Added complexities. Classic amateur robot stuff I would guess.

1. The sonar proximity detectors have a fairly wide field of "vision". If the car bumps against the side wall at a sharpish angle, the front detectors see the wall. The program thinks the car has come to a corner in the room and makes a maximum sharp left turn. This sets the car up for a very zigzag pattern.

I tried making a "megaphone" for the front sonar pingers out of the cardboard tube on a toilet paper roll. The sonar "detected" the tube. Hmmmm

2. When the battery begins to fade the car has a difficult time moving from a dead stop. Given a nudge, it takes off. The net behavior becomes quite different. Discombobulating to say the least.

3. The wheels and the steering servo still appear to be reacting too slowly. Exactly what is the problem is not clear.

That is the report for today...

Ken