Northwestern Design Competition

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.
• Goal:
  • 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

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