中文摘要：

带球铰连接的双刚体航天器系统在无外力矩作用时，其姿态运动可通过连接双刚体航天器的铰关节进行控制，这种由控制输入数目少于系统自由度的系统称为欠驱动系统。利用系统相对于总质心的动量矩守恒这一特性研究了欠驱动双刚体航天器的三维姿态运动控制问题。导出带球铰连接的双刚体航天器系统三维姿态运动控制模型，并将系统的控制问题转化为无漂移系统的运动规划问题，利用最优控制技术和小波分析方法，提出基于小波逼近的遗传算法最优运动规划数值算法。通过数值仿真，表明该方法对带球铰连接的欠驱动双刚体航天器三维姿态运动的运动规划是有效的。

英文摘要：

In the torque-free case, the attitude motion for a spacecraft of coupled rigid bodies is to control by a ballin socket joint. This system is underactuated and characterized by the fact that there are more degrees of freedom than actuators. The optimal motion planning for an underactuated system of coupled rigid bodies is investigated using optimal control technique and wavelet analysis method. The control equations of coupled rigid bodies spacecraft with a ball-in socket joint is obtained by using angular momentum conservation. The control problem of system can be converted to the motion planning problem for a driftless system. In this paper, we make use of genetics algorithm and wavelet analysis method and propose a numerical algorithm for motion planning of an underactuated system. The wavelet approximation is used to optimal control and to generate a feasible trajectory for an underaetuated system. The effectiveness of the numerical algorithm is demonstrated for motion planning of coupled rigid bodies spacecraft by numerical simulation.