Trajectory Tracking Control of a Very Flexible Robot Using a Feedback Linearization Controller and a Nonlinear Observer

Flexible robots can be modeled as underactuated multibody systems since they generally have less control inputs than degrees of freedom for rigid body motion and deformation. The flexibilities must be taken into account in the control design. In order to obtain high performance in the end-effector trajectory tracking, an accurate and efficient nonlinear controller is required. In this paper, a nonlinear feedback controller based on the feedback linearization approach using all the states of the system is designed and carefully tested on a very flexible parallel lambda robot. The simulation and experimental results show that the end-effector tracks a trajectory with higher accuracy compared to previous works.