I wanted to make a robot from scratch rather than buy a kit so I ended up making one using some random stepper motors I got out of two salvaged panasonic dot matrix printers. It took a little bit of experimentation to figure out the wiring to the individual coils so I could interface them with the arduino. I tackled this project with no specific design in mind other than I had the two motors. I cut all the acrylic on a cnc router and had to make some shims after changing my design for the rear wheel. Eventually I added a small linear motion slide to the front to incorporate a grabber… These are all the pictures I could find, including one from drawing its first circle while I was calibrating it. I also improvised the wheels using o-rings and more machined acrylic that I screwed into the original gear on the motors.