A novel method for uncertainty evaluation of roundness errors based on geometrical product specification

摘要

Roundness of circular and cylindrical parts can greatly affect assembly accuracy. It is essential to establish a proper method for evaluation roundness error to ensure achieving accurate assessment. According to the evaluation principle of roundness error and the uncertainty theory, a novel method for the uncertainty evaluation of roundness errors is proposed based on the new generation geometrical product specification (GPS). Under the condition of minimum zone, the mathematical model of roundness error and the optimal objective function were developed. Particle Swarm Optimization (PSO) algorithm was used to search for the optimal solution of roundness error. The uncertainties of each of coefficients which influenced the roundness error and of transfer coefficient were calculated in order to get the uncertainty of roundness error. The evaluation results accord with requirements of new generation GPS standard and indicate that this method can assure the integrity and veracity of evaluation.