针对卫星交会对接中相对姿态和位置的控制问题,设计一种6自由度(DOF)气浮台,并推导出描述两个气浮台模拟卫星交会对接运动的耦合6自由度(DOF)动力学模型。为解决气浮台模拟空间失重环境中的重力力矩干扰问题,设计一种基于应用新颖的快速非奇异终端滑模面的自适应有限时间控制器的自动平衡系统,估计出质心位置,通过控制三个平衡质量块补偿姿态平台质心与旋转中心之间的位置偏差。李雅普诺夫理论推导和仿真结果表明,该方法可以快速完成对姿态平台质心位置的准确估计,实现质心与旋转中心的高度重合。
For the problem of relative attitude and position control involved in satellite rendezvous and docking, a 6 degree-of-freedom (DOF) air bearing table is designed, and a coupled 6-DOF dynamics model is developed to describe that two air beating tables simulate the motion of rendezvous and docking. To reduce the gravitational torque involved in creating a space-like environment with the air bearing table, an automatic mass balancing system based on an adaptive finite-time control scheme which uses a novel fast nonsingular terminal sliding mode surface is designed, then the center of mass is estimated out, and based on this, three proof masses are actuated to compensate for the center of mass offset from the center of rotation. The Lyapunov theory and the simulation results show that the method proposed can accurately estimate the center of mass of the attitude platform rapidly, and realize the center of mass being exactly aligned with the center of rotation.