October has been a tough month for us. After rebuilding the robot in plywood (much easier to work with than acrylic) and putting in some motors with more torque, we were ready to test again.
The motors we tried were, again, micro metal motors from pimoroni - but 298:1 gear ratio instead of 50:1. It went forward - and backwards - but again, even with the extra torque refused to turn well. It was better - we could get it to turn if we put on some less grippy wheels - or were moving at the time. But not great. The large, soft, wide wheels we want to use (to give us some natural suspension over obstacles) just have too much grip.