A method to estimate the stiffness and damping of the aerostatics slideways of coordinate measuring machine(CMM)for the compensation of acceleration errors is proposed. The vibration equations of CMM are established from the framework model of CMM and transformed into the form of the frequency response functions(FRFs)of first order systems
where the identified parameters are contained. The FRFs are tested and then the stiffness and damping parameters can be identified with Bode diagram rather than Levy method. Modal analysis is performed on CMM system after the identification of stiffness and damping parameters. The acceleration errors are forecasted with modal superposition method. Experiments indicate that the cross-correlation coefficient between the measured errors and the forecasted errors at CMM probe tip is over 0.7
which verifies the effectiveness and reliability of the proposed method.
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references
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