I am using Arduino and Ardumoto dc motor controller to drive a DC motor. I am kind of at lost because i have gone through 10 different motors. They either don't work( not enough power ) or not powerful enough to drive the robot. Can anyone tell me, max voltage and amps provided to the motors AFAIK power to the motors are supplied through VIN pin? and are there any way to supply my own power and still use ardumoto to control the dc motor?
You could drive the motors with a separate power supply, then you can use a Darlington pair NPN transistor on the Arduino output pin, when the output switches on, the transistor supplies the necessary power to the motors.
If your wanting to use a single power supply, you could have a more suitable ac/dc PSU for the motors, then you can get a dc/dc converter to lower the voltage for powering your Arduino.
Refer to the data sheet. 50V max at 2 amp (or anything less) This is like 100 watts. The board (chip) should have its own power supply capable of whatever voltage your motor needs at 2 amp (per channel I think or 4 amp total) 100 watts is about 1/8 hp. Should drive a small robot. What is the size and weight of your robot. Can you drive the motor directly off a power supply?