The biggest change… the motor mounts. Using a laser cutter, at the TechShop, the whole assembly is now built into the plexiglass chassis. The motors simply zip tie onto the chassis through the precisely cut/aligned mounting holes (easy to reproduce, fast to mount, and no alignment issues). FYI: all the wheels and motors are not mounted on the robot since they need some pre-assembly prep and I didn’t what to have to cut them back off.

The plexi tiers mounted on top of the chassis are stand-ins for the circuit boards. The front and rear tiers will hold the ultrasonic sensors, the middle tier will hold the motor controllers, gyro, and accelerometer it also has a cutout to accommodate a 9v battery to power the micros and sensors, and the top level will hold the master micro controller, voltage regulator, switches and connectors.

TR-1 Chassis
(bot 118×80mm - maze cell 168×168mm) It has enough room to turn in place in a single cell but since it bidirectional it won’t have to. It is about 12mm shorter and 12mm wider than the Japanese version (26th All Japan MicroMouse Contest) so its diagonal clearance is about the same. The best I could do on width is about 75mm because of the motors and then I would have to change the battery configuration.

The inside diameter of the wheels was turned out a few thousandths and the gear heads were hand filed down to fit inside the wheel (it bought me a total of 2cm less in width) and cost me a day of time.

The motor mounts are still a pain in my ass (creation/alignment/positioning) Since they are hand bent it is difficult to get them the same. Any suggestions? They are 2-1/8 long by 5/8 wide sheet aluminum with 5/16 tabs on each end bent around a wooden dowel form I created. I was just thinking of zip tying the motors to the inside face of a piece of angle aluminum (1 piece holding the two motors on each end).

Micro mouse test maze wall and post creation. These are some test maze components (200 walls, 160 posts… not quite a full maze but a good test environment). The pieces are made out of half inch MDF and were created at the Sawdust Shop in Sunnyvale.

Full competition maze at UC Davis Picnic Day April 19, 2008