Back in the late 20th Century, the micromouse contest we new and all sorts of designs were tried. Moderm micromouse designs have tended to converge but Derek and Jim, for their first half-size micromouse decided to made a new, and tiny, version of a classic – Thumper.
Thumper had two particularly interesting design features. One was the use of four drive wheels. They were arranged so that the robot could move in any orthogonal direction without having to actually turn around. Another feature was the inclusion of a voice synthesizer for direct, spoken feedback. Sensing of the walls was done from above and, to keep out the ambient light, there was a huge shield that covered a maze cell and the surrounding walls. The shield looked suspiciously like the lid of a biscuit tin and was about 25cm square. On top of that was a collection of circuit boards for the processor and control electronics.
Now, of course, the contest has moved towards half-size mazes and robots. The maze cells are only 84mmx84mm internally. Given the size constraints, it is all the more remarkable that Derek and Jim have managed to make a tiny micromouse that uses four drive motors and four servos to replicate, and improve on, the capability of Thumper. All that, the sensors and the processor – an Arduino Nano – fit inside the half-size maze cell. To top it all off, literally, they have a fifth servo that controls and rotating head unit for further entertainment value.
The speech synthesizer? Yes, they have that too although now, of course, it can play any audio file from a micro SD card.
In this month’s UKMARS presentation, Derek describes the background, design and operation of his remarkable little micromuse.