Sculptured surface-oriented machining error synthesis modeling for five-axis machine tool accuracy design optimization

Abstract

Abstract:Customer-oriented design is very important for machine tool manufacturers to win competition in the market. Mechanical parts with complicated sculptured surface are widely utilized in mechanical systems such as automobiles, aircrafts and wind turbines, and they are often machined by five-axis machine tools with high precision requirements. However traditional machine tool design has not accounted for the varied machining errors in producing complex sculptured surface, which leads to inferior performance. To address this challenge, a novel machining error synthesis model is proposed in this paper for accuracy optimization in designing general five-axis machine tools used for making various sculptured surfaces. The new synthesis model bridges between surface machining profile error and the machine tool accuracy, and it is constructed by integrating a generic machine tool volumetric error model and two new surface machining error production models. The synthesis model is then applied as a constraint in machine tool accuracy design optimization. Also a tolerance-cost function is formulated to construct the objective function, and a meta-heuristic algorithm is developed to implement the optimization. All these modeling and optimization methods are validated by one case study.

Optimal Design Method for Static Precision of Heavy-Duty Vertical Machining Center Based on Gravity Deformation Error Modelling

“…The upper limit of the gravity deformation error of the relevant components determined by the static precision assignment of each motion axis can be expressed by Equation (19).…”

“…Li and Liu analyzed the sensitivity of each error source of the machine tool by the proposed generalized sensitivity index [18]. Li et al used a heuristic algorithm to allocate the errors of the five-axis machine tool [19]. Zhang et al proposed a precision design method considering manufacturing cost and reliability [20].…”

Accuracy analysis and synthesis of asymmetric parallel mechanism based on Sobol-QMC

“…Accuracy synthesis is a reverse solution process based on accuracy analysis. [29][30][31] For a 4-DOF parallel mechanism, Huang et al 32 distinguished the uncompensated errors by error model. These errors were compensated by accuracy synthesis.…”