This paper is concerned with the consensus tracking problem in nonlinear multi-agent systems against external disturbances and multiple actuator faults. The nonlinear dynamics are unknown and the leader’s input is unavailable to any follower. By using finite-time Lyapunov stability theory, a distributed discontinuous protocol is developed. On this basis, a fixed-time control protocol is further designed to obtain a settling time regardless of initial conditions. In addition, the practical finite-time consensus and practical fixed-time consensus are investigated by the adaptive technique, under which the bounds of the faults can be estimated online adaptively. The innovation of this work lies in the fact that the finite/fixed-time consensus problem is solved when multiple faults and mismatched nonlinearity are simultaneously considered. The relationship between the settling time and design parameters is well established. Finally, some numerical simulations are given to verify the effectiveness of the theoretical results.

中文翻译：

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非线性多智能体系统对执行器故障和干扰的有限/固定时间一致性

本文关注的是非线性多智能体系统中针对外部干扰和多执行器故障的一致性跟踪问题。非线性动力学未知，任何跟随者都无法获得领导者的输入。利用有限时间Lyapunov稳定性理论，开发了一种分布式不连续协议。在此基础上，进一步设计了固定时间控制协议，以获得不受初始条件影响的稳定时间。此外，通过自适应技术研究了实用的有限时间共识和实用的固定时间共识，在此基础上可以自适应地在线估计故障范围。这项工作的创新之处在于，当同时考虑多个故障和失配非线性时，解决了有限/固定时间一致性问题。稳定时间和设计参数之间的关系已经很好地建立起来。最后通过数值模拟验证了理论结果的有效性。