I would like to purchase a motor controller. However I am not sure as to the difference between a pololu motor controller and a motor driver. All I want this device to do is to controll (vary) the speed of my motors whether going forward or in reverse. I am not too interested in feedback or turning left/right.
The difference between a ‘controller’ and a ‘driver’ is what kind of signal each takes.
A motor driver is basically just a breakout board for a motor driving chip. To use a motor driver for speed and direction control, you would need to use another device (such as a microcontroller) to generate a pulse width modulated square wave signal to control the speed of the motor, and a few high/low logic lines to control the direction.
A motor controller is essentially a motor driver paired with a microcontroller on the same board. This on-board microcontroller takes care of generating the PWM and logic signals, and provides you with other interfaces to specify the motor speed and direction (for example, serial, USB, RC, analog voltage).
So the first question is how do you want to specify the speed of the motor (turning a dial, from a computer with a USB port, etc…)? Then you need to match the controller to your motor and power requirements.
A controller is used to just control the rotation of the motor whereas driver controls the electrical energy sent to the motor and sent the electrical energy in varying form.