Noncontact interferometric technique for calibration of coordinate measuring machines

Abstract

A novel calibration technique of 3D coordinate measuring machines using noncontact interferometric technique is described and a design of a new construction of length standards (ball bar, ball plate) for calibration of 3D coordinate measuring machines is proposed. The proposed optical technique uses as a sensor a small spherointerferometer for the determination of the coordinates of the center of the ball bar. Formulas are derived, which make possible to calculate an accuracy of the centre position of the spherical surface that is used for the length standard. An analysis of the proposed method is performed based on the third order aberration theory. The proposed technique can be used as a practical tool for a simple, rapid check of a positioning performance of 3D measuring machines.