Dynamic measurement accuracy evaluation of coordinate measuring machines

The coordinate measuring machine (CMM) is one of the most flexible and vers atile inspection machines in the manufacturing industry. Used around the wo rld, the CMM has become a symbol of industrialization. However, there is st ill no reliable method for evaluating the accuracy of a CMM. The current co mmonly used method-the static evaluation method-may result in an incorrect assessment owing to the very dynamic nature of the CMM. In order to evaluate CMM dynamic accuracy, in this paper an error separatio n method for dynamic measuring data is presented to obtain their accuracy e valuation indices. Referring to international evaluating principles of meas urement uncertainty, this method was derived through the analysis of dynami c measuring data and dynamic measuring error. To verify the validity of the proposed method, the dynamic accuracy of a CMM was evaluated and was found to be much better than that of the current static evaluation method.