柴油机箱体类零件计算机辅助工艺设计系统

本文论述了一种创成式计算机辅助柴油机箱体类零件数控工艺设计系统(BCAPP)。该系统首先用表面要素法建立零件加工表面的工艺信息数据文件,经原始数据优化排序模块对加工顺序进行优化排序,数控工艺生成模块读取优化排序后的工艺信息生成工艺文件,然后经排版打印模块可很快排印出非常令人满意的、符合工厂生产实际的、高质量的工艺文件。工序图由工序图绘制模块生成可直接由绘图机绘出。     

柴油机箱体类零件计算机辅助工艺设计系统

本文论述了一种创成式计算机辅助柴油机箱体类零件数控工艺设计系统(BCAPP)。该系统首先用表面要素法建立零件加工表面的工艺信息数据文件,经原始数据优化排序模块对加工顺序进行优化排序,数控工艺生成模块读取优化排序后的工艺信息生成工艺文件,然后经排版打印模块可很快排印出非常令人满意的、符合工厂生产实际的、高质量的工艺文件。工序图由工序图绘制模块生成可直接由绘图机绘出。     

基于SCHEMA的STEP-NC数控编程系统研究

基于新的STEP-NC数控接口标准,对STEP-NC的SCHEMA进行解析,研究STEP-NC数控程序的生成方法。分析和研究了STEP-NC数控程序,探讨Part21文件的格式和部分关键信息的生成方法,研究SCHEMA到STEP-NC数控程序的映射方法。基于SCHEMA开发了STEP-NC数控编程系统,该系统采用开放式模块设计,分为信息提取与特征识别模块、工艺规划模块、STEP-NC文件生成模块。该系统可进行自动特征识别,经人机交互方式进行工艺规划,最终生成STEP-NC数控程序。     

加工铲齿铣刀成形砂轮的计算机辅助设计

在分析铲齿铣刀加工工艺及工件、铣刀、砂轮三者关系的基础上，介绍了在AutoCAD R14环境下，利用内嵌的AutoLISP语言，二次开发的铲齿成形铣刀铲磨用的成形砂轮截形CAD系统。系统主要包括工作端面廓形输入模块、铣刀廓形生成模块、铲磨用成形砂轮截形生成模块、铲磨干涉检验模块及用于修整成形砂轮的NC指令生成模块等。     

基于Mastercam X软件投影加工方法应用

以一典型的投影加工实例重点介绍MastercamX软件在投影加工模块中的详细应用.包括加工工艺分析与参数设置、刀路的生成、后置处理生成NC程序等.     

船用柴油机箱体零件CAD／CAPP／CAM集成系统设计和开发

本文介绍一个适用于船用柴油机箱体零件的ＣＡＤ／ＣＡＰＰ／ＣＡＭ集成系统的设计和开发。它由特征造型、工艺生成和排印模块、ＮＣ刀轨生成、ＮＣ后置和ＮＣ模拟模块组成，整个集成以一个特殊设计的零件特征造型文件为基础。生成的工艺文件可进入Ｆｏｘｂａｃｅ数据库供ＣＡＭ其他用途。生成ＮＣ程序适用三个不同类型的ＮＣ控制器，并能进行平面和立体模拟加工过程。整个系统在ＨＰ工作站及其网络中进行。     

基于结构移植的产品模块成本估算技术

为提高客户需求响应速度,增加产品成本估算精度,提出了基于结构移植的产品模块成本估算技术。对产品模块进行了多层次解析,建立了模块结构体模型。通过基于规则的多层次检索获取产品模块移植结构体,以结构体移植的修正方式生成虚拟模块。根据移植结构体与工序之间的信息映射创成虚拟模块工艺路线,实现工艺成本估算,合成原材料成本与工艺成本得到产品虚拟模块成本,为产品快速报价提供依据。该技术在电梯产品报价系统中得到了实际应用,提高了电梯产品成本估算速度与精度。     

基于ObjectARX的箱体零件单元形面工艺的生成

结合KDCAPP系统的单元形面加工工艺生成模块 ,介绍用ObjectARX技术与ADO技术开发基于AutoCAD的数据库的方法。     

船用柴油相箱体零件CAD／CAPP／CAM集成系统设计和开发

本文介绍一个适用于船用于柴油相箱体零件的ＣＡＤ／ＣＡＰＰ／ＣＡＭ集成系统的设计和开发。它由特征造型、工艺生成和排印模块、ＮＣ刀轨生成、ＮＣ后置和ＮＣ模拟模块组成，整个集成以一个特殊设计的零件特征造型文件为基础。生成的工艺文件可进入Ｆｏｘｂａｃｅ数据库供ＣＡＭ其他用途。生成ＮＣ程序适用三个不同类型的ＮＣ控制器，并能进行平面和立体模拟加工过程。整个系统在ＨＰ工作站及网络中进行。     

基于UG的叶轮数控加工及仿真

根据叶轮的形状和特点,通过UG8.0建立了叶轮的三维模型,制定了数控加工工艺,讨论了加工工艺参数,分别生成了基于可变轮廓铣和叶轮模块刀具轨迹,校验正确后通过后处理生成实际可用的五轴数控程序。     

A tradeoff analysis between process plan selection and cell formation in cellular manufacturing

In this paper, an algorithm to evaluate the tradeoff between conflicting objectives in process plan selection and cell formation is developed. Consideration of the minimisation of intercell material movement in cellular manufacturing is necessary but not in itself sufficient to produce a system for which the total work content is minimised. Solving the process plan selection and the cell formation problem for all possible alternative process plans is a time-consuming task, and therefore not economically justifiable. The algorithm is illustrated through the use of a sample problem that shows how it is possible to create a cell using the algorithm presented in this paper.     

