空间交会对接航天器的对接端口一般位于航天器表面,并非位于质心,但传统的相对运动建模往往采用航天器质心作为参考点,致使在实际操作中需要额外的针对对接端口相对位姿进行规划,无疑会降低操作任务完成效率.为此,基于旋量描述,研究了航天器非质心点间的相对运动建模方法,首先通过引入恰当的转换算子,建立了非质心对接点之间的相对速度旋量,然后利用基本力学原理和旋量理论,详细推导并得到了非质心点相栐运动姿轨耦合模型,该模型不仅避免了姿态解算的奇异,而且姿轨描述形式统一,对航天器控制系统并无额外要求,有利于协同控制器设计.利用此模型,考虑空间摄动及未知干扰影响,文中设计了一种将非线性反馈控制和基于状态偏差对数的PD控制相结合的控制律,并证明了稳定性,完成了仿真验证.结果表明该方法可行、姿轨协调控制效果良好、可精确实现对接端口的对接状态,为空间相对运动姿轨耦合建模与协同控制系统设计提供了理论参考.%The docking port of the spacecraft in rendezvous and docking is usually located on the surface of the spacecraft .It is not located in the center of mass .However , the traditional relative motion modeling often uses the spacecraft centroid as the reference point , so that the actual operation requires additional planning for the docking port, will undoubtedly reduce the efficiency of operational tasks .In this paper, based on the spin description , the relative motion modeling method between the non-centroid of spacecraft is studied .Firstly, by introducing the ap-propriate conversion operator , the relative velocity rotation between non-centroid pairs is established , and then the coupled model of non-centroid relative motion and attitude is deduced by using the mechanics principle and spin theory .The model not only avoids the singularity of attitude calculation , but also has the unified form of description and there is no requirement for the spacecraft control system , which is conducive to collaborative controllers design . Based on this model , considering the influence of spatial perturbation and unknown disturbance , this paper designs a control law combining nonlinear feedback control and PD control based on logarithm of state deviation logarithm , and proves the stability and completes the simulation .The results show that the proposed method is feasible and has good control effect , and the docking state of the docking port can be realized accurately , which provides a theoreti-cal reference for coupling modelling of space relative motion and the design of the coordinated control system .
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