Synchronous interval observer design for switched LPV systems using multiple quadratic ISS-Lyapunov functions

This paper deals with the problem of robust state estimation for switched LPV continuous-time systems with measurable and unmeasurable scheduling parameters. The switching law is assumed to be uncontrollable but online available, while the unmeasurable varying parameters are assumed to be bounded with a priori known bounds. The proposed approach is based on switched interval observers which provide guaranteed lower and upper bounds allowing to evaluate the set of admissible values of the real state vector. The stability and positivity conditions of the switched interval error are expressed in terms of linear matrix inequalities (LMIs), which have been established using multiple quadratic ISS-Lyapunov functions (MQLF) and average dwell-time concept. In order to enhance estimation accuracy and robustness an explicit bound of the interval error is guaranteed. The proposed approach is applied to robust estimation of vehicle lateral dynamics. Tests are conducted on experimental data in order to prove the effectiveness of the proposed switched interval observer.