This document provides methods for the determination of the contouring performance of numerically controlled machine tools.


This document specifies methods of testing and evaluating the bi-directional circular error, the mean bi-directional radial error, the circular error and the radial error of circular paths that are produced by the simultaneous movements of two linear axes.


This document also specifies methods of testing the deviations of the circular or constant radius trajectories generated by any combination of simultaneously controlled (coordinated) linear and rotary axes. The basic principle of these tests is to coordinate the multiple axes of motion (combination of rotary and linear axes) to keep the relative position between the tool and the workpiece constant.


This document describes differences between circular errors and radial errors (Annex A), influences of typical machine errors on circular paths executed with two linear axes (Annex B), precautions for test set-ups for circular tests with rotary axes (Annex C), an example of adjustment of diameter and contouring speed for circular tests (Annex D), and circular tests using feedback signal (Annex E).