Hybrid controller for rotational inverted pendulum systems

In this paper, a controller designed by energy control technique and servo state feedback with minimum-order observer control algorithm to swing up the pendulum of the rotational inverted pendulum system from the natural pendent position to around the upright position and to stabilize the pendulum in upright position is proposed. The proposed control scheme composes of two parts. The first part is the swing-lip control using the energy-based controller and the second part is the stabilizing control using the servo state feedback with minimum-order observer controller. From the implementation of the controller to the rotational inverted pendulum system in laboratory, the pendulum can be swung up within a short period of time with small oscillation of the base angle. Furthermore, without changing the parameters of the proposed controller, the responses of the system when changing the length of the pendulum is also shown to demonstrate the robustness of the proposed control system.