Method for assessing measurement uncertainty of coordinate measuring machine

The invention discloses a method for assessing measurement uncertainty of a coordinate measuring machine. The method of avoiding the complex relation among error sources of the coronate measuring machine and unknown transmission rules between the error sources is adopted, the method of analyzing characteristic indexes of a measurement system of the coordinate measuring machine is adopted, the method and approach of verifying or obtaining corresponding system characteristic index values of the measurement system, an integral calibration method and a detail experiment scheme for obtaining a stability index and a reproducibility index of the coordinate measuring machine are designed, the influence degree of actual temperature in temperature compensation, a standard grating rule and a linear expansion coefficient of a tested workpiece on a measurement result is considered, and the relatively integral measurement uncertainty of the coordinate measuring machine is obtained through synthesis in the root of square sum.