空间绳系机器人姿态容错控制方法研究

Research on Attitude Fault Tolerant Control Method for Space Tethered Robot

在精确姿态控制阶段,由于反作用轮的故障,空间绳系机器人会出现姿态控制失稳的问题,为此,提出了一种空间绳系机器人姿态容错控制的新方法。该容错控制方法利用时间延迟控制算法,将前一个周期的控制量引入到当前控制律中,估计并补偿由于反作用轮故障引起的当前控制量变化。在推导该容错控制方法的基础上证明了它的稳定性,从反作用轮无故障和有故障两个方面,对利用时间延迟控制算法与利用PD控制算法的控制律进行了仿真比较。仿真结果表明,利用时间延迟控制方法跟踪目标姿态精度高、鲁棒性强;将时间延迟控制方法用于调整反作用轮故障状态下空间绳系机器人姿态具有较强的稳定性。

Attitude control iustabihty occurs for reaction wheel failure in the phase of accurate attitude control of a space tethered robot. In order to solve this problem, a new attitude tolerant control method is proposed in the paper. A time-delay control algorithm is utilized to introduced previous one-step control information into the current control law, and the current changed control information is estimated and compensated. The stability of the tolerant control law is proved, and the time-delay control algorithm is compared with conventional proportional-derivative control algorithm from two cases of reaction wheel with failure and without failure. The simulation results show that the time-delay control method have high accuracy and robustness of tracking target attitude, and have high stability for controlling attitude of space tethered robot when a reaction wheel failure occurs.