集成钣金优化排料系统

介绍了一个面向钣金集中下料生产模式的优化排样及数控切割编程系统ＡｕｔｏＣＵＴ。该系统集下料零件库的建立与管理、下料计划的自动生成、自动优化套排料、切割工艺设计、数控代码生成、模拟切割仿真及下料信息管理为一体。详细说明了ＡｕｔｏＣＵＴ系统的总体结构及运行流程、面向对象的数据结构和系统主要功能模块。最后给出了一个系统运行实例。     

矩形件排样优化的背包算法

根据矩形件排样的实际下料工艺要求，将一个二维排样问题转化为一个一维下料问题，并构造了一个利用背包问题解法的矩形件排样的近似优化算法。     

面向排样方式中零件种类数约束的一维优化下料方法

在一维下料方案的每种排样方式中,零件种类数决定后续切割加工过程中零件分类搬运的复杂度,进而影响下料全过程的加工成本。针对这类问题,以最小化原材料成本为主要优化目标的同时,兼顾考虑排样方式中零件种类数这一重要约束,建立了基于排样方式中零件种类数约束的一维多种原材料下料问题的数学模型,提出了一种面向排样方式中零件种类数约束的一维优化下料方法。采用基于排样方式中零件种类数约束的排样生成方法,获取多种原材料利用率高、同时满足排样方式中零件种类数约束的排样方式;以每种排样方式为基础,运用基于排样方式中零件种类数约束的顺序启发式算法生成多种优化下料方案,选取加工总成本最小的一种下料方案作为当前最优的下料方案。最后,通过实例验证了所提方法的可行性和有效性。     

满足“一刀切”约束的矩形件交互式排样系统

在诸如玻璃、木材等板型材的加工过程中,受制造过程和工艺的影响,其下料排样方案必须满足"一刀切"约束——"从矩形板材的一端,沿直线方向切割到另一端,将其分割成两个独立的矩形件"。下料排样时,通过智能优化软件和方法获得的下料排样方案仍有可能进行多次交互式调整,形成的排样方案仍然需要满足"一刀切"约束。针对这一需求,在拥有自主知识产权的排样系统的基础上,设计和开发了满足"一刀切"约束的矩形件交互式排样系统;开发了具有矩形件增、删、旋转和移动功能的交互式排样组件;定义了原材料有效利用率这一核心概念;提出了一种以切割线总路径为优化目标的切割线生成算法,该算法能自动生成排样方案的切割线,同时也能保证切割方案的"一刀切"约束。     

冲压件的智能排样

本文提出针对冲压件的一种基于知识的智能优化排样技术。把数学方法、子目标法、启发式搜索法及符号推理方法有机集成，协同求解。首次将制件下料技术的作业性作为排样的一种约束条件，探讨了智能优化排样的一些关键技术方法。     

基于ObjectARX的AutoCAD二次开发及优化下料应用

板材下料是有效开展生产的一项必要活动,AutoCAD是进行下料排样的计算机绘图和设计的常用软件,同时AutoCAD为用户提供了非常开放的二次开发环境.为此,对作为AutoCAD 2007二次开发工具的ObjectARX 2007进行了探讨和研究,分析了基于ObjectARX的AutoCAD二次开发的程序开发流程,详细阐述了进行板料优化排样程序开发的关键技术以及进行AutoCAD二次开发的命令订制方法,然后实施了以ObjectARX 2007为基础、以Visual Studio 2005为开发平台、以遗传算法为主要优化算法的下料程序开发,在AutoCAD中开发出自动排样的优化下料应用程序.最后,通过排样实例验证了本方法的实用性.     

分布式钣金CAD/CAM应用系统研究

为在网络环境下解决钣金展开设计、优化排样和数控下料等问题，研究并开发了分布式钣金CAD／CAM应用系统。系统以浏览器／服务器（B／S）模式实现展开计算和绘图，以客户／月艮务器（C／S）模式实现钣金件优化排样和处理数控代码；为实现系统分布式服务，应用了基于．NET框架的Web服务和代理技术；通过分布式产品数据共享，采用遗传算法或其他启发式算法，将展开设计结果进行优化排样；同时，通过数控工艺规划、前后置参数设置和数控代码仿真，获得数控加工代码。最后，以实例说明了钣金设计的网络化应用。     

基于填充算法的矩形件排样优化求解

针对矩形件优化排样问题，提出了一种将填充算法和遗传算法相结合的优化排样方法。该方法应用填充算法对遗传算法作预处理，使矩形件排样适用于“一刀切”的下料工艺，并克服了填充算法局部搜索的缺点，使搜索空间由一点扩大为多点，最终可获得总体最优的排样结果。算例表明，该优化排样算法运算速度快，具有广泛的适应性。     

基于变邻域人工蜂群算法的三维矩形箱体下料优化研究

相比一维、二维下料问题,三维空间下料优化问题存在零件规格种类多样、数量庞大、尺寸约束及工艺约束等多重因素限制,导致原材料利用率偏低的现象。为此,文中以三维矩形箱体为研究对象,建立了三维空间下料模型,基于变邻域人工蜂群三维矩形箱体下料算法及算法流程,设计了4种三维变邻域搜索策略：邻域交换、邻域顺序、邻域逆序及邻域正交,提出了5种三维解码方式：SCO,BCO,HO,WO和LO。试验结果表明：变邻域人工蜂群算法较人工蜂群算法在三维矩形箱体排样中有效提高了原坯料利用率及排样效率,排样方案更优、算法迭代时间更短、更加贴合生产实际,对解决制造业在三维空间下料效率与成本方面所面临的问题,具有很好的借鉴意义。     

