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

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 is constructed by integrating a generic machine tool volumetric error model and two new surface machining error production models, and it bridges between the surface machining profile error and the machine tool accuracy. The synthesis model is then applied as a constraint in machine tool accuracy design optimization. A cost-tolerance function is formulated to construct the objective function, and a heuristic algorithm is developed to implement the optimization. These modeling and optimization methods are validated by one case study.