A study on tolerance design of machine tool components based on shape generation motions

Abstract

The kinematic motion deviations of the five-axis machining centers are deeply influenced by the geometric deviations of the components, such as guide-ways and bearings. A systematic design method is required for specifying suitable geometric tolerances of the guide-ways, in order to improve the kinematic motion deviations of five-axis machining centers. The objective of the present research is to establish a computer-aided design system for specifying a suitable set of the geometric tolerances of the guide-ways considering the trade-off between the requirements on the kinematic motion deviations and the ease of the manufacturing processes. A mathematical model was proposed in the previous papers to represent the standard deviations of the shape generation motions, based on the tolerance values of the guide-ways of the five-axis machining centers. A systematic method is proposed here, by applying an optimization method, to determine a suitable set of the tolerance values of all the guide-ways under the constraints on the kinematic motion deviations between the tools and the workpieces. The method is applied to some design problems of the geometric tolerances of the guide-ways included in the five-axis machining centers.

A study on tolerances design of parallel link robots based on mathematical models

“…(1) Kinematic Motion Deviations of Rotational Joints 4 by 4 homogeneous transformation matrices are applied to represent the kinematic motions and their deviations in the previous and present research works (Satonaka et al 2005), (Satonaka et al 2007), (Satonaka et al 2008), (Sugimura et al, 2012), (Takahashi et al, 2014), (Takematsu, et al, 2016). The kinematic motions at the rotational joints shown in Fig.…”

“…However, most of the research works have not yet considered the statistical analysis of the three-dimentional tolerances. A set of research works have been carried out to represent and to analyze the three-dimentional kinematic motion deviations of the machine tools based on the statistical characteristics of the geometiric tolerances of the machine tools (Satonaka et al 2005), (Satonaka et al 2007), (Satonaka et al 2008), (Sugimura et al, 2012), (Takahashi et al, 2014), (Takematsu, et al, 2016). The methods proposed in the previous papers are applicable to the machine products other than the machine tools.…”

“…(17) in the design process of the tolerance valuses. The design process are proposed in the previous paper (Takematsu, et al, 2016), and summarized in the next secsion.…”