Estimation of uncertainty in form error CMM measurement according to new GPS standard system

Next generation of Geometrical Product Specifications (GPS) is the foundation of the technology standards and metrology specifications of mechanical and electric products. GPS estimation of uncertainty in CMM measurement can improve the reliability of the verification result. In this paper, a method to estimate the uncertainty in form error CMM measurement is proposed according to the requirements of new GPS standard system. Based on the transparent box model given in ISO/TS 14253-2, the calculation equation of the uncertainty in form error CMM measurement is deduced. And the decision rule based on the conformance uncertainty is adopted to decide whether the form error can be accepted or not. The experimental result indicates that the method can not only assure the integrity of the verification result, but also improve the reliability of verification.