An actuator is an electro-mechanical device that translates electrical energy into motion. A DC motor is a perfect example of a basic actuator. Similarly, servo motors, stepper motors, and hydraulic arm levers are all examples of actuators that are used heavily in the world of hardware automation and robotics.

DC motors are of two main types: brushed and brushless. There are fundamental differences in the way brushed and brushless motors are designed. To think of it in a very simple manner, brushed DC motors make use of physical contact points, known as brushes, between their current supply and the Commutator (the motor part responsible for causing the rotor to move). Whereas, brushless DC motors do not use physical brushes; instead they usually use multiple permanent magnets around the rotor, but not in direct contact. Brushed motors are the commonly found low cost, noisy motors that we are used to seeing in toy cars. Whereas, the brushless motors are more sophisticated, almost noiseless and higher priced components; usually found inside expensive electronic gadgets such as camcorder shutters. In this chapter, we will take a look at the basic aspects of interfacing and controlling easily available brushed DC motors.