考虑避障的航天器编队轨道容错控制律设计

Fault-tolerant translational control for spacecraft formation flying with collision avoidance requirement

为解决航天器编队飞行过程中的故障容错、障碍规避以及碰撞避免等重要的飞行安全问题,提出了一种新颖的自适应轨道控制方法。该方法将人工势函数制导与滑模控制技术相结合,利用一类特殊的人工势函数来描述障碍规避及碰撞避免等要求,并基于此为航天器编队设计了协同控制器,使得编队在实现目标追踪和构型保持的同时,能够避免相互碰撞并具备规避障碍物的能力。更为重要的是,控制器中自适应律的引入使得闭环系统对执行机构故障、外界干扰及参数不确定性具备良好的容错能力,显著增强了闭环系统的鲁棒性。最后,典型的仿真分析验证了所提控制方法的有效性。

To solve the flying safety issues of spacecraft formation, including fault tolerance and obstacle/collision avoid- ance, a novel adaptive translational control method is proposed. Specifically,the proposed method combines the core ideas of artificial potential function guidance and sliding mode control method. A special artificial potential function is designed to en- code the collision/obstacle avoidance requirement,and then a coordination controller is presented to enable the spacecraft formation to maintain the predetermined configuration while tracking a target,and to be able to avoid all possible collisions between members in formation or with respect to a non-cooperative obstacle. Furthermore,by introducing adaptive laws into the controller,the robustness of the closed-loop system is further improved in respect to external disturbances, parameter un- certainties and even severe actuator faults. Typical simulations are performed to illustrate the effectiveness of the proposed method.