Balancing an inverted pendulum is a classical benchmark problem for nonlinear control systems, used frequently for validation and evaluation of control algorithms. There are two main types of these: the linear pendulum, which is usually applied to some kind of carriage, and the rotary inverted pendulum, which consists of two parts: a horizontal arm, which can be rotated around its vertical axis by a motor, and a pendulum, which is able to move in a plane perpendicular to the arm and is located at its end. This thesis presents the design and implementation of a controller for a rotary inverted pendulum, realized using industrial motion control devices.
The thesis details the design and verification procedure of the controller for the nonlinear system, including LQ optimal state feedback, reference gains and state observer with load estimator. Interfacing the incremental encoder sensors and the actuator chain made up of a servo amplifier and a DC motor to the controller is also presented. The control system, realized by a PLC, is extended by a graphical human-machine interface. The thesis also presents results of the experiments carried out on the physical system.