smallest motion sensitive turtle style robot?

Have you thought about adapting one of those micro RC controlled cars with an AC-coupled CdS cell triggering a 555 that runs the motor for a few seconds when the cat's shadow falls over it?

The problem with 2" or less is that you don't have much room for batteries...

Of course, you could just buy a basket of mice ;)

Hi "Mad Scientist Jr",

Not quite 2"x2", but you want:

My cat's love it... It's featured in the book:

We built a bunch of these as a club build project day. With brand new components (motors, switches, etc.), they maxed out at $20 CDN ea.

HTH Steve

I was in Target the other day and saw a 'mouse' body that was on top of one of these micro rc cars that charge in 45 seconds. IIRC, it will fit in the

2x2 you wanted. However it would have to be modified to be autonomous. It was in the pet department.

Mark