Robust H Observer Design for a Class of Nonlinear Uncertain Systems via Convex Optimization

A new approach of robust H
_infin
observer design for a class of Lipschitz nonlinear systems with time-varying uncertainties is proposed in the LMI framework. The admissible Lipschitz constant of the system and the disturbance attenuation level are maximized simultaneously through convex multiobjective optimization. The resulting H
_infin
observer guarantees asymptotic stability of the estimation error dynamics with exponential convergence and is robust against nonlinear additive uncertainty and time-varying parametric uncertainties. Explicit bounds on the nonlinear uncertainty are derived based on norm-wise and element-wise robustness analysis.