Reaching Conditions in Variable Structure Systems for Output Feedback Control

This paper investigates the issues surrounding the reaching conditions in variable structure systems with output feedback control. The control law is formulated so that static output feedback can be applied to variable structure systems as opposed to state feedback or estimated state feedback. The control law is chosen to ensure that the reaching conditions are satisfied. The control structure is such that certain parameters directly affect the time to reach the sliding surface. Several procedures are devised to select these parameters so that not only the reaching conditions can be satisfied with flexibility but also the time to reach the sliding surface can be adjusted. Numerical examples are given that demonstrate the techniques developed in this paper.