三维充液航天器的位置和姿态联合控制

考虑充液月球着陆器悬停避障阶段的控制问题，采用三维球摆作为液体晃动部分的等效模型.针对球摆与刚体耦合的三维动力学模型，给出动力学模型的矢量方程及各矢量在本体系的投影坐标，设计位置和姿态联合控制器.所设计的控制器可以稳定航天器刚体的位置和姿态，且只依赖刚体的位置和姿态，不依赖晃动角或者动力学方程，利于工程应用.利用LaSalle不变原理分析闭环系统的稳定性，给出期望姿态为竖直时系统渐近稳定的控制器参数选择依据.最后数值仿真验证控制方法的有效性.

Passive Control for a Three Dimensional Liquid Filled Spacecraft

The hazard avoidance control for a liquid filled lunar lander is considered in this paper. A three dimensional spherical pendulum is used for the mechanical equivalent model of the liquid sloshing. Considering the three dimensional dynamics combined of spherical pendulum and rigid body of spacecraft, the vector dynamics equations are given as well as the projected coordinates of each vector variables. With these equations, a combined position and attitude controller is designed, which can stabilize the position and attitude of the rigid body. Moreover, this controller only depends on the position and attitude of rigid body, and independent of liquid sloshing angle or sloshing dynamics. It thus leads to the convenience for the practical applications. The stability of closed loop system is given via LaSalle invariance principle, and the control parameters are suggested for the asymptotical stability of the system when the reference vertical attitude is chosen. Finally the effectiveness of the proposed control is validated via numerical simulations.