Control of an Inverted Pendulum (Pendubot)

Abstract: The aim of this project is to control a double linked inverted pendulum called the "Pendubot". A cascade control scheme has been developed at Laboratoire d'Automatique (EPFL) for this purpose. The structure of the cascade scheme is: Input-output feedback linearization and a linear controller in the inner-loop to assure the control of the fi-angle, the outer loop is responsible for stabilizing the psi-angle. The whole idea is to make the inner loop much faster than the outer so to separate the system and to allow to control the fi and the psi angle separately, This so called timescale separation is necessary for the cascade schemes efficiency. This speed difference between the loops is accomplished by the linear controller. In the outer-loop three different types of controllers will be implemented: a PD-structured controller, a non-linear controller and a Model Predictive controller (MPC).