Evaluation of roundness error uncertainty by a Bayesian dynamic model

摘要

The majority of existing measurement and evaluation methods of geometric tolerance of products are for the static processes and thus are not suitable for problems of measurement information traceability, dynamic management and control of measurement process. In this paper, a Bayesian dynamic model for evaluating the uncertainty of roundness error is proposed. The least square error evaluation is carried out first based on coordinate measuring machine (CMM) information, and then the probability density function (PDF) of roundness error is described by the maximum entropy principle. By using the prior distribution of Bayesian theory to calculate the synthetic posterior distribution, the measurement information is fused, and then the uncertainty is evaluated dynamically. Through digital experiment and test analysis of bearing outer ring, and compared with ISO standard method, the results show that Bayesian dynamic model can correctly and effectively evaluate the uncertainty dynamically. The overall estimation process is stable. (C) 2020 Elsevier Ltd. All rights reserved.