AN EFFICIENT METHOD FOR IDENTIFICATION OF MOTION ERROR SOURCES FROM CIRCULAR TEST-RESULTS IN NC MACHINES

This paper proposes an efficient method for the identification of moti on error sources involved in NC machines by the circular test, which i s often used in estimating the motion accuracy of NC machines. The mot ion error signal from the circular test is classified into two fundame ntal patterns: a nondirectional error pattern (the mean of the clockwi se and counterclockwise test signals); and a directional error pattern (deviation of clockwise or counterclockwise test signals from a nondi rectional error pattern). The present paper proposes two identificatio n schemes: the frequency analysis method and the weighted residual met hod. The frequency analysis method is used for identifying error sourc es of the nondirectional error pattern and the weighted residual metho d is used for identifying error sources of the directional error patte rn. A menu-driven, user-oriented computer program is written to realiz e the entire proposed identification procedure. The proposed identific ation method is applied to two typical circular test results in order to verify its effectiveness. (C) 1997 Published by Elsevier Science Lt d.