The first step in controlling your air hockey playing robot is to control the position of the three stepper motors in your paddle system. To understand how to do this, let's start by exploring how stepper motors work. The following is an image of a stepper motor:
Stepper motors are a bit different from the servos that you used in Chapter 5, A Robot That Can Draw. Stepper motors operate in a similar way to DC motors as even they can rotate continuously. However, the stepper motor has the ability to drive the motor in small steps. For a tutorial on the specifics on stepper motors, refer to https://en.wikipedia.org/wiki/Stepper_motor.
Stepper motors can be a bit difficult to work with as the control is more complex than DC or servo motors. Fortunately, the three-dimensional printer movement has created an entire community around designing the hardware and software to make this process easier. One important factor to be considered for the project is...