Sliding mode observer for systems with mismatched parametric uncertainties

A sliding mode observer (SMO) analysis and synthesis framework for systems with mismatched parametric uncertainties is proposed. Stability of the uncertain state estimation error system is addressed using the concept of uniform ultimate bounded stability, also known as practical stability. The design methodology involves linear matrix inequality methods and employs a polytopic description for designing the gain matrices of the SMO. A numerical example illustrates the design methodology and its effectiveness.