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Some notes on an Evil Robot

I built a small robot to chase cats. Technically, this was not a robot since it was not autonomous, but rather a telepresence device. For a real robot see the one built by my friend Chris Jang.

The platform utilized a small video transmitter (cost $200) and a tricycle system with two powered wheels. The third wheel was a free castor. Each wheel was powered by a servo that was modified to spin freely (disconnect the feedback potentiometer).

The main problems encountered were:

   * Poor video quality
   * Poor video transmission range
   * Unable to right itself after being pushed over by feline foe.

The main advantages of the robot:

   * Small size
   * Maneuverability -- fine, precise control
   * Stability
   * Multiple terrain capability. This robot could handle soil, deep carpet, and linoleum very well.
   * Modular and easy to repair. Most components were attached with nylon cable ties. This made field repairs quick and easy.
   * Cheap

Things learned:

A slow robot using low geared motors is much better than a high speed robot. A "burst speed" mode for long straight runs would be a good improvement.

Video -- Video of a test run of the robot in action. This is an 8MB AVI file.

Photos of the platform without the video camera. I call this construction technique "field expedient". Some call it "crappy".

robot img1.jpg

robot img2.jpg

robot img3.jpg

robot img4.jpg