Continuous Fixed-Time Fault-Tolerant Formation Control for Heterogeneous Multiagent Systems Under Fixed and Switching Topologies

This article proposes a novel continuous fixed-time fault-tolerant formation control framework for heterogeneous multiagent systems (HMASs) involving unmanned aerial vehicles (UAVs) and unmanned ground vehicles (UGVs) with actuator faults and model uncertainties under fixed and switching topologies. Firstly, to estimate the information of actuator faults and uncertainties for each follower, a fixed-time observer is constructed. Then, an integral fixed-time sliding mode surface is designed such that the merits of high robustness, exact transient response and fixed-time convergence can be achieved. Subsequently, based on the integration of disturbance observer, high-order sliding mode and backstepping technologies, distributed and decentralized continuous fixed-time formation tracking control schemes under actuator faults are developed of the HMASs in the X-Y axis and Z axis, respectively. The proposed algorithm can not only handle time-varying formation in a timely manner, but also provide continuous control action under fixed and switching topologies. It is theoretically proved that the designed protocol can realize the expected fixed-time formation missions by employing the Lyapunov stability theorem. Finally, simulation results verify the effectiveness of the designed fixed-time control algorithm.