I was trying to build my own scantron grader for my students’ final exams

It turns out OCR is so good these days that it’s easier to build an auto grader that detects hand written answers instead of detecting shaded in bubbles

You can recycle your number 2 plastics at home using a panini press or George Forman grill

It’s not pretty, but I made my own fenders for my bike using plastic milk cartons

tore it apart and ignored all the built in sensors, just grabbed the red and black lines for the 4 motors

4 motors into 2 l298n controllers into a raspberry pi pico running a tcp server

iPhone app uses game controller and connects wirelessly to the pico

16v battery pack from 4 18650 cells

Upgraded my roomba