Actuator fault accommodation strategy for a team of LTI multi-agent systems

Abstract

A cooperative actuator fault accommodation strategy for a team of linear time-invariant (LTI) multi-agent systems with a switching topology and directed communication network graph is studied in this paper. The faults could occur in more than one agent simultaneously and the fault severity is not needed to be precisely estimated. The proposed fault accommodation strategy is performed in two levels: the agent level fault recovery (ALFR) and the team level fault recovery (TLFR). Whenever a fault is detected, the recovery strategy is to locally recover faulty agents based on inaccurate estimates of the faults in the first step and to reconfigure the weights of the information flow graph in the second step. The proposed strategy is based on the sub-optimal solution of a bi-linear matrix inequality (BMI) and guarantees the consensus achievement of the team. The stability properties of the proposed controller and the recovery strategy are investigated based on Lyapunov analysis. The effectiveness of our proposed consensus algorithm is illustrated by performing numerical simulations for a team of ten agents and the performance of our strategy is compared with the centralized and decentralized fault recovery approaches in the literature.