Simultaneous Fault Estimation and Fault-Tolerant Consensus Control for Multi-Agent Systems Against Multiple Time Delays

This article addresses the problems of robust fault estimation (FE) and fault-tolerant control (FTC) for nonlinear multi-agent systems (MASs) subject to faults, multiple time-varying delays, and exogenous disturbances. First, by utilizing the output estimation error and relative output estimation error, an FE observer is constructed to estimate the states and faults of a single agent simultaneously. Second, an observer-based state feedback control protocol is proposed to eliminate the influences of faults and guarantee the consensus. Third, an $ H_{\infty }$ existent condition of control for the closed-loop system is translated into a convex linear matrix inequality (LMI) optimization problem by constructing special matrices and matrix inequalities. Finally, the effectiveness of the proposed methods is demonstrated via two illustrative simulation examples.