Tips for Design Challenge

Things you should know about the Design Challenge

1. You have 3 tries to complete the track
2. The first hour of the Design Challenge is for last minute changes to your circuit, preparation of your car, and charging of 2 batteries
3. Only 4 sensor bars & 10 sensors can be used
4. If you don't do well on the Design Challenge, it's strongly suggested that you compete in the contest (rules on pg 15 in lab manual)

Tips for Design Challenge

1. Find the right sensor bar height. This is crucial. In the past, groups did poorly and the only problem was due to the sensor height.
2. Make sure all connections are solid. Be sure you're not pinching the wire insulation.
3. Think about how many speeds you need for speed control. Do you need 4-bit resolution?
4. Use the oscilloscope to debug your circuits. Make sure you are getting the logic levels that you expected
5. Always have a circuit diagram. It helps us (TAs) understand and debug your circuit in a shorter amount of time. Also, it's better to eliminate most, if not all, wire loops on your protoboard. It's easy for the TAs to understand & check your circuit.
6. Measure V1 and V2 on your protoboard, if your circuit suddenly doesn't work
7. If you're using the PWM, you may need to slow down the oscillator by replacing the capacitor on the PWM module
8. If you're using sequential logic, beware that the circuit can become unstable and unpredictable
9. Think about if you should use the modified NAND/NOR gates (Experiment #6)
10. Figure out which current amplifier setup you will use to drive the motors, either Circuit A (motor at emitter of CA), Circuit B (motor at collector of CA), or CAB module.

Questions You Should Know the Answers to for Getting Full Marks for Design Challenge

1. What's the "best" sensor height?
2. What's your final sensor placement?
3. How are you approaching turns? Are you slowing down to take turns or going full speed and compensate for overshooting the turn?
4. Can I complete 3 consecutive right turns reliably?
5. What's my car algorithm/strategy? Hug or Follow or Remember the tape?
6. How many speeds do I need? Do I want to go in reverse?
7. Does my car get stuck on the track? How do I fix this?