Our Lab team was responsible for designing and constructing a mechanism that rotates a solar panel towards the highest light intensity.
I coded the entire Arduino program, which had to read in analog input from the potentiometer, & voltage changes from the photoresistor. It also had to output and control both a stepper motor and a DC motor.
By translating the changes in resistance of the photoresistor, and recording them across a 180° sweep in 10° increments, I could find the highest relative light intensity. I used the stepper motor to control the photo sensor. Then I would command the DC motor to turn to the correct position by live-reading input from the potentiometer, creating a closed-loop control system, albeit a basic one. The system had a ±10° precision.
We were only given a few instructions and just 6 components we were allowed to use. These were:
- 5V stepper motor
- 5V DC motor
- 2″x2″ photovoltaic Cell
- 180° rotary potentiometer
- Photoresistor
- Arduino Uno & Motorshield