FAST馈源舱Stewart机构标定

馈源舱系统是FAST工程的核心部件之一。馈源在百米尺度空间内瞬时定位精度要求达到毫米级,因此需要对馈源舱Stewart机构精确标定,以克服加工及装配误差、测量误差、刚度变形以及外界扰动耦合的影响,实现馈源精确定位。本文在分析相关文献对FAST馈源舱研究的基础上,通过对馈源舱Stewart机构标定的实际操作,从测量的角度分析Stewart结构、性能、误差及参数模型等,确定机构标定方案。标定过程包括:规划位姿、用激光跟踪仪实施测量、伺服控制及数据处理等。Stewart机构标定后定位精度显著提高,这对于确保FAST馈源舱空间定位精度有着重要的促进作用。

The Calibration of Stewart Mechanism of FAST's Feed Cabin

The feed cabin system is one of the core components of FAST project,the instantaneous positioning accuracy of the feed is required to reach millimeter level in hundreds of meters.For precise positioning,the Stewart platform on the feed cabin is greatly needed to calibrate accurately to overcome the processing error,assembly error,measurement error,stiffness deformation and external disturbance coupling.In this paper,based on the analysis of relevant literatures on the FAST's cabin,the mechanism calibration scheme is determined by analyzing the structure,performance,error and parameter model of the Stewart platform from the perspective of measurement.The calibration process includes planning pose,measuring with laser tracker,controlling servo,processing data and so on.The positioning accuracy of the Stewart platform is significantly improved after being calibrated,which plays an important role in ensuring the space positioning accuracy of the feed cabin of FAST.