Here are some images of the completed object. It is a little bulkier than I originally intended, mainly to accommodate the 4 AA batteries. My original idea of powering the whole circuit using a coin cell battery did not fly because it does not supply enough current.
The base is made out of a thin custom cut piece of wood. The shell is a plastic dome covered with some fur I got from skinning a teddy bear. The dome offers good protection for the electronics on the top of the base, but I still need to find a way to guard the motor and batteries at the bottom.
 
 
I took DizzyCat up to Montreal with me to test it out with my cat before working on the collar. I was a little worried that she would not be too crazy about it since it is a little slow and noisy. As can be seen in the following video, I was right to worry. Back to the drawing board…
Been there. Cats are excruciatingly difficult to make them go nuts over technology. I built a BEAM robot for my private slice of hell this summer, spending a good couple of days figuring stuff out and tweaking its avoidance behaviors to act just like a “real” mouse/bug/other small edible animal.
Then came the big moment. I put the bug in front of the cat, armed it, tapped its “attack” sensor to trigger the avoidance behavior and it started moving. Right at the cat. You know what she did? Just raised her paws in sequence so that the robot just rolled under her without even touching her. That was all the attention the machine’s ever gotten from that cat.
We call it the Electrobug: http://picasaweb.google.com/sekerama/GISFCH