Well I started my chassis last weekend, I'm assembling motors and other
stuff.

I'm looking at National's LMD18200 motor driver IC - looks simple to use and
foolproof (an important feature! ;)  )

The PIC's tasks will be pretty straightforward.  I've got a program mapped
out in my head already.

I'm thinking of putting the mower blades both under PIC control and a manual
switch.  That way I can turn off the mower if I'm letting the thing bounce
around in a demonstration for onlookers.

I suppose the PIC could handle input from a tipover sensor.  How abaout
battery management though?

I guess I'm looking for a chip or chips that can handle:

1. Charging a NiCad from a solar cell   (There's another Post on this
today - I'll look for it)

2. Telling the PIC that the battery is low and needs charging. The PIC then
stops mowing and moving, and waits for more juice to arrive via the sun.

3. Preventing overvoltage from teh solar cell from damaging the NiCad