A Robust State Estimation Method for Unknown, Time-Varying and Featureless Aircraft Sensor Failures

Fault-tolerant state estimation is necessary for analytical redundancy in aviation safety, but complicated fault conditions pose a major challenge to reliable estimations. In this paper, we propose a new state-estimation method based on an intermittent-measurement Kalman filter, a maximum-likelihood estimation rule, and the Gaussian mixture reduction. This method is robust to time-varying and featureless faults, and requires no past history of innovation errors to perform fault detection and isolation, leading to the easy implementation and improved accuracy under severe sensor-failure conditions. With an example application of monitoring the rotation speeds of a two-spool jet engine in simulations, the effectiveness of the proposed method is verified.