基于预定性能滑模的四旋翼无人机容错控制

Fault-Tolerant Control of Quadrotor UAV Based on Prescribed Performance Sliding Mode

针对气动阻尼系数和外部干扰未知、执行器故障和暂稳态性能约束的四旋翼无人机系统,提出一种自适应预定性能滑模容错控制策略。先将无人机动力学模型转换为位置子系统和姿态子系统,位置子系统采用自适应控制方法对执行器故障和阻尼系数进行估计,并在暂稳态性能约束情况下提出新的预定性能滑模容错控制器;对于姿态子系统的执行器故障和未知外部干扰问题,基于扰动观测器和自适应控制方法,提出了预定性能滑模控制器。克服了已有的预定性能控制研究中阻尼系数和外界干扰的界已知以及未考虑故障发生的限制,提高了控制系统容错能力和抗干扰能力。利用Lyapunov稳定性理论证明了控制系统是一致最终有界稳定的,且跟踪误差满足预定的暂稳态性能约束。最后利用Matlab仿真验证了所提出控制方法的优越性和可行性。

An adaptive prescribed performance sliding mode fault-tolerant control strategy is proposed for a quadrotor UAV system with unknown aerodynamic damping coefficients,unknown external disturbances,actuator fault and transient steady-state performance constraints.Firstly,the dynamics model of UAV was converted into posi⁃tion subsystem and attitude subsystem.Then,an adaptive control method was used to estimate actuator faults and damping coefficients in the position subsystem,and a new prescribed performance sliding mode fault-tolerant control⁃ler was proposed under transient steady-state performance constraints.For the problems of actuator faults and un⁃known external disturbances in attitude subsystem,a prescribed performance sliding mode controller was proposed based on disturbance observer and adaptive control method,which overcomes the limitations of knowing boundary of damping coefficients and external disturbance,and not considering fault in the existing research on prescribed per⁃formance control,and the fault-tolerant ability and anti-interference ability of the control system are improved.Fur⁃thermore,the control system is uniformly ultimately bounded stable which is proved by using Lyapunov stability theo⁃ry,and the tracking errors can satisfy the prescribed transient and steady-state performance constraints.Finally,Matlab simulation shows the superiority and effectiveness of the proposed method.