An Approach for the Evaluation of Sphericity Error and Its Uncertainty

The verification uncertainty theory in new generation geometrical product specification (GPS) has been applied in the whole process of geometrical product specification and verification. According to the uncertainty theory, a novel method for the uncertainty evaluation of sphericity errors was proposed. The association operator in new generation GPS was applied. The mathematical model of the sphericity error and the optimal objective function were developed under the condition of minimum zone. Particle swarm optimization (PSO) algorithm was used to search for the optimal solution of sphericity error. The coefficients of the correlation element and propagation of uncertainty were calculated so that the sphericity error and the uncertainty of the result can be obtained. The evaluation results are accurate and consistent with requirements of a new generation GPS standard. It also indicates that this method can improve the integrity and veracity of verification