
<br />
<h3>Analog and Digital chips</h3><br />
* [[Comparators | Comparators: the analog to digital interface]]<br />
* [[Filtering with the LMF100 | Filtering with the LMF100]]<br />
* [http://en.wikipedia.org/wiki/Operational_amplifier_applications Opamps : building blocks of analog computation]<br />
* [http://www.mech.northwestern.edu/courses/433/Writeups/InstAmp/instamp.htm Instrumentation amps, and NU circuit board for them]<br />
* [[LED Drivers | Controlling large numbers of LEDs with LED drivers]]<br />
* [[Optoisolators | Signal transfer while electrically isolating circuits]]<br />
<br />
<br clear=all/><br />
<br />
<h3>[[:Category:Sensors|Sensors]]</h3><br />
<br />
* [[Potentiometers|Angle, Linear Position: Potentiometers]]<br />
* [[Optointerrupter|Beam Breaker: Optointerrupter]]<br />
* [[Optoreflector|Proximity: Optoreflector]]<br />
* [[Sensing optical tape|Infrared reflectivity : Sensing optical tape]]<br />
* [[Reed Switch|Proximity: Reed Switch]]<br />
* [[Hall Effect Sensor|Proximity, Angle: Hall Effect Sensor]]<br />
* [[Rotary Encoder|Angle: Rotary Encoder]]<br />
* Angular Velocity: Tachometer<br />
* [[Photodiodes and Phototransistors|Light: Photodiodes and Phototransistors]]<br />
* [[Photocell|Ambient Light: Photocell]]<br />
* [[Thermistor|Temperature: Thermistor]]<br />
* Temperature: Thermotransistor IC<br />
* Audio: [[Microphones]]<br />
* [[Accelerometers|Tilt, Acceleration: Accelerometers]]<br />
* [[Strain Gauge|Force: Strain Gauge]]<br />
* Current: Current Sense Resistor<br />
* [[Limit Switch|Contact: Microswitch (Limit Switch)]]<br />
* [[Ambient light color sensing]]<br />
* [[Global Positioning System]]<br />
* [[Optics]]<br />
* [[Optical Locating]]<br />
* [[Lateral-Effect Photodiode]]<br />
* [[IR Target Illumination|IRED's]]<br />
<br />
<br clear=all/><br />
<br />
<h3>[[:Category:Actuators|Actuators]]</h3><br />
[[image:All-actuators-captions-small.jpg|thumb|300px|[[Actuators Available in the Mechatronics Lab|Available Actuators]]|right]]<br />
<br />
* [[Brushed DC Motor Theory|Brushed DC Motors]]<br />
** [[Choosing a Motor and Gearing Combination|Choosing a Motor and Gearing Combination]]<br />
** [[Linear Amplifier Motor Driver|Driving Using a Linear Amplifier]]<br />
** [[Driving using a single MOSFET|Driving using a single MOSFET]]<br />
** [[Pulse Width Modulation|Driving Using Pulse Width Modulation]]<br />
** [[PIC PWM Motor Driver]]<br />
** [[Gear Motor]]<br />
** [[Pulse Width Modulation]]<br />
** [[Pulse_width_modulation]]<br />
** [[Driving using a single MOSFET | Driving a DC motor using a single MOSFET]]<br />
** [[Driving a DC Motor using PWM]]<br />
** [[Driving a high current DC Motor using an H-bridge]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/AddEncoderHobbyEngGearMotor Adding a rotation encoder to a gearmotor]<br />
** [[Using Opto-Isolators to Prevent Interference]]<br />
* [[Brushless DC Motors]]<br />
** [[Driving Brushless DC Motors]]<br />
* [[Stepper Motor Theory|Stepper Motors]]<br />
** [[Stepper Motor Circuits|Driving Stepper Motors]]<br />
** [[Unipolar Stepper Motor Driver Circuit]]<br />
** [[Bipolar Stepper Motor Driver Circuit]]<br />
* [[RC Servo Theory|RC Servos]]<br />
** [[555 Servo Circuit|Driving Your Servo Using a 555 Timer]]<br />
* [[Solenoid Theory|Solenoids]]<br />
** Practice: Driving Your Solenoid<br />
* AC Motors<br />
** [[Using the Yaskawa Motors]]<br />
* [[Fans As Actuators|Fans As Actuators]]<br />
* [[LIMS Air Hockey Table|LIMS Air Hockey Table]]<br />
* [[Actuators Available in the Mechatronics Lab]]<br />
<br clear=all/><br />
<br />
<h3>Mechanical Design</h3><br />
*Mechanics of Materials<br />
**Beam Mechanics<br />
**[[Mohr's Circle]]<br />
*Failure Theories<br />
**Static Loading<br />
**Variable Loading and Fatigue<br />
*Fastening<br />
**Nuts and Bolts<br />
**Keys and Keyways<br />
**Press-fits<br />
**Set Screws<br />
*Support<br />
**Housings<br />
**Shafts<br />
**[[Bearings]]<br />
*Transmission<br />
**Rigid: [[Gears]]<br />
**Flexible: Belts, Chains<br />
**Motion Connection/Separation: Clutches, Brakes, Couplings<br />
*Linkages<br />
