| Modern manufacturing technology has put forward more exacting demand of speed and accuracy on Coordinate Measuring Machines (CMMs). High speed has become a new trend in CMMs technology. However, with the increase of speed of CMMs, the dynamic characteristic will be limited since dynamic errors will have a great impact on the measuring accuracy and act as a barrier to the measuring cycle time. This paper takes the main dynamic error source analysis on CMMs as the theoretical foundation to make research on dynamic error modeling of CMMs running with different velocity parameter and space position based on the CMMs dynamic characteristic analysis and testing. The method combining software with hardware is used to carry on the dynamic error correction to improve the dynamic measuring accuracy.The process of CMMs dynamic characteristic is studied experimentally under the touch-trigger probing pattern. The main dynamic error sources and composition of CMMs are identified and analyzed in detail. This paper makes research mainly on the influence which the probe system, machine structure and measuring system have on the dynamic error of CMMs. As for the probe system, the composition of its dynamic probing error is studied. A new concept of functional diameter of tip is put forward, the impact of the velocity parameters on the functional diameter is analyzed and the model of functional diameter is set in theory. As for the machine structure, the reason for its dynamic deformation is studied. The conversion between dynamic deformation and displacement error is modeled to validate the place-related characteristics of machine structure dynamic deformation both experimentally and theoretically. As for measuring system, the grating system scribing error, grating pairwise error, electronic system error, temperature error are studied, which pave the way for the development of the new grating measuring system.Develop the high-accuracy dynamic error data gathering contrast experiment system, use the double frequency laser interferometers as the high-accuracy dynamic measuring benchmark and measure the actual displacement of every axis of CMMs under different velocity, in real-time. Comparing the displacement with the reading of grating system, the difference is the single axis dynamic error. According to the ISO 230-2 standard to deal with the data, this paper analyzes the CMMs single axis stability and interrelated characteristic among axis under different velocity to realize the dynamic calibration which is more accurate than the static calibration.The dynamic measurement uncertainty of CMMs is evaluated with calibratedworkpieces according to the framework confirmed by "Guide to the expression of uncertain in measurement". At the same time, the dynamic measurement uncertainty of CMMs is evaluated using Monte Carlo method. By the contrast of the A type and B type evaluation, this method has access to the actual conditions.On the base of dynamic error sources analysis, modeling, the method of combining the software with hardware and the way of square sample stripe fit and shape-preserving function fit are used to make research on the dynamic error correction as weli as the way of setting up CMMs compositive dynamic error model under different measuring position and velocity, adopting dual linear returns. It is possible to smooth the impact of the grating signal subdivision circuit time-delay on the dynamic performance of CMMs when the grating measuring scale with the measuring precision of nanometer is studied based on two times Moire fringe principle.On the base of the research outcome of CMMs dynamic characteristic, this paper analyzes the international standard and national standard of CMMs performance evaluation and precision evaluation, especially ISO 10360-2, ISO 10360-5, ISO 15530-2.2 are studied and give some advices to the establishment or revision of relevant technological clauses.
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