一種基于三角面片法線方向設計復雜異形模型自由曲面分型面的方法

董香平1，樊慶文1，蔣汶莙2，周明聰1，熊良胤1，裴宏亮*,1

（1.四川大學 機械工程學院，四川 成都 610065；2.中國工程物理研究院 總體工程研究所，四川 綿陽 621900）

摘要：提出一種基于復雜異形體模型三角面片法線方向設計異形分型面的方法，利用數字化三維模型構建三角面片模型的半邊數據結構；計算所有三角面片法線方向，確定最佳拔模方向；根據三角面片法線方向與最佳拔模方向的空間關系，將各三角面片聚類并確定異形分型線，沿最佳拔模方向進行平移，得到復雜模型的異形分型模具。以人體胸骨模型的模具設計為例，計算人體胸骨模型的最佳拔模方向，設計異形分型線，獲得胸骨模型的異形分型模具，并將該方法應用于人體其他器官模型。實驗證明，該方法適應性強，能夠快速確定異形分型面，具有重要的實用價值。

關鍵詞：復雜異形模型；三角面片；分型線；最佳拔模方向

中圖分類號：TG76 文獻標志碼：A doi：10.3969/j.issn.1006-0316.2022.05.001

文章編號：1006-0316 (2022) 05-0001-07

A Method of Designing Free-Form Parting Surface of Complex Special-Shaped Model Based on the Normal Direction of Triangular Patch

DONG Xiangping1，FAN Qingwen1，JIANG Wenjun2，ZHOU Mingcong1，XIONG Liangyin1，PEI Hongliang1

( 1.School of Mechanical Engineering, Sichuan University, Chengdu 610065, China; 2.Institute of System Engineering, China Academy of Engineering Physics, Mianyang 621900, China )

Abstract：A method of designing a special-shaped parting surface based on the normal direction of the triangular patch of a complex special-shaped model is proposed. The digital three-dimensional model is used to construct the half-edge data structure of the triangular patch model. The normal direction of all the triangular faces is calculated and the best draft is determined. According to the spatial relationship between the normal direction of the triangular patch and the best draft direction, we clustered the triangular patches and determined the special-shaped parting line, and then translated along the best draft direction to obtain the special-shaped part of the complex model mold. Taking the mold design of the human sternum model as an example, we calculated the best draft direction of the human sternum model, designed the special-shaped fractal line, obtained the special-shaped fractal mold of the sternum model, and applied this method to other human organ models. Experiments have proved that the method has strong adaptability. It can quickly determine the special-shaped fractal surface, which is of important value in practice.

Key words：complex special-shaped model；triangular patch；parting line；optimum draft direction

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收稿日期：2021-11-17

基金項目：四川省苗子工程項目（2020JDRC0029）；四川省重點研發項目（22ZDYF2983）

作者簡介：董香平（1996－），男，四川廣元人，碩士研究生，主要研究方向為計算幾何、計算機視覺、模式識別，E-mail：522797562@qq.com。*通訊作者：裴宏亮（1997－），男，甘肅岷縣人，博士研究生，主要研究方向為計算機圖形學、人工智能，E-mail：peihongliang@hotmail.com。