Northwestern Design Competition

DC2012

Scale arena:

Dimensions of the arena for 2012

Equipment

• NU32, USB cable, 6V power supply
• 2 drive motors, 2 motor mounts, 2 wheels
• large and small RC servos
• red and IR lasers
• 12"x24"x0.118" clear acrylic sheets
• AA batteries and packs

Workshop 1, Wednesday 1/18 5:30-7pm Tech L221, makeup Thursday 1/19 9-11am Mechatronics Lab

• How to program in MPLABX
• How to use the bootloader to put code on the NU32
• Digital output I/O (read a button and flash an LED)
• Analog input
• PWM output
• Sample code: Sample code for Workshop 1

Milestone 1, due by 1/27

• If a pushbutton is pressed, read the value of a potentiometer and change the brightness of an LED to the corresponding value with PWM

Workshop 2, Thursday 2/9 6-7pm Tech L221, makeup Friday 2/10 9-11am Mechatronics Lab

• Optical isolation for motors and RC servos
• Powering a motor with an h-bridge
• Writing to the 16x2 character LCD
• Laser detection of retroreflective tape / Optical line detection
• 2 1/2D design

Milestone 2, Due week of Feb 27

• Optically isolate a motor
• Read a potentiometer and write its voltage to the LCD
• Control the motor velocity based on the potentiometer reading
• Control an RC servo
• Detect a 3/4" wide black line on white paper with a phototransistor and LED

Laser cutting Workshop, Week of Apr 2

• Laser cutting
• 2.5D design
• Making a chassis, mounting motors and sensors

Chassis Milestone, Due Apr 13

• Demonstrate a robot chassis that can drive around the arena, bonus points for following a line, detecting and moving towards the moving goals, and detecting and moving towards a crate

Midterm Milestone, Due Apr 30 / May 1 / May 2

• Demonstrate some strategy - from the starting position, go get a crate and bring to back towards the goal

Pre-competition Milestone, Due May 9

• Demonstrate some advanced strategy - score several points

Competition May 19!

DC2011

Milestone 1

• On a button press, read the value of a potentiometer and change the brightness of an LED accordingly using PWM. Note: Do not use an h-bridge or motor as previously assigned.
• Due before Workshop 2 on Wed, 2/9.
• Sample code from Workshop 1

Milestone 2

• Due before Workshop 3 on Wed, 2/23.
• Goals:
  • Use code from NU32v2: Nokia 5110 LCD and NU32v2: Analog Input to read a potentiometer and print the voltage to the Nokia 5110
  • Optically isolate a motor and control its velocity based on the potentiometer reading
  • Do 1 of the following:
    • Mount a phototransistor to a laser and detect a cake OR
    • Detect a line of electrical tape on white paper with an optoreflector
• Datasheets
  • HBridge_L293D.pdf - H-bridge for driving a DC motor
  • Optocoupler_A847.pdf - Optocoupler to optically isolate your H-bridge
  • HexInverter_74HC04.pdf - Inverting chip to digitize optocoupler output
  • Optoreflector_OPB740.pdf - Optoreflector to detect lines or color
  • Optoreflector_QRE1113.pdf - Optoreflector to detect lines or color
  • Phototransistor_SFH310.pdf - Phototransistor to detect lines, color, or laser reflections
• Notes
  • DC2011_WS2_OpticalIsolation.pdf - How to optically isolate an h-bridge and servo motor using the A847 and 74HC04
  • DC2011_WS2_OpticalSensors.pdf - How to use the SFH310 to detect a cake and use the OPB740 or QRE1113 for line following
  • DC2011_WS2_Code.zip - Example code for the NU32v2 that will:
    • Control a DC motor hooked up to an optically isolated h-bridge, and control an optically isolated RC servo motor
    • Respond to serial commands to control the motors, write to the Nokia 5110, and read two analog signals

Milestone 4

• Due before Wed, 3/16
• Finish laser training, at least one person per team
• Construct a prototype chassis for your robot
• Do one of the following:
  • Follow part of the line on the 36" x 96" printout of this pdf
  • Detect a cake somewhere on the floor and drive to it

Breakout Boards

• Image of the breakout boards
• Circuit schematic of the breakout boards
• This board contains:
  • A spot to plug in the NU32v2 with some prototyping area
  • The optical isolation circuit with some prototyping area, the same size as the NU32v2 breakout board so it can be stacked on top
  • 8 SFH310 with LED breakout boards
  • 4 SFH310 with laser diode breakout boards
  • 1 LIS352AX accelerometer breakout board
  • 1 LSM303DHL tilt-compensated compass breakout board
  • 1 LPY550AL gyroscope breakout board
  • 1 LS7366R encoder decoder breakout board
  • 1 TCS3103 color sensor breakout board
• How to use the boards:
  • 

    Solder female header pins to the NU32v2 Breakout Board so that you can plug in and remove your NU32v2
  • 

    Solder sockets to the Optically Isolated Motor Board so you can remove burnt out chips
  • 

    The LED and Laser Phototransistor breakout boards will make it easier to attach wires to the sensors
  • 

    You can stack the NU32v2 breakout board with the Optically Isolated board

Brochure for 2011

• Brochure for 2011

Previous Years

Wiki pages on sensors, actuators, programming, and microcontrollers: use pages below

• Parts in the DC2008 quick start pack
• PIC C intro slides, as presented 2008/01/24 (pdf)
• PIC interfacing slides, as presented 2008/01/28 (pdf)
• Link to all sample PIC code here.

Sensors and actuators for DC

• Solderless Breadboard & wiring that works
• Using LEDs & IREDs
• Using a laser
• Infrared reflectivity
  • Using phototransistors
  • Sensing optical tape
• Comparators : the analog digital interface
• Faulhaber MiniMotor SA gearmotor with encoder, as well as the local wiki page
• Adding a magnetic encoder to a GM3 Gearmotor
  • Using magnetic switches (Hall Effect)
• Driving high-current devices: several options
• Driving a Stepper Motor
• Driving an RC Servo
• Accelerometers
• Strain gauges
• Basic Stamp Microcontroller Not recommended for DC2008
• NiMH rechargable batteries and chargers