Hi Ken,

I think either the "seek the light" or the "keep the wall on your side" technique would be fine for your purpose.

The "stay close to the wall" method is probably more versatile because it could work in any room with walls...
The "seek the light" method sounds a little cheaper and easier to implement (just a gut feeling). Just point a bunch of CDS cells around the perimeter of the car, read the values into your ADC channels and look for the one with the lowest resistance. If the lowest resistance one ISN'T at the front of the car then you need to correct the steering until is.

With the light method, you'll need to regain control before the car actually GETS to the light, or have a way to make sure it passes to one side so the car doesn't dive straight into the heart of the sun...



steve