Experimental Evaluation of Leica T-Mac Angular Accuracy

Abstract

The Tracker Machine (T-Mac) control sensor from Leica (Hexagon Manufacturing Intelligence, North Kingstown, RI) is a unique, dynamic, large-volume six degree of freedom (6DOF) metrology system widely used for scanning, probing, and calibration, as well as real-time control of machine tools and robots. It is a hybrid metrology system utilizing both laser tracking and active photogrammetry, where the laser tracker system provides the 3DOF position and the photogrammetry system provides 3DOF orientation. Although there exist international standards for evaluating the accuracy of laser trackers, there appears to be a lack of literature on the assessment of angular accuracy of this type of instrument. This article presents an experimental method of evaluating the T-Mac angular accuracy throughout its measurement range using a precision rotary table. The article describes the setup of the experiment and measurement comparisons at different ranges and orientations of the T-Mac.