ScienceDirect - Computer-Aided Design : Geometric mouldability analysis by geometric reasoning and fuzzy decision making

Computer-Aided Design
Volume 36, Issue 1, January 2004, Pages 37-50

Font Size:

Abstract - selected

E-mail Article

Add to my Quick Links

Bookmark and share in 2collab (opens in new window)

Request permission to reuse this article

Cited By in Scopus (4)

Related Articles in ScienceDirect

There are no related articles for this article.

View Record in Scopus

doi:10.1016/S0010-4485(03)00067-8

Geometric mouldability analysis by geometric reasoning and fuzzy decision making

Zhou-Ping Yin ^a, Han Ding ^b, Han-Xiong Li ^,^,^c and You-Lun Xiong ^a

^a School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, People's Republic of China ^b School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai, People's Republic of China ^c Department of MEEM, Faculty of Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, People's Republic of China

Revised 26 March 2003;

accepted 28 March 2003. ;

Available online 22 April 2003.

References and further reading may be available for this article. To view references and further reading you must purchase this article.

Abstract

This paper presents a methodology for mouldability analysis by finding the optimal cavity design scheme (CDS) based on manufacturing and cost considerations using part geometry, where a CDS refers to a combination of the parting direction, parting line (PL), and undercut features (UF). The methodology takes advantage of geometric reasoning and fuzzy evaluation, and consists of two main stages: (1) generating all possible design alternatives, and (2) choosing the best alternative. In the first stage, after recognizing the potential UF from the given part, a spherical arrangement is constructed by partitioning the unit direction sphere using outward normals of the part's surfaces with the property that each cell in this arrangement has a unique combination of PL and UF set. Thus all design alternatives can be identified in O(ml²) time by visiting the cells in a certain order and updating the PL and UF set incrementally, where m and l are the number of the part's convex and overall surfaces, respectively. In the second stage, the fuzzy multiple attribute decision-making model is employed to choose the optimal scheme from the set of design alternatives with respect to a set of criteria related to the number and volume of undercuts, flatness of the PL, draw depth, and draft angle. This model allows designers to describe their preferences on different criteria in imprecise linguistic statements. Finally, the case studies show that the proposed methodology is very effective in finding the optimal CDS for the molded part and the final results conform to human designers' experience.

Author Keywords: Geometric mouldability; Geometric reasoning; Fuzzy multiple attribute decision-making; Design for mouldability; Mold design