基于草图的产品三维CAD模型概念设计推送方法

Conceptual Design Push Method of 3D CAD Models Based on Sketches

针对产品广义设计过程不同阶段的需求特点以及加快概念设计向详细设计的转换,提出了一种基于草图的产品三维CAD模型概念设计推送方法。首先,用户根据概念设计需求,利用基于CAD几何造型平台开发的手绘图板绘制三视草图;然后,对手绘三视草图和模型库中CAD模型投影得到的三视投影图提取特征信息,采用2. 5D球面调和描述子来表示草图特征信息;最后,利用Euclidean距离计算通过球面调和变换获得的图形特征向量之间的距离,从而实现模型之间的相似性评价,并在农业机械装备模型库中完成算法的验证。实验结果表明,该方法能够有效帮助用户快速地具象化查询意图,发掘与产品概念设计阶段意图最相符的三维模型,并将相似性设计资源推送给设计人员,进而参考、启发和扩展设计思维,实现产品概念设计的快速响应。

According to the requirements characteristics at different stages of generalized product design process and acceleration of the transformation from conceptual design to detailed design,a method of conceptual design push of 3D CAD model of products based on sketch was proposed.First of all,according to the conceptual design requirements,a three-view sketch was drawn by using a hand drawing board based on CAD geometric modeling platform.Then,feature information was extracted from hand-drawn three-view sketch and three-view projection diagram of CAD model projection in model library,and the 2.5D spherical harmonic descriptor was used to represent the sketch feature information.Finally,Euclidean distance was used to calculate the distance of the graph feature vectors obtained by spherical harmonic transformation to realize the similarity evaluation between models and verify the algorithm in the agricultural machinery equipment model database.The experimental results showed that the method can effectively help users visualize the query intention quickly,explore the 3D model which was most consistent with the intention of product conceptual design stage,and push the similar design resources to designers,so as to reference,inspire and expand the design thinking and realize the rapid response of product conceptual design.