Robust fault detection filter design for multiple model systems via nonsmooth optimization approach

This paper considers a robust fault detection filter (RFDF) problem for multiple models subject to faults and disturbances. The worst-case disturbance robustness measure, the H_∞ norm, and the worst-case fault sensitivity measure, the H_- index, are considered. The designed robust fault detection filter and threshold are independent of the operational mode of the system, which could be formulated as a constrained optimization problem to solve using nonsmooth optimization method. Considering the faster processing, the reduced order RFDF is designed by the proposed nonsmooth optimization method. The effectiveness of the proposed method is illustrated on an application: a robust fault detection filter for a vehicle lateral dynamics switched system with 3 subsystems.