Abstract: The mathematic model of the design problem is established to design the characteristic curves of the complex sculpture surface steel frames based on geometric constraint,and the mathematic problem is solved.The breadth-first search algorithm is adopted to deal with the feature curves in order to eliminate useless branches and isolated graphs.The problem of ambiguity in selecting is avoided by setting the reserved reference plane.The complex curves are converted to multi-line which could be used by the equipment.And the conversion error analysis function is designed.The program-modeling method is used to develop the design system and all the functions are validated by actual model.

Key words: sculpture surface, surface steel frame, characteristic curves, breadth-first search, geometric constraint, multi-line, program-modeling

摘要： 为解决复杂雕塑型面钢架的特征曲线快速设计问题,基于几何约束建立设计问题的数学模型,并完成了数学问题的求解;针对特征曲线分支和多孤立图形的问题,采用广度优先遍历算法对特征曲线进行处理,剔除无用分支和孤立图形。通过设置保留参考平面来避免选择歧义的问题,解决了型面分块问题。采用复杂曲线转换为多段线的方法来解决复杂曲线加工设备不能处理的问题,并设计了转换精度分析方法。设计系统采用程序法建模的方式来进行设计系统的开发,并通过实例验证了设计系统的功能。

关键词: 复杂雕塑型面, 型面钢架, 特征曲线, 广度优先遍历, 几何约束, 多段线, 程序法建模