Optimal Robustification of Linear Quadratic Regulator

This paper presents a robust control design for linear systems with matched external disturbances based on linear-quadratic regulator (LQR) and sliding mode control (SMC). The design includes a quadratic integral sliding manifold for which LQR is equivalent control, so it does not force the system to change its optimal dynamics during the transient response like in other commonly used state-of-the-art SMC design procedures. The simulation study suggests that the proposed control design robustifies optimal LQR with minimal deterioration of optimality.