**Serial Chains<br />
**Parallel and Closed-Loop Chains<br />
*Other: springs/dampers, cams, etc.<br />
<br />
<br clear=all/><br />
<br />
<h3>The PC/104 Stack</h3><br />
[[Image:Img0174.jpg|thumb|300px|[[PC104 Overview|The PC104 Stack]]|right]]<br />
* [[PC104 Overview|Overview]]<br />
* [[The PC/104 Lab Kit]]<br />
* Hardware:<br />
** [[Advantech CPU Card]]<br />
** [[Sensoray 526 Data Aquisition Card]]<br />
<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#power[Power Components]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#electrical[I/O Electronics: Analog I/O, Digital I/O, Encoder Connections]]<br />
* Advanced: Creating a Working Stack from Parts<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm [Building the Breakout Board]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#ribboncables[Breakout Board Ribbon Cables]]<br />
** [http://www.mech.northwestern.edu/courses/433/Writeups/PC104BoB/stack.htm#mechanical[Assembling the PC104 Stack]]<br />
** '''[[Creating an xPC Flash Boot Disk]]''' <- when new version of MATLAB<br />
* Custom Boards<br />
** Dual PWM Motor Controller<br />
** Dual Linear Amplifier Motor Controller<br />
<br clear=all/><br />
<br />
<h3>xPC Target Real-Time Operating System</h3><br />
<br />
* [[xPC Overview|Overview of Real-Time Programming with Simulink and xPC Target]]<br />
* [[Configuring xPC Target PC|Configuring xPC Host/Target PC]]<br />
* [[Creating a Simple xPC Program|'''Quickstart''':Creating a simple xPC Program]]<br />
* [[Common xPC Blocks|Commonly Used Blocks]]<br />
* [[Using the Host Scope]]<br />
*Advanced<br />
** Model Properties<br />
** [[XPC M-file Communication|M-file communication]]<br />
** Using outside of the lab<br />
** [[media:standalone.pdf|Standalone Mode]]<br />
** Stateflow<br />
* Code Examples<br />
** [[Controlling a DC Motor with an Encoder]]<br />
** Something With State Machine<br />
** [[Using RS-232 and Printing to LCD]]<br />
**[[UDP Communications between Target and Host PC]]<br />
** M-functions and S-functions<br />
** [[xPC Code From Student Projects]]<br />
<br clear=all/><br />
<br />
<h3>QNX Real-Time Operating System</h3><br />
*[[media:qnxtemplate.zip|QNX Control Program with Interrupts]]<br />
<br />
<br clear=all/><br />
<br />
<h3>Lab Supplies and Data Sheets</h3><br />
<br />
* [http://spreadsheets.google.com/pub?key=pa_bNAhFF-OvvxpSje1KDYg&output=html&gid=0&single=true Generally stocked lab inventory ]<br />
<br />
<br clear=all><br />
<br />
<h3>[[Vendors]]</h3><br />
<br />
<br clear=all><br />
<br />
<h3>Other Software</h3><br />
*[[List of Useful Software for Download]]<br />
*Circuit Schematics and PCB Layout<br />
*LaTex Document Preparation<br />
** [http://meta.wikimedia.org/wiki/Help:Formula Mathematical Formulae]<br />
** Document Formatting<br />
** [[LaTeX Software Setup|Software Setup]]<br />
** IEEE Styles<br />
<br />
<br clear=all><br />
<br />
<h3>[[Other Lab Equipment]]</h3><br />
* Prototyping Tools<br />
** [[Tektronix TDS220 Oscilloscope]]<br />
** [[Tektronix CFG253 Function Generator]]<br />
** [[media:Mastech_power_supply_manual.pdf|Mastech Power Supply]]<br />
** Fluke III Multimeter<br />
** Benchtop Multimeter<br />
** Powered Breadboard<br />
** Soldering Iron<br />
* [http://ediacaran.mech.northwestern.edu/neuromech/index.php/Lab_Equipment High Performance Neuromechatronics Benches]<br />
* The Sensoray 626 DAQ Card<br />
<br />
<br clear=all><br />
<br />
<h3>Course Material</h3><br />
* [[ME 224 Experimental Engineering]]<br />
* [http://lims.mech.northwestern.edu/~lynch/courses/ME333/2008/index.html ME 333 Introduction to Mechatronics]<br />
** [[Lab 5]]<br />
** [[Suggested final projects]]<br />
** [[ME 333 final projects]]<br />
<!--<br />
* [http://www.mech.northwestern.edu/hartmann/ME333_CourseInformation.html ME 333 Mechatronics]<br />
--><br />
* [http://www.mech.northwestern.edu/courses/433/ ME 433 Advanced Mechatronics] <br />
<br />
<br clear=all><br />
<br />
<h3>Miscellaneous</h3><br />
* [[Swarm Robot Project]]<br />
** [[Swarm Robot Project Links]]<br />
<br />
* [[Indoor Localization System]]<br />
* [[Robot Helicopter Project]]<br />
* [[E-Puck Color Sensing Project]]<br />
* [[Guitar Tunning Project]]</div>MattT