FAST舱-索悬挂系统阻尼识别的原型试验研究  

Prototype Experiment on Damping Identification of the Cabin-cable Suspension System of FAST

作　　者：李辉[1,2] 汤为[1,3] 孙才红[1,2] LI Hui;TANG Wei;SUN Caihong(National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101;Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Beijing 100101;Space Debris Observation and Data Application Center,China National Space Administration,Beijing 100101)

机构地区：[1]中国科学院国家天文台,北京100101 [2]中国科学院射电天文重点实验室,北京100101 [3]国家航天局空间碎片监测预警和应用中心,北京100101

出　　处：《机械工程学报》2023年第13期1-10,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(12273069,11573044)。

摘　　要：FAST望远镜的馈源支撑系统采用六根柔性钢索并联驱动馈源舱的方案,用于实现对目标射电源的初步指向和跟踪功能。馈源舱和六索构成度达600 m的巨型柔性舱-索悬挂动力学系统,其系统阻尼是影响FAST指向和跟踪精度的重要因素。对刚刚建成的舱-索悬挂系统原型的阻尼比进行大量的测试分析,根据馈源舱的运动范围分别选取4个不同的馈源舱位置进行舱-索系统振动测试,试验过程中主要采集馈源舱上不同位置点的振动加速度时程曲线作为主要测试数据,并对数据采用ITD法识别其模态频率和阻尼比。测试结果表明,FAST舱-索悬挂系统的阻尼比不低于0.003 5,相比以往的缩尺模型具有更高的能量耗散和动力学控制稳定性,为FAST的控制算法和调试提供重要参考依据。In the conceptual design of the feed support system of Five-hundred-meter Aperture Spherical radio Telescope(FAST),the feed cabin is driven by 6 parallel flexible steel cables so that the telescope can be roughly aligned to object radio source and follows its track.The cabin and the 6 cables then comprise in dynamics of a huge flexible cabin-cable suspension system with a span of 600 m.Its damping performance is a very important influence factor on the final pointing and tracking accuracy of FAST.A set of prototype tests to identify its damping ratios just after the cabin-cable suspension system is built.First,4 typical cabin positions are selected respectively for vibration tests according to the movement range of the cabin.Then several acceleration-time curves relating to different points on the cabin are measured as the main test data.Finally Ibrahim time domain(ITD) method is used to identify natural frequency and damping ratio from the data.The test results prove that damping ratio of the prototype is not lower than 0.003 5,with higher potential energy dissipation and control stability than the previous scaled models,which provides important reference for the control algorithm and commissioning of FAST.

关 键 词：FAST 舱-索悬挂系统 动力学 原型测试 阻尼识别 

分 类 号：TG156[金属学及工艺—热处理]