三坐标测量机长度测量不确定度评定

Evaluation of uncertainty in length measurement with three coordinate measuring machine

三坐标测量机在应用时,通常得到的只是被测参数的估计值,而没有给出具体测量任务的测量不确定度。从长度测量的最小二乘估计模型出发,参照ISO测量不确定度表示指南,对影响不确定度估计的一些因素加以分析,推导不确定度计算的传递链函数,并且与蒙特卡罗模拟方法的不确定度评定结果相比较,验证了此模型的准确性。此模型可推广应用于三坐标测量机各种测量任务的不确定度评定中,从而实现三坐标测量机测量值和不确定度评定的完整报告,提高三坐标测量机测量结果的准确度和可信度。

CMM in application usually just give the estimated value of the parameters and can not give the corresponding measurement uncertainty.According to the model of least-square evolution of length measurement and the ISO Guide to the Expression of uncertainty in Measurement（GUM）,analyses the main measuring errors and uncertainty estimation delivery chain function is deduced.At last Monte—Carlo method is used to evaluate the uncertainty.