Fault Estimation and Fault‐Tolerant Consensus Tracking Control for Nonlinear Multi‐Agent Systems With Exogenous Disturbances

ABSTRACT This article addresses the fault estimation (FE) and fault‐tolerant consensus tracking (FTCT) problem for nonlinear multi‐agent systems (MASs) subject to unmeasurable leader states, actuator/sensor faults, and exogenous disturbances. The centralized‐distributed hybrid observers are constructed for each agent by integrating relative output information from neighbors and available leader signals. This observer enables simultaneous estimation of agent states, unmeasurable leader states, actuator/sensor faults, and exogenous disturbances. Based on the estimation information, the FTCT protocol is developed. The observer and consensus protocol are constructed separately to avoid parameter coupling. Utilizing the Schur decomposition, the LMI approach is proposed to solve the observer parameters. Finally, the effectiveness of the proposed method is verified via two simulation examples.