带刚性臂的空间绳系机构偏置控制
陈辉，文浩，金栋平，胡海岩
摘要:通过系绳与机构间串联的可控刚性臂作为偏置控制器，对由轨道偏心率弓』起的系统面内运动发散动力学问题进行分析，研究了空间绳系机构系统的位置-9姿态最优控制问题．利用Gauss伪谱法，将绳系机构位置与姿态最优控制离散为大规模动态规划问题，借助非线性规划方法求解，并引入状态反馈补偿来抑制系统的初始扰动．数值结果表明，偏置机构的引入提高了系统面内运动发散的轨道偏心率，机构的位置与姿态控制可相互解耦，以系绳张力、刚性臂转动加速度和绳系机构上的动量轮作为控制输入，降低了动量轮的控制力矩，状态反馈跟踪补偿控制器有效消除了系统的扰动影响．
关键词：可控刚性臂；空间绳系机构；偏置控制；Gauss伪谱；状态反馈
Offset control of a space tethered mechanism using a controllable rigid arm
Hui Chen, Hao Wen, Dongping Jin, Haiyan Hu
Abstract：The paper presents the offset control and its optimal control problem of the in-plane motion of space tethered mechanism with a controllable rigid arm attached. The Poincar6 map of the in-plane motion shows that the orbit eccentricity corresponding to the in-plane motion for which the divergence occurs would have an increase when the controllable arm is introduced. By using the Gauss pseudospectral method, the nonlinear optimal control problem under consideration is discretized to a large-scale optimization problem first, and then the method of nonlinear programming is used to obtain numerical solutions. The numerical results show that the position and attitude dynamics of the tethered mechanism can be decoupled and the proposed control scheme is able to bring the states of the tether mechanism to the desired values by adequately adjusting the tether tension, the angular acceleration of the arm and the moment of momentum wheel. In addition, the proposed scheme with a state feedback can effectively suppress the effect of the disturbance.
Keyword：controllable rigid arm; tethered mechanism; offset control; Gauss pseudospectrum; state feedback
原文链接：http://phys.scichina.com:8083/sciG/CN/Y2013/V43/I4/363
