40米口径射电望远镜索支撑系统误差分析与补偿

Error analysis and compensation of cable driven parallel manipulators for the forty-meter aperture radio telescope

主要研究了40米口径射电望远镜索支撑系统的误差分析与补偿问题,提出了一种基于索直线模型弹性变形的实时误差补偿方法。在索支撑系统运动学和静力学分析的基础上,建立了兼顾索弹性变形的误差模型,分析了索弹性变形对馈源跟踪精度的影响情况。针对天文规划给定的两条典型路径,根据索弹性变形量和实时控制要求,提出了一种基于索弹性变形的大跨度索支撑系统误差补偿方法,该方法不需要迭代,计算量小。仿真结果表明,该误差补偿方法提高了索支撑系统跟踪精度,同时满足射电望远镜的观测要求。

This paper mainly analyzes the error and its compensation of the cable driven system in a forty-meter aperture radio telescope, and presents a real-time error compensation method based on cable＇s elastic deformation. Kinematics and statics of the cable driven parallel manipulator are analyzed, an error model considering cable＇ s elastic deformation is established and the impact of elastic deformation of cables on the feed precision is indicated. Based on cable＇ s elastic defor- mation and the control of cable driven manipulator, an error compensation method without iteration for big span cable driven parallel manipulators is presented for two typical paths. The simulation results prove that the error compensation method can improve the feed precision and satisfies the design requirement of forty-meter aperture radio telescope.