# Handling stiction with variable structure control

## Abstract

When the control system falls in a class obeying non-Lipschitzian (or “non-smooth”) dynamics, the conventional nonlinear theory can not be readily applied. Among the common non-smooth nonlinearities are those which are discontinuous in the state variables. Existence of such inherent right hand side discontinuities may induce undesirable stiction while hardening the control task during reference tracking. In this work, we analyze the “stiction” phenomenon in depth using analogies from the sliding mode control theory and propose a multi layer variable structure reference tracking controller for a class of systems in their companion forms. Results for an interesting physical example is provided to clarify the concepts.

## Keywords

Control Input Reference Signal Slide Mode Control State Space Representation Variable Structure Control## Preview

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