I too initially designed with two battery packs. One for the servos and the other for the electronics. My problem is one of packaging. Getting a cheap kit that fits easily into a HPI Racing Touring Car Ready to Race package is way beyond my expertise. Why the HPI car? That is what I have. Also Ten80 Education

( Which I know as http://www.ten80eduction.com)

specializes in using radio control cars for curriculum and lesson plans supporting STEM in our schools. One of that company's sponsors is HPI Racing. I hope to get ten80 support. One battery is much easier to mount than two.

I took my car again for a run. It is using the "there is nothing within four feet of me, I must be under radio control" toggling algorithm. I liked the effect. It is important that the room have lots of room. Clearly a gymnasium fits that criteria. Adding the photoresistor system is more than I can deal with at this time.

Two projects are looming. 1. Get help and advice on packaging (surface mount prototyping). 2. Create a video story board then shoot a video showing what I have built, why I built it, how to modify the code and why I think middle school students will jump to learn.

I discovered a neat trick today. The studio has a small push cart with roller skate sized wheels. I put my car on the cart (back end facing me - it has no sonar sensor) and pushed it around the maze. I could easily see the reaction of the car to each position. It made very clear that the problems are speed, momentum and reaction time.

Ken