Research On High Accuracy Measurement And Separation Of 3-D CMM'S Dimensional Error

3-D coordinate measuring machine (3-D CMM) is applied in manufacture and measure widely. And the error measurement of CMM appears especially significant, because higher and higher precision is demanded. The error source of CMM is complex, and the current main research is its geometric error. In the paper, 21 items of geometric error are measured accurately, simply and fast with the 2-D laser interferometer and four quadrants photo detector. The measurement gets rid of measuring so many lines and several diagonal lines in linear displacement method, and also solves the question that error measure of large-scale CMM can not be measured with 1-D ball array and ball plate conveniently.In the measurement, random subspace OXYZ is chosen in measure space of CMM, and 9 straight lines parallel with coordinate axes in XOY, XOZ and YOZ plane are measured with 2-D laser interferometer. At the same time straightness error is measured by four quadrants photo detector, and then all the 21 items of geometric error is measured, including position error, straightness error, angular error and verticality error. So error of each point in the entire measure space can be calculated with mathematical model of semirigid body. The emulation software compiled by LabVIEW simulates the actual measure process, and carries on analysis and procession with the data to confirm the feasibility of the measurement.According to high accuracy error measure of CMM, error compensation can enhances accuracy of CMM further, and then CMM appears more application in modern industry and measure.