Driving Stepper and Servo Motors
Jeremy Blum · 2019
DC motors serve as excellent drive motors, but they are not recommended for precision work because they have no built-in feedback mechanism and they are velocity-controlled rather than being position-controlled. Servo motors enable precise positioning and can be controlled using the Arduino servo library. Stepper motors are another kind of motor that “step” in precise increments; they are perfect for building things like 3D printer gantries and precision gauges and instruments. This chapter discusses both servo motors and stepper motors and explains how to control both from the Arduino. Infrared (IR) distance sensors return analog values representing distances detected by bouncing infrared light off objects. The Arduino has internal pull-up resistors than can be enabled on input pins. Programmers can use the millis() function to track elapsed time in their Arduino sketches.