I know it’s not much, but the new version is ready for coding. It knows how far it is from obstacles (in front), it steers, it goes forward and backward. And it does it all in python. Code and current SVGs on Github any day now.
Almost all of the parts are laser-cut (I stole the front wheels and axle from a copy of the earlier 3D-printed version. Cutting time on a Glowforge is about 10 minutes.