Hi, I am planning to make a small robot that just moves around. In order to control the motors I bought a Motor Shield from LadyAda. All seems fine and the motor spins when required (it does it really fast aswell) however once I put the robot on the ground the motor stops. I can hear buzzing but it does not move. When I lift the body it resumes spinning as normal. I am using two general motors (they didn't have any specifications) that I bought from Kitronik.
Why can't the motor manage to push the robot forward? Is there any other type of motor I should use that you recommend? (from eBay please).
Note: the robot consists of two motors, Arduino Uno, Motor Shield, 4xAA batteries and a Acrylic base that everything is mounted on.