This robot is build using small stepper motors that are actually used within the dashboard of VolksWagen cars. I bought them at http://www.didel.com , where you can find a lot of other interesting robot stuff. They don't generate a lot of torque, but seem to be sufficient to drive a small autonomius vehicle. An other plus is the low power consumption, a simple 9V battery can drive the system for more then a full day.
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