Adaptive variable structure control of nonlinear systems

Variable Structure Control(VSC) with sliding mode is a special type of control technique that is capable of making a control system very robust with respect to system parameter variations and external disturbances. The chattering of the VSC signal can be reduced by several methods. One way is to augment the system with an integrator to isolate the system from the VSC control signal which causes the chatter. In addition, the magnitude of the switching function can be reduced by the estimation of the uncertainty. In this work, we designed a Variable Structure Controller for linearizable systems. The concept of augmented plant together with the identification of the uncertainty through an observer has been used to reduce the chattering. A simulation study is reported in illustration.