24: Motors

The stepper motors are required to lift the elevator cab to the correct floor. The stepper motor's precision makes it an ideal device for achieving accurate precision. A few trial and error tests were required to determine the number of "steps" between floors. A stepper motor does not spin freely on it’s own when connected to a
current. It is a motor controlled by a series of electromagnetic coils. The
center shaft has a series of magnets mounted on it, and the coils surrounding
the shaft are alternately given current or not, creating magnetic fields which
repulse or attract the magnets on the shaft, causing the motor to rotate. The current is regulated by the Arduino micro controller which is programmed in Arduino programming language (based on Wiring). Like other motors, stepper motors require more power than a microcontroller can give them, so a separate DC power supply is required. Typical voltages for a stepper might be 5V, 9V, 12V, 24V.