FIGURE 2. A typical Micromouse maze in 2010.
Quester’s features:
• Differential steering with quadrature shaft encoders on
each wheel. Buckley cut a set of evenly spaced holes in
the output gears and used sets of mini LEDs and
phototransistor receptors for the wheel encoders. (Note:
Many early Micromice started out with Ackermann or
‘car-type’ steering but found turning corners very
difficult).
What would David have imagined that the next step
might have been when he was back in 1981? As he stated
in February’s comments on the SRS list server: “Today’s
control computers are much more powerful and a heck of a
lot easier to use, but the software ideas for small robots
haven’t moved on. My robots now have a multilevel
behavioral operating system (BOS) with reactive subsystems
for survival and human interaction, sequence subsystems so
they can be given lists of things to do, and deliberating
subsystems so they can sort out internal conflicts. Above all,
they accept high level commands so I don’t have to keep
editing the program.”
The Next Step In Robotics
FIGURE 3. A quarter scale Bee Micromouse robot from Japan.
Micromice of Today
Micromice — as well as almost all personal,
experimental, and hobby robots — have changed quite a bit
in the past three decades. The 1/4 scale Bee shown in
Figure 3 from robots-dreams.com is probably the next
few steps beyond Quester and is not at all typical of most
micromice in today’s contests. The dramatic reduction in
size over the years illustrates the many next steps that
competitors have used in construction of their robots.
The Bee’s Specs and Components
Check out these top features:
• The Bee’s top speed: Two meters a second or 6’ 7”/sec
— really fast.
Japan has been very supportive of Micromouse
contests for over 27 years. The Bee and another half-size
mouse shown in Figure 4 made by RT Corporation in Japan
are typical of these smaller competitors. As you can see, the
Bee is a very tiny robot and is a quite capable competitor
with speeds of a real mouse scurrying away from a hungry
cat. The larger — but still tiny half-size mouse next to a nine
volt battery — appears to be about a two inch cube. The
larger AIRAT- 2 shown in Figure 5 from the Hong Kong-based Robot Store is another more typical Micromouse
robot. It uses an 8051 (remember those?) CPU on a
JS8051-A2 processor board, and appears well crafted with
nicely machined wheels and an LCD readout on the CPU
board. It’s well laid out and costs $650.
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