Real-time laser tracker compensation of a 3-axis positioning system—dynamic accuracy characterization

The concept of integrating metrology systems into production processes has generated significant interest in industry due to its potential in reducing production time and defective parts. One of the most interesting methods of integrating metrology into production is the usage of external metrology systems to compensate machine tools and robots in real time. Continuing the work described in our previous paper of a prototype laser tracker-assisted 3-axis positioning system (Wang and Maropoulos Int J Adv Manuf Technol 69(1-4): 919-933, 2013), this paper describes experimental results of the dynamic path accuracy tests of the machine under real-time laser tracker compensation. Experiments show that the real-time corrections of the machine tool’s absolute volumetric error have significantly increased the dynamic path accuracy of the machine. This result is also validated by a ballbar acting as an independent measurement instrument, reducing the 95th percentile error from 60 μm to less than 10 μm, without any prior calibration or error mapping, showing that the proposed methods are feasible and can have very wide applications.