The MMR4 v1.0


This micromouse is currently under construction. Here an hour, there an hour. Someday, maybe it'll be finished.

Given my lack of a fancy machine shop, one of the design principles is to keep it mechanically simple. Hand tools. Solder. Glue.

The other guiding design principle, is laziness. Off the shelf parts where possible.


This mouse is a basic "wheelchair" design. Two large stepper motors. Side facing optical sensors.

Tech Specs

motors Oriental Motors Vexta PK243 Steppers
batteries 2 x Canon BP-511 (Li-ion 7.4V, 1.1Ah)
CPU AMD Elan SC520 (486 class)
sensors 6 x Sharp GP2D120
OS a stripped down NetBSD
storage 8MB CompactFlash
size chassis: 5 x 2.75 x 2 in, wheels: 2.5 in
ckt board 3 x 5 in, 4 layer

Tech Notes

CPU Choice

These days, it seems like everyone else is trying to build mice out of PIC chips and Z80s. So silly.

The burn an eprom, carry it across the room, test the code, oops, try again, process... Too tedious. The ability to compile, test and debug code on my "normal" computer using familiar tools--much easier, much better.