Combining sliding-mode and optimal methods for experiments on controlling a single-link flexible arm

This paper presents a combined control scheme for flexible link robotic manipulators, which is based on considering the flexible mechanical structure as a system with slow (rigid) and fast (flexible) modes that can be controlled separately. The rigid dynamics is controlled by means of a robust sliding-mode approach with well-established stability properties while an LQR optimal design is adopted for the flexible dynamics. Experimental results on a laboratory single flexible arm show that this composite approach achieves good closed loop tracking properties both for the rigid and the flexible dynamics