Multisensor fusion fault-tolerant control with diagnosis via a set separation principle

In this paper, a multisensor fusion fault-tolerant control system with fault detection and isolation via set separation is presented. The fault detection and isolation unit verifies that for each sensor-estimator combination, the estimation tracking errors lie inside pre-computed sets and discards faulty sensors when their associated estimation tracking errors leave the sets. An active fault tolerant controller is obtained, where the remaining healthy estimates are combined using a technique based on the optimal fusion criterion in the linear minimum-variance sense, recently proposed in the literature. The fused estimates are then used to implement a state feedback tracking controller. We ensure closed-loop stability and good performance under the occurrence of abrupt sensor faults.