Observer based tip tracking control of two-link flexible manipulator

In this paper, a non-linear observer is designed to estimate the time derivatives of the flexural degrees of freedom that are not conveniently or economically accessible. A non-linear control strategy is developed based on input-output linearization. This is achieved by defining new outputs near the end point of the arm that results in stable zero dynamics. The control objective is considered tip position tracking of a desired trajectory. Stability of the observer error dynamics is proved by Lyapunov theorem. The controller performance is demonstrated by numerical simulation on a two-link flexible manipulator with a tip load in vertical plane.