Alrighty, forging a head now.
Going to have to upgrade my arduino, i need more PWM output solutions on the board:
http://cgi.ebay.com/Arduino-Mega-ATmega ... 255b0ba223
so this is the I/O list:
1 Range Sensor - Analog Input, 0 to 2.55v
2 POTS, 4 leads total - analog input, 0 to 5v
3 LEDs - Digital Output, standard
2 VSS pins - Digital PWM output
1 enable pin per motor, 4 motors, 4 Digital PWM output
2 input pin per motor, 4 motors, 8 Digital PWM output
2 motors to drive the unit, 2 servos to give 2 degrees of freedom for the forward looking eye.
Will consider placing a IR emitter and reciever on the back to alert to obstacles behind the unit.
End tally of input output:
5 analog input
3 digital out
14 PWM output (exact limit of the board, incidentally)
This leaves me with approx 40 digital pins and 10 analog input pins to play with. i'm thinking the lcd screen and maybe a blue tooth module to communicate with a pc.