【作者】 张琦；

【导师】 廖达雄；

【作者基本信息】 西北工业大学 ， 机械设计及理论， 2005， 硕士

【摘要】 钣金件是机械产品中的一大类,从前对它的生产设计,从展开计算到下料排样,都是通过手工完成,虽然能取得较好的结果,但需要较长的周期,劳动强度大。随着CAD技术的日益成熟,论文成功地借助于CAD技术,运用软件工程的方法,针对生产实际中的常见钣金构件,开发出完整的钣金模块。 论文总结了图解法的利弊得失,以计算解析法为途径,运用现代信息技术,研究解决钣金件的自动展开计算、实现展开图绘制。按照工程实际经验将钣金件进行分类。选择了最具代表性的相贯钣金件,应用参数化的技术,建立数学模型,研究了精确绘制展开图的方法。 通过比较各种现有的排样方法,在详细讨论了排样技术的应用和研究现状,探讨了相关基本理论和技术的基础上,针对钣金件CAD模块要求的效率及实用性,重点讨论了矩形件排样算法,将人工智能领域中的遗传算法和模拟退火算法相结合,成功地应用到LFB[30]算法中,利用遗传模拟退火混合算法的全局优化搜索能力,得到了较LFB算法更优的排样结果。同时,还讨论了任意多边形零件的排样算法,并且对混合算法中的几个影响参数进行了简单的讨论,最终为钣余件排样系统的开发提供实用的算法。 论文合理架构模块软件结构,从底层开发,同时将OpenGL三维图形程序设计接口集成在模块中,实现了各种钣金构件的动态显示。更多还原

【Abstract】 Sheet metal is a large branch of mechanical products. In past designing and manufacture to sheet metal, from calculating and unfolding to nesting, had been finished by handwork. Though manual nesting adopted in production results in less trim loss, it is inefficient and manpower exhausting. Along with broad applications of the CAD technology, the paper makes use of it to designing CAD module, using the method of software engineering and contraposing frequent sheet metal in practice.Based on the analysis of sheet metal technology, the paper summarizes the advantages and disadvantages of diagrammatic method. The problems of automatic unfold-calculation and unfold-drawing are analyzed by modern information technology on the basis of calculation method. According to practical production, all kinds of sheet metal are classified. We select the most representative penetration component and establish its mathematical modeling, using parameter method. The solving method is also provided.Based on the review of research and application status of nesting problem, the paper discusses the related theory and technology. Through comparing and analyzing the needs of CAD module, including efficiency and practicability, paper focuses on rectangular nesting. In this paper simulated annealing algoritlim and genetic algorithm arc combined and integrated, and they are applied in LFB[30] algorithm successfully. when their optimizing and searching abilities in nesting are applied, we can get a better layout than LFB algorithm. Meanwhile, we discuss several iniluential parameters in the two algorithms and nesting algorithm of irregular parts, providing useful algorithm for CAD packing system.The CAD module’s software structure is constructed reasonably, and OpenGL graphics standard is integrated in it, realizing dynamic display of sheet metal.更多还原