Electrical Power System Schematic

For each wiring diagram, red wires, black wires, magenta, and green wires indicate positive voltage, ground, digital signals, and analog signals, respectively. 

The following schematic shows the wiring connections of the MCU, analog multiplexer, and light sensors. For a light sensor to operate, the Vin pin must be connected to a 3.3 V lane provided by the MCU, the GND pin must be connected to a GND lane, and the S pin must be connected to one of the analog pins of the MCU. 

For a stepper motor to operate, each pair of phases must be connected to the corresponding A and B pin pairs. For example, Pins 3 and 4 would be connected to A1 and A2. For the motor driver to function, a power supply must provide voltage to the Vmot and GND pins; a 12 V power supply was used. Next, the STEP and DIR pins were connected to two available digital pins. The STEP and DIR pins relay the stepper motor's current step and rotation direction. A jumper connects the RESET and SLEEP pins because they were not used. Lastly, GND was connected to GND, and FAULT is connected to the 5 V MCU pin to provide power.

The following schematics shows the final design of the EPS. The schematic shows the connections of the solar panels, INA 219 current and voltage sensors, TEMT6000 light sensors, AS5600 magnetic encoders, PCA9548A digital multiplexers, CD74HC4067 analog multiplexer, Arduino IoT 33 MCU, motors, motor drivers, and power supplies. Capacitors were used for filtering, noise reduction, and voltage stabilization. Pull-up resistors were used to ensure the SCL and SDA provide reliable I2C communication.