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摘要: 为了最大限度地利用船模曲面的三族型线, 使造型结果蕴涵更多的船模曲面的设计信息, 分析了各类曲面造型方法构建船模曲面的不同效果, 提出了面向数控加工的船模曲面三维造型的过曲线网格法, 以一艘实际双艉船模曲面为例, 研究了过曲线网格法实现船模曲面三维造型的关键技术: 局部区域包容方案与分片造型方案, 利用UG/OpenGrip开发了船模曲面三维造型模块。对于双艉船模曲面的制造, 采用传统的手工放样的制作方法至少需要30 d, 而采用四坐标船模曲面数控加工系统只需6 h就可以完成船模曲面98%的加工量, 并且经测量验证: 船模曲面的尺寸精度、形位精度和光顺效果, 较传统的制作方法均有显著提高, 满足船模曲面数控加工的要求。Abstract: In order to farthest make use of three sets of molded lines of ship model surface (SMS) so that SMS modeling contains more design information, SMS modeling effects realized by many kinds of surface modeling methods based on UG were analyzed, a modeling method of through curve mesh (TCM) for numerical machining of SMS was proposed, the key technologies of SMS 3-D modeling by TCM were studied, which are local region enveloping and surface partition, and SMS 3D modeling module was developed by UG/OpenGrip.It needs at least 30 d for traditional handcrafting manufacturing method to finish twin-skeg SMS, however, only 6 h is needed for 4-axis SMS NC (numerical control) machining system to finish 98% of the workload, the dimension precision, geometrical precision and fairing effect of SMS realized by the method are better than those realized by the traditional method, so the 3-D modeling precision of SMS realized by TCM can fully satisfy the requirements of numerical control machining, and is feasible.
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Key words:
- ship engineering /
- ship model surface /
- 3-D modeling /
- through curve mesh
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