Nonlinear control of a single-link flexible joint manipulator using differential flatness

In this paper, a nonlinear feedback controller is proposed for a single link flexible joint manipulator based on the concept of differential flatness. The control design is approached from the perspective of using input state feedback linearization via the flatness property of the robot. It is shown that the nonlinear dynamics of the manipulator satisfies the controllability and involutivity conditions required for the selection of a flat output. With the flat output, trajectories of motion are generated. A feedback controller is then designed to track the trajectories. Tracking results show the effectiveness of the proposed flatness based control scheme.