The linear inverted pendulum (or linear pendulum, lin. pen for short) is a classical physics experiment used to explain the control theory and system dynamics. Therefore, it has been used as one of the primary systems used to test and compare control strategies. In an inverted pendulum system, which is an open-loop unstable system, it is desired to stabilize the system by reciprocating motion to stabilize it. It is also used as a common method for testing control algorithms.