Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and c...Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.展开更多
提出采用LDRA(Liverpool Data Research Associates Ltd.)TESTBED测试工具辅助完成高可靠性的军用软件测试工作,并通过测试实例阐述了该工具在航天软件测试中的应用方案。结果证明,合理使用该工具,能够有效避免人为失误,提高软件测试的...提出采用LDRA(Liverpool Data Research Associates Ltd.)TESTBED测试工具辅助完成高可靠性的军用软件测试工作,并通过测试实例阐述了该工具在航天软件测试中的应用方案。结果证明,合理使用该工具,能够有效避免人为失误,提高软件测试的效率和信息采集的准确度。展开更多
基于数控系统绕刀具中心旋转(Rotation tool center point,RTCP)功能,R-test装置被用于多轴联动数控机床的联动精度检测与标定。该仪器通过三个直线位移传感器测量安装于主轴的球头球心空间位置,从而可测量机床多轴联动时的刀具中心点...基于数控系统绕刀具中心旋转(Rotation tool center point,RTCP)功能,R-test装置被用于多轴联动数控机床的联动精度检测与标定。该仪器通过三个直线位移传感器测量安装于主轴的球头球心空间位置,从而可测量机床多轴联动时的刀具中心点位置误差。在分析测量原理的基础上,提出最大测量空间和测量敏感度的两个用于评价测量性能的指标及相应的数值算法,得到一种R-test装置结构优化设计方法。在选择通用球头芯棒与长度计的情况下,通过约束分析得到测量杆安装圆直径、测量杆与基准面夹角两个关键尺寸的设计区间,利用蒙特卡罗法搜索得到这两个关键尺寸的最优解,完成结构优化设计。仿真表明,优化设计得到的R-test测量装置具有最佳的测量敏感度,可测区域大于半径为4 mm的球体,能满足实际测量精度和测量空间需要。展开更多
基金Supported by National Nature Science Foundation of China(Grant No.51175461)Science Fund for Creative Research Groups of National Natural Science Foundation of China(Grant No.51221004)Program for Zhejiang Leading Team of S&T Innovation of China(Grant No.2009R50008)
文摘Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.
文摘基于数控系统绕刀具中心旋转(Rotation tool center point,RTCP)功能,R-test装置被用于多轴联动数控机床的联动精度检测与标定。该仪器通过三个直线位移传感器测量安装于主轴的球头球心空间位置,从而可测量机床多轴联动时的刀具中心点位置误差。在分析测量原理的基础上,提出最大测量空间和测量敏感度的两个用于评价测量性能的指标及相应的数值算法,得到一种R-test装置结构优化设计方法。在选择通用球头芯棒与长度计的情况下,通过约束分析得到测量杆安装圆直径、测量杆与基准面夹角两个关键尺寸的设计区间,利用蒙特卡罗法搜索得到这两个关键尺寸的最优解,完成结构优化设计。仿真表明,优化设计得到的R-test测量装置具有最佳的测量敏感度,可测区域大于半径为4 mm的球体,能满足实际测量精度和测量空间需要。