基于快速终端滑模的航天器自适应容错控制

Adaptive Fault Tolerant Control for Spacecraft Based on Fast Terminal Sliding Mode

针对存在不确定的执行机构部分失效故障和未知外界扰动的航天器姿态跟踪控制问题,提出了一种基于自适应快速终端滑模控制的容错控制方法。在没有故障检测与诊断信息的情况下,采用快速终端滑模控制原理,利用自适应算法在线估计得到的故障信息,设计具有鲁棒性的容错控制器,使系统在执行机构故障发生时,能在有限时间内以指数收敛,实现系统有限时间渐近稳定,以及对航天器的容错控制和干扰的抑制。仿真结果表明,与基于普通滑模控制器的容错控制相比,该方法在保证系统鲁棒性和可靠性的同时,具有更快的收敛速率,实现执行机构故障时有效的航天器姿态跟踪控制。

A novel method for designing fault-tolerant controller is proposed based on adaptive fast terminal sliding mode control for tracking control problem of spacecraft with unknown external disturbances and an uncertain actuator fault.In this approach,a robust controller based on fast terminal sliding mode control scheme is designed by using an adaptive approach to estimate fault information of actuation failure in the absence of fault detection and diagnosis value of actuator fault.By using this approach,globally asymptotically stability and fault tolerant control the closed-loop system are achieved in a finite time while the disturbance is suppressed when actuaor failures occurr.Numerical simulations have demonstrated that the proposed approach should force the system to the equilibrium points at a fast convergence rate while improve the robustness and reliability compared with common sliding mode method.