Maddy Bot remote control or auto avoid robot vehicle

Originally I built another robot vehicle using motors from a clock that spins around madly, a mobile phone holder an Arduino and motorshield with Bluetooth. Which could be remote controlled via a number pad using a Nano also with Bluetooth. Then I picked up this 80's BigTrack toy from a boot sale for a pound(£1), with visions on uses for it in projects that I've made or experimented with. So it's big, plenty of space to add extra stuff to!

Maddy's brains

the layout so far

The Arduino Nano remote control

The Windows phone app in development