并联机械手冗余最小误差识别及校准实验验证

Identification of Redundant Minimum Error of Parallel Manipulator andExperimental Verification

针对并联机械手的运动精度,以某三自由度主轴头为例,提出一种基于最小误差模型的运动精度校准方法。通过消除冗余几何源误差,建立包含最少几何源误差的最小误差模型,采用蒙特卡罗法模拟进行几何源误差灵敏度分析,研究各几何源误差对终端精度的相对影响。在此基础上提出粗校准和精校准相结合的分层辨识策略,以实现并联机械手的精度校准。通过校准实验测试表明:所提出的校准方法能够大幅降低并联机械手的终端误差,验证了所提校准方法的有效性。

Aimed at the motion accuracy of redundant driven parallel manipulator,and a three degree of freedom spindle head taken as an example,a motion accuracy calibration method based on minimum error model is proposed.The redundant geometric source error is eliminated to establish the minimum error model including the minimum geometric source error,and the sensitivity of geometric source error is analyzed by Monte Carlo simulation to study the relative impact of each geometric source error on terminal accuracy.On this basis,a hierarchical identification strategy combining coarse calibration and fine calibration is proposed to realize the accuracy calibration of redundant driven parallel manipulator.The calibration experiments show that the proposed calibration method can greatly reduce the terminal error of redundant driven parallel manipulator,and verify the effectiveness of the method.