A LMI approach to fault detection filter design for networked control systems

Problems related to fault detection filter design for networked control systems with uncertain network-induced delay and L_2 norm bounded unknown input are studied. By introducing a new optimization performance index, the design of observer-based robust fault detection filter for networked control systems can be formulated as a H_∞-filtering problem, and further be solved by suitably selecting weighting matrix and observer gain matrix, which could maximize the sensitivity of residual to fault and simultaneously guarantee the robustness to network-induced delay as well unknown input. The solvable condition of this optimization problem and further the solutions are derived by employing linear matrix inequality techniques. A numerical example illustrates the effectiveness of the proposed approach.