面向可加工性的矩形件优化下料方法

针对多规格、大批量的矩形件优化下料问题,综合考虑原材料利用率高、切割加工路径短等优化目标,提出一种面向可加工性的矩形件优化下料方法。运用矩形原材料单方向余料最小化计算方法优选出候选板条,候选板条构造过程中的共边排样可用于共边切割,缩短了矩形原材料上局部切割加工路径;利用基于候选板条的连续启发式排样算法实现矩形原材料上优化排样设计,保证高原材料利用率的同时,简化了矩形原材料上切割加工总路径。通过实例验证了所提方法的可行性和有效性。     

基于数控切割工艺的单一零件优化排料

分析了在有限长、宽的整体板料上对单一零件优化排样的方法、步骤及其关键技术,总的目标是在单张板料上排放尽可能多的零件;提出了基于数控切割工艺的优化排样算法,给出并分析了算法运行实例.     

Effect of clearance on new shearing method with horizontal tool movement of 1100 aluminum sheet

Sheet metal cutting is a general metal forming process. A new cutting method has been invented for sheet metal by the authors. It has been named the MM-shearing method. There are several advantages in the method, for example small cutting force, beautiful cutting surface and no burrs on the cut surface. Moreover, the equipment used in the method is inexpensive. However, there are some important parameters to consider in the MM-shearing method, such as tool angle, clearance between the tool and die, sheet thickness, and cutting speed. In this paper, a series of experiments was carried out to examine the suitable clearance. The experimental material is 1100 aluminum sheet (Japanese Industrial Standard). The cutting force, ratio of sheared and fractured surfaces, inclination angle, burr height, roughness, and Vickers hardness of the cutting surface are examined corresponding to the clearance change. The principle and characteristics of the MM-shearing method are made clear in this paper in terms of the clearance between the tool and die.     

Optimal Predicted Fuzzy PI Gain Scheduling Controller of Constant Turning Force Systems with Fixed Metal Removal Rate

The dynamic behaviour of the turning process is nonlinear and time-varying owing to variations in cutting depth. This paper proposes an optimal predicted fuzzy PI gain scheduling controller to control the constant turning force (CTF) process with a fixed metal removal rate (MRR) under various cutting conditions. The predicted fuzzy PI gain scheduling control scheme consists of two parts: the fuzzy PI gain scheduling controller; and the grey predictor. First, the optimal parameters of both the grey predictor and the optimal PI gains corresponding to each desired cutting depth in the range of operation, are designed off-line by using the proposed optimal combined method, i.e. Taguchi–RGA method, which integrates the Taguchi method and a real-coded genetic algorithm (RGA). Then, before the parameters of both the grey predictor and the PI gains are scheduled on-line, by fuzzy inference in terms of the changes of cutting depth, the optimal set of triangular-type membership functions of the fuzzy inference mechanism for scheduling the parameters of both the grey predictor and the PI gains are also designed off-line by using the Taguchi–RGA method. Computer simulations are performed to verify the applicability of this optimal predicted fuzzy PI gain scheduling control scheme for controlling the CTF process with a fixed MRR under various cutting conditions. It is shown that such an optimal predicted fuzzy PI gain scheduling control scheme can achieve satisfactory performance and better results than those reported recently in the literature.     

基于顶点的冲裁零件排样系统

分析了冲裁件排样优化存在的问题 ,统一了材料利用率计算公式 ,提出基于顶点的一步平移优化算法。该算法可以有效减少计算量 ,较好地处理冲裁件图形圆弧、曲线线性化问题 ,有利于建立一个完整的冲裁件 CAD/CAM系统     

基于Pro/E的不规则钣金展开件的优化排样

介绍了遗传算法以及基于Pro/E的不规则形状钣金展开件的计算机优化排样,研究了排样中如何建立遗传算法的目标函数,如何实现编码、排样等优化过程,找到了运用遗传算法实现不规则形状钣金展开件优化排样的方法.     

基于Pro/E的不规则形状钣金展开件的优化排样

介绍了遗传算法以及基于Pro/E的不规则形状钣金展开件的计算机优化排样,研究了排样中如何建立遗传算法的目标函数,如何实现编码、排样实现等优化过程,找到了运用遗传算法实现不规则形状钣金展开件优化排样的方法。     

二维异形切割件优化排样的拟合算法

多种异形零件在钢板上的优化排样问题 ,实际上也可看作多边形(异形零件的外轮廓 )对多边形 (矩形 )的最优填充问题。从拼图游戏的启发构造了一个异形零件优化排样的拟合算法。用该算法对一些优化排样问题进行了计算 ,得到较为满意的结果     

Principle and Simulation of Fixture Configuration Design for Sheet Metal Assembly with Laser Welding, Part 1: Finite-Element Modelling and a Prediction and Correction Method

The quality of the stamping process has a direct effect on laser welded sheet metal assembly. The fixture plays an important role in the satisfactory metal fit-up that laser welding requires. The traditional "3-2-1" locating scheme will no longer suffice for the deformable laser sheet metal assembly process. Because of the often poor stamping quality, a complex die fixture has to be employed to meet the metal fit-up requirements. The die fixture corresponds to an "infinite-2-1" locating scheme where the tooling cost is very high and yet lacks flexibility. This limits the application of laser welding. In this paper, a new locating scheme with both total locating and direct locating for welds is proposed. A total locating scheme is used to locate the overall assembly, and a direct locating scheme is used to locate the weld location, which is critical for ensuring correct metal fit-up. A finite-element model and a prediction and correction method for the direct locator configuration are developed in this paper. A case study is used to show that the proposed method is effective for sheet metal assembly for laser welding.