基于D-H矩阵的柔性坐标测量机多测量模型研究

Research on multiple measurement models based on D-H matrix in flexible coordinate measuring machine

柔性坐标测量机使用灵活且携带方便等诸多优点,深受业界人士好评,但因其成本昂贵且精度不高而受到限制。在不增加柔性坐标测量机硬件成本的基础上,为了提高测量精度,提出了多测量模型方法。分析了单个测量模型的不足,研究了多测量模型的优越性。为了验证多测量模型的有效性,在实验中选取了标准量,给出了采样策略,进行了标定运算。结果表明,在同一采样区间,只带一个测量模型的柔性坐标测量机的测量误差为0.076 3 mm,而带多测量模型的柔性坐标测量机的测量误差为0.041 6 mm;在不同采样区间,只带一个测量模型的柔性坐标测量机的测量误差为0.128 4 mm,而带多测量模型的柔性坐标测量机的测量误差为0.052 3 mm。显然,多测量模型优于单个测量模型,这对于促进柔性坐标测量机的普及应用具有较大的理论价值和实际应用意义。

Flexible coordinate measuring machines （FCMM） with lots of advantages such as flexibility and easy to carry are deeply high praised by industry people. But the FCMM are limited because of high cost and low accuracy. The idea of multiple measurement models were proposed in order to improve flexible coordinate measuring machine＇ （FCMM） measurement accuracy on the basis of no increase in hardware cost. After analyzing the deficiency of one t model, the multiple measurement models were researched. The experiment standard was selected, then the sampling strategy was proposed and the calibration algorithm was given. The experiment results show that the measurement error sigma value from the FCMM with one measurement model is O. 0763 mm, and the error sigma value from multiple t models is O. 0416 mm in the same sampling area. But in the different sampling area, the multiple measurement models＇ t error is 0.0523 mm while the single measurement model＇ measurement error is 0. 1284 mm. Obviously, the multiple measurement models＇ way is far superior to the single measurement model＇s way. It is significant to promote FCMM widespread use in theory and practice.