Light-Tracking Device

In Mechatronics our final project was to design a light-sensing arm that could track the motion of light, much like a sunflower tracks the movement of the Sun during the day.

This was accomplished with:

2 light-dependent resistors (LDRs), 30° apart
Differential amplifier circuit, with the two inputs fed by the LDRs
PI controller

We used the differential between the two resistors to determine the direction to operate the motor. We finished the semester with a prototype suing 2 LDRs, but a version with more resistors could track more accurately and without as much wobbling.