Ultra low cost laser cut cardboard robot for DC motor.
I've been thinking about the lowest possible cost robot, and I have a good sized bag of DC motors which are not gearmotors, so I started thinking about how to drive a cardboard bot with those. I've seen pretty successful bots use the "motor shaft rubbing on the edge of a rubber wheel" trick so I thought about making a cardboard wheel into a rubber wheel with a fat rubber band stretched around the rim.
That needs a very smooth, very regular cutout wheel (more so than what the average person can do by hand) but then I realized, there are laser cutters, right? So no worries!
And that lead me to a few hours of fun this weekend in my preferred CAD system: OpenSCAD. Which culminated in publishing this "Thing" which anyone can now use to make custom DXF files that should align perfectly, given correct input values. It's a first pass, and probably has issues, but I hope someone will be interested enough to try it out and provide some feedback to improve it.
A good motor / controller / firmware package for a robot like this can be found here:
https://github.com/jmalins/BattleBot-...
TODO: Cut one and see how it works, adjust, iterate. Especially the crease parameter to see if it can be turned into a score rather than a cut.
TODO: Add a pattern of slots or holes to the wheel to support detection of wheel movement for feedback to the controller, allowing precise movement... a low resolution servo encoder.