Output Feedback Sliding Mode Control of Uncertain Systems in the Presence of State Delay with Applications

This chapter considers the development of sliding mode control strategies for linear, time delay systems with bounded disturbances that are not necessarily matched. The emphasis is on the development of frameworks that are constructive and applicable to real problems. For many systems it may not be practical to measure all the system states and therefore a static output feedback sliding mode control design paradigm is considered. The novel feature of the method is that Linear Matrix Inequalities (LMIs) are derived to compute solutions to both the existence problem and the finite time reachability problem that minimize the ultimate bound of the reduced-order sliding mode dynamics in the presence of time varying delay and unmatched disturbances. The methodology is therefore constructive and provides guarantees on the level of closed-loop performance that will be achieved by uncertain systems which experience delay. An uncertain model with both matched and unmatched disturbances from the literature provides a tutorial example of the proposed method. A case study involving the practical application of the design methodology in the area of liquid monopropellant rocket motor control is also presented.