Robust output feedback using sliding mode control

A general sliding mode output feedback algorithm is developed that takes into account parametric uncertainty and external disturbances provided certain bounds are known. It has been assumed that the number of states is greater than the number of sensors and that there can be a mismatched disturbance. The details of an eigenvalue perturbation analysis for an uncertain matrix are presented. A boundary layer has been introduced around each sliding surface to eliminate the chattering phenomenon. The results from numerical simulations are presented to corroborate the validity of the proposed controller.