Uncertainty analysis in least-square fitting according to next generation of 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. Uncertainty estimation of measurement according to next generation of GPS can improve the reliability of the verification result. A method to estimate the uncertainty in the process of least-square fitting is proposed according to the requirements of next generation of GPS standard system. Based on the transparent box model given in ISO/TS 14253-2, the calculation equation of the uncertainty in the process of least-square fitting is deduced. The experimental result indicates that the method can not only assure the integrity of the verification result, but also improve the reliability of verification.