Geometric calibration of a coordinate measuring machine using a laser tracking system

TLDR

Laser tracking systems use trilateration to measure 3‑D coordinates with high accuracy (≈0.3 µm over 600 mm) and are easy to set up. This study proposes a calibration method for a coordinate measuring machine using a laser tracking system. The method measures 3‑D coordinates with the laser tracker, then estimates 21 CMM parametric errors by comparing these coordinates with those obtained from the CMM. The estimated parametric errors matched those from a ball‑plate measurement, confirming the validity of the calibration system.

Abstract

This paper proposes a calibration method for a coordinate measuring machine (CMM) using a laser tracking system. The laser tracking system can measure three-dimensional coordinates based on the principle of trilateration with high accuracy and is easy to set up. The accuracy of length measurement of a single laser tracking interferometer (laser tracker) is about 0.3 µm over a length of 600 mm. In this study, we first measured 3D coordinates using the laser tracking system. Secondly, 21 geometric errors, namely, parametric errors of the CMM, were estimated by the comparison of the coordinates obtained by the laser tracking system and those obtained by the CMM. As a result, the estimated parametric errors agreed with those estimated by a ball plate measurement, which demonstrates the validity of the proposed calibration system.