A UNIFYING DESIGN OF SLIDING MODE AND CLASSICAL CONTROLLERS

A theory is given to unify output sliding mode control and classical c ontrol. The idea is based on defining the sliding variable in such a w ay that once the system gets into sliding, the classical controller tr ansfer function is realized. This idea leads to the development of a h ybrid sliding-and-classical controller which retains the merits of bot h types of controllers on one hand and eliminates their respective lim itations on the other. The proposed method is robust and applies to no nminimum phase SISO systems. No state measurement is required.