Circuit Schematic

To enable the RL agent to control and monitor the system, the circuit must include both control of the panels servo motors as well as feedback on the power generated by the solar panel / power consumed by the motors during operation. Starting with one panel to prove out the concept, the below circuit schematic captures the key features of the system.

The circuit and Arduino are powered by a 9V battery
The voltage from the power source is regulated with an L7805 regulator to bring it down to 5V for use by the components
Two SG90 servo motors are needed to control one dual-axis tracking panel. They get their power from the battery but their PWM to adjust position is controlled by two PWM pins on the Arduino board
To measure power output from the solar panel, an Adafruit INA260 is used to measure voltage, current, and power in real time. This is transmitted to the Arduino board via I2C protocol

Circuit Validation

To validate each of the components of the circuit before integrating the actual solar panel and 3D-printed housing, I used a 12V power supply and fluctuated voltage to validate measurement of power along with motor control. Below is a picture of the circuit in operation, with each of the components above called out.

With the circuit fully functional, I am able to move on to final integration with the 3D-printed housing and actual solar panels.

Important Advice if You’re Building This

If you’re building your own version of this project, there was one snag I hit during circuit testing: the INA260 device needs to be soldered to be breadboard pins, or else the Arduino won’t be able to create a stable connection to the device.

For integrating and testing the INA260, I found this page very valuable:

Soldering guide: https://learn.adafruit.com/adafruit-ina260-current-voltage-power-sensor-breakout/assembly
Arduino communication: https://learn.adafruit.com/adafruit-ina260-current-voltage-power-sensor-breakout/arduino

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