I am trying to make a robot arm using VEX 393 motor (with motor controller 29) and Arduino.
I was wondering if I need to use some kind of motor shield between motor controller and Arduino?
I think the motor is pulling too much current and burning the PCB traces.
I wanted to know if I need to use some kind of a shield, which one would work with 393
For the 393 you need to use an H-Bridge to supply it 6 Volts with sufficient current so as not to burn out your Arduino PCB traces. The VEX 3-wire to 2-wire controllers will convert standard 3-wire SERVO outputs to the 2-wire DC motor outputs required by a 393 motor. You can also make them from Allegro H-Bridge ICs. The analog 6-volt power supply for the motor should be separate from the digital 3.3 Volt or 5 Volt supply on your Arduino.