Evaluation of a Sliding Mode Fault Tolerant Controller on the MuPAL-Alpha Research Aircraft

Abstract

This paper presents the piloted flight test results of a sliding mode fault tolerant control scheme implemented on the Japan Aerospace Exploration Agency's MuPAL-alpha research aircraft. These results represent unique piloted validation tests of a sliding mode fault tolerant control allocation scheme on a full-scale aircraft operating in the presence of actuator faults. The control law used here does not require the presence of a fault detection and isolation unit and therefore in the event of faults/failures, the actuator effectiveness levels are unknown. In the absence of this information, a fixed control allocation mechanism has been used in order to retain nominal fault-free performance. The control scheme has been implemented on the lateral-directional motions and incorporated within the experimental fly-by-wire system. Piloted flight test results show that close to nominal tracking performance can be maintained despite the presence of unknown actuator faults as well as actuator uncertainties.