|home >||Teal < MM1 > Quester||13 May 2021|
|MM1 - by David Buckley||1980|
In 1980 Dr John Billingsley introduced a UK version of the Micromouse competition, a simpler version of which was first held in 1978 in the USA.
The finals were in September at EuroMicro80 and after watching the competition I thought that a group should be formed at the North London Hobby Computer Club to build a Micromouse.
We formed a Micromouse group and discussed how to do it but it seemed nobody had any workable ideas so I built MM1 a chassis with motors and sensors and at about the start of November took it along to the Group at the Club. As soon as I showed it and was asked "where did you buy it" I knew the group was in trouble.
I then had to leave for a holiday in California, when I got back it was the Christmas holidays so the Polytechnic of N. London and the Club were shut. In the New Year when the Club reopened non of the Micromouse Group were still interested in making a Micromouse.
I had hoped that as I didn't know enough to build a microprocessor based controller that would fit in the samll space I had allocated on MM1 there would be somebody in the Group who could.
Since there was no longer any Group MM1 was put in the cupboard and I bought an Acorn System-1, a samll computer with hex keyboard and 7-segment display, and started work on a bigger Micromouse - Quester.
In April 2021, during continued Corona 'virus' lockdown I took MM1 out of the cupboard and checked it over, everthing seemed to work, the H-bridges drove the motors and the bump-sensors and IR-wall-sensors gave readings on a multimeter, so I polished up the bump-sensor wires, re-ironed the Solarfilm covering where it had bubbled and took some photos.
Putting a microcontroller on the top board will now be easy, so would the sensors have been enough to navigate a maze? - Another project!
The H-bridges are AC187 and AC188 pairs with BC177A input transistors.
The tyres are 'O' rings on wooden disc wheels and the motor shafts run as friction drives on the tyres, the weight of the robot keeps the shafts pressing on the tyres.
The bump-sensors are push to break the contact between the thin phosphor-bronze hanging wires and the tinned-copper 'U', sensitive with lots of travel.
The right and left front and side wall-sensors are IR emitters with phototransistor receivers, sensitivity can be set by the 1M ohm skeleton pots.