Robust feedback linearization through sliding mode control

The author presents a robust technique for designing compensators for a certain class of nonlinear systems following the philosophy behind input-output linearization and sliding mode control. The technique takes advantage of a robust equivalent feedback linearization using sliding mode theory and then superimposes linear design algorithms in order to shape the loop operator (loop transfer function) of the feedback linearized system. Robustness issues are addressed; when the external disturbances to the system and modeling parameter uncertainties are bounded and satisfy the matching conditions, the nonlinear system can be robustly linearized. The proposed scheme has enough parameters to give flexibility in the choice of the desired closed-loop characteristics. At the same time, it leaves the designer with the responsibility of selecting the following parameters: boundary layer, strength of attraction to the sliding surface, and bandwidth.<>