Work in Progress. Not ready yet.
Grading
This is a graded exercise. You will need to demonstrate it to your tutor during Tutorial 3 (Week 6/7).
Task
Create a program such that the rotation speed and direction of a motor is dependent on the distance from an obstacle as given in the table below. The motor has to be powered using a separate battery, and not from Arduino (Arduino only controls the motor, does not power it).
| Distance from Obstacle | Motor Rotation |
|---|---|
| Distance > 50 cm | Clockwise, full-speed |
| 35 < Distance <= 50 cm | Clockwise, quarter-speed |
| 30 < Distance <= 35 cm | No rotation |
| 20 < Distance <= 30 cm | Anticlockwise, quarter-speed |
| Distance <= 20 cm | Anticlockwise, full-speed |
Hints
- Combine the codes and circuits in Ultrasonic Distance Sensor and DC Motors, and use multiple if conditions. You will need ifs to be nested, i.e., ifs within ifs.
- analogWrite() with values 255,0 (dir1speed,dir2speed) and 64,0 respectively can be used for full-speed and quarter-speed clockwise rotation. 0,255 and 0,64 can be used for full-speed and quarter-speed anticlockwise rotation respectively. The speed is not perfectly linearly related to the value (duty cycle) in practice, and that is ok for this exercise.