Wang Chenliang, Guo Lei, Wen Changyun, Zhu Yukai, Qiao Jianzhong
IEEE Trans Cybern. 2024 Jul;54(7):4241-4254. doi: 10.1109/TCYB.2023.3295785. Epub 2024 Jul 11.
High-precision and safety control in face of disturbances and uncertainties is a challenging issue of both theoretical and practical importance. In this article, new adaptive anti-disturbance control schemes are proposed for a class of uncertain nonlinear systems with composite disturbances, including additive disturbances, multiplicative actuator faults, and implicit disturbances deeply coupled with system states. Both the cases with known and unknown control/fault directions are investigated. By properly fusing the techniques of disturbance observers and adaptive compensation, it is shown that all closed-loop signals are globally uniformly bounded and the tracking error converges to zero asymptotically, no matter the control/fault directions are known or not. In the case of known directions, the proposed control scheme, for the first time, guarantees asymptotic tracking and L tracking performance simultaneously in face of disturbances and actuator faults. Moreover, novel Nussbaum functions and a contradiction argument are introduced, which allow the system to have multiple unknown nonidentical control directions and unknown time-varying fault direction. Simulation results illustrate the effectiveness of the proposed control schemes.
在面对干扰和不确定性时实现高精度和安全控制是一个具有理论和实际重要性的挑战性问题。本文针对一类具有复合干扰的不确定非线性系统提出了新的自适应抗干扰控制方案，这些复合干扰包括加性干扰、乘性执行器故障以及与系统状态深度耦合的隐式干扰。研究了控制/故障方向已知和未知两种情况。通过适当融合干扰观测器技术和自适应补偿，结果表明，无论控制/故障方向是否已知，所有闭环信号都是全局一致有界的，并且跟踪误差渐近收敛到零。在方向已知的情况下，所提出的控制方案首次在面对干扰和执行器故障时同时保证了渐近跟踪和L跟踪性能。此外，引入了新颖的努斯鲍姆函数和矛盾论证，这使得系统能够具有多个未知的不同控制方向和未知的时变故障方向。仿真结果说明了所提出控制方案的有效性。
