The Detection of NC Machine Geometric Accuracy Based on the Principle of Multiple-Time GPS

Abstract

This paper presents a measurement method of NC machine geometric accuracy. The principle is that a laser tracker is used to collect a lot of target point coordinates on four different locations around the machine during the machine spindle moving. A redundant equations could be established through target point coordinates,then the exact location of each target point coordinates could be determined by the principles of GPS positioning.Through the target point coordinates,the geometric error of machine could be separated. The method has fast measuring speed and low cost.Moreover the measurement precision is higher than direct measurement only using one laser tracker because the GPS positioning principle is used to avoid the angle measurment of laser tracker.