Effects of geometrical errors of guideways on the repeatability of positioning of linear axes of machine tools

This paper studies the effects of geometrical errors on the repeatability of positioning of linear axes, based on theoretical modeling and an experimental study. Firstly, this paper elaborates on the mechanism of repeatability of positioning that is affected by motion pose of moving part. Secondly, a mathematical model is proposed between the geometrical error and motion pose of the moving part, based on point-by-point recursion. Subsequently, the influence of geometrical errors on the repeatability of positioning of the linear axes is obtained based on GA (genetic algorithm). Finally, the effectiveness of the proposed model is validated experimentally, and an assembly method for improving the repeatability of positioning is proposed. The method can provide designers and/or field engineers with informative guidelines for improving the repeatability of positioning in the design, manufacturing, and assembly processes.