This week, I presented the final presentation for the group. Additionally, I created the circuit that should be our final motor control circuit for the DC pumps on the Rover Upper Deck. This took a few tries:
For some reason (which I still cannot figure out), the motor driver on the upper deck would not output the desired nominal battery voltage on the motor output, despite the enable pin being set to high on the Raspberry Pi. To try and mitigate this, I attempted to hold the pin at 5V (necessary because the Raspberry Pi uses 3.3V signaling) and activate the pumps. They were still not receiving the voltage required when connected, which is something for which I still do not know the reason- my current speculation is max power on the board.
Eventually, I decided to implement a logic level shifter circuit to work with the motors. It is a simple power transistor circuit, attached to a logic level shifter. Testing it with raw voltage, it works, but I’m about to test to see if it works with motors (If it does, it’ll be on the final Rover.) A picture (we’re currently out of space, I’ll endeavor to fix that soon):
https://drive.google.com/file/d/1S7TOr7209yDcjg8nRn55qBP8nFoxBLN4/view?usp=drive_link
Progress is on schedule with the TechSpark demo in mind, though I will work on the ML side of things in the following days. I would like to finish the entire robot suite by next week.