Motion Error of V-Type Roller Linear Guides Considering Geometric Errors of the Guide Rails

V-type roller linear guides can achieve extremely high motion accuracy through precision design and machining; however, theoretical research and methodologies in this field remain limited. This paper proposes a computational method for estimating the motion errors of V-type roller linear guides and establishes a four-degree-of-freedom error model that accounts for guide rail yaw errors, guide rail pitch errors, variations in roller positions, and the contact states of rollers. The effects of the error wavelength ratio, load, and number of roller rows on the motion error of a single V-type roller linear guide are investigated, and the mechanisms and characteristics of the error averaging effect are analyzed. The motion error characteristics of a double V-type roller linear guide are also discussed. Finally, the proposed model is applied to the development and motion error estimation of a double V-type roller linear guide for a grating ruling engine. The straightness of the carriage in the X and Y directions over a 600 mm travel distance reached 0.62 μm and 0.48 μm, respectively. Furthermore, a high-precision echelle diffraction grating with a wavefront PV of 0.21λ was fabricated. These results further validate the proposed model and provide guidance for the manufacturing error allocation and precision design of V-type roller linear guides.