Attack-resilient Estimation of Switched Nonlinear Cyber-Physical Systems

This paper studies attack-resilient estimation of a class of switched nonlinear systems subject to stochastic process and measurement noises. The systems are threatened by both of signal attacks and switching attacks. The problem is formulated as the joint estimation of state, attack vector and mode of hidden-mode switched systems. We propose an estimation algorithm which is composed of a bank of state and attack vector estimators and a mode estimator. The mode estimator selects the most likely mode using the outputs of the state and attack vector estimators. The stability and mean square estimation error bounds for the designed estimator are formally analyzed for the true mode when the hidden mode is time-invariant but remains unknown.