[工艺规划与装配线平衡]两阶段混合算法求解集成工艺规划与调度问题

提出了求解集成式工艺规划与车间调度问题的两阶段混合算法。在工艺规划阶段,使用遗传算法为每个工件生成可选的近优工艺路线集,动态地为车间调度阶段输入已确定的工艺路线;在车间调度阶段,使用蜜蜂交配优化算法快速寻优,设计了蜂王婚飞的流程以保证算法的全局搜索能力,构建了基于不同邻域结构的工蜂培育幼蜂局部搜索策略。使用基准测试集对提出的方法进行验证,并与现有算法进行对比,计算结果证明了提出方法的有效性。     

A collaborative manufacturing execution platform for space product development

Space product development enterprise has the feature of single piece or small batch productions, in which the product manufacturing process changes frequently, key components need process preparation, and production scheduling problem is often complicated. According to the development process of space products, a collaborative platform under network-based manufacturing environment for space products development is proposed in this paper. The main structure of the platform and the cooperation process between each application modules are proposed. Moreover, a kind of dynamic job shop scheduling algorithm is presented. The algorithm is used to realize rapid response and adjust manufacturing plan when production or process plan has changed. Finally, a prototype system that supports space product manufacturing process management is developed and a case study is presented to demonstrate the efficiency of proposed algorithm.     

一种面向机械车间柔性工艺路线的加工任务节能调度方法*

大量研究表明机械车间消耗了大量能量,因此降低机械车间的能耗是实现可持续制造的策略之一。现有机械车间节能调度研究主要针对给定的或者具有部分柔性的工艺路线,缺乏对机械车间任务工艺路线多柔性的节能调度研究。针对机械车间任务柔性工艺路线对机械车间调度能耗的影响特性,提出一种面向机械车间柔性工艺路线的节能调度方法。首先,分析了面向机械车间柔性工艺路线的加工任务调度的能耗特性;基于此,构建了节能调度模型,该模型是以任务加工总能耗、加工完成时间、机床负载为目标。进一步提出了一种改进的Q学习算法对该模型进行求解获得其Pareto解。最后通过案例验证了提出模型的节能效果及算法的可行性。     

Advanced lumber manufacturing model for increasing yield in sawmills using GPR-based defect detection system

This paper proposes an advanced lumber manufacturing model for real-time process control in saw mills in order to increase the yield of high value defect-free lumber. Detecting subsurface defects by scanning canted logs and generating a process plan to cut the logs can increase the yield of high-grade lumber in a saw mill industry. The defect detection process is performed using the ground-penetrating radar (GPR) system. More recently, a defect detection algorithm was developed to process GPR scanned data using the MATLAB? software. This research uses the distance and depth coordinates generated by the defect detection algorithm to develop the process plan that generates a cutting sequence for the resaw machine. The process plan is in the form of an algorithm written in MATLAB? with a simple user interface. The generated cutting sequence was validated by comparing to the conventional sawing sequence, where the operator of the resaw machine randomly performs the cutting of boards. An increase in the yield (in terms of dollar value) of about 27% was noticed using the GPR-based detection system which can map interior defects prior to sawing the log and enable an optimal sawing pattern.     

基于特征工艺重用的箱体零件工艺规划研究

针对箱体类零件结构的复杂性 ,提出了基于特征工艺重用的工艺变型设计方法 ,由基于实例的方案重用技术生成零件特征的加工链 ,将基因遗传 /禁忌混合算法应用于加工工序的排序 ,从而获得了零件合理、优化的工艺方案     

基于分布式并行遗传算法的大规模板材套料优化模型

通过描述分布式计算与并行遗传算法的概念有其相互关系，阐述了利用分布式并行遗传算法进行板材套料的原因。提出并分析了在企业分布式计算环境中进行板材套料优化的计算过程、计算环境及其技术支撑系统。     

Integration of Process Planning and Scheduling Using Simulation Based Genetic Algorithms

Process planning and scheduling are traditionally regarded as separate tasks performed sequentially; but, if the two tasks are performed concurrently, greater performance and higher productivity of a manufacturing system can be achieved. Although several workers have addressed the process plan selection problem in recent years, their main approaches are to select process plans from plan alternatives by taking into account the similarities among process plans of the parts. In this paper, we propose a new approach to the integration of process planning and scheduling using simulation based genetic algorithms. A simulation module computes performance measures based on process plan combinations instead of process plan alternatives and those measures are fed into a genetic algorithm in order to improve the solution quality until the scheduling objectives are satisfied. Computational experiments show that the proposed method reduces significantly scheduling objectives such as makespan and lateness.     

A Branch and Bound Algorithm Based Process-Planning System for Plastic Injection Mould Bases

This paper describes the use of artificial intelligence in the process planning of plastic injection mould bases. The computer- aided process-planning system, developed for IMOLD? will extract and identify the operations required for machining. These operations are considered together with their precedence constraints and the available machines before the process plan for the mould base plate is generated. The process plan is optimised by a branch and bound based algorithm. Overall machining time has been proposed as the objective function for optimisation. The ability of this algorithm to search intelli-gently for a feasible optimised solution is illustrated by an industrial case study. A brief comparison with a genetic algor-ithm based process planning system is also made. The result of this development will allow users to optimise process plans easily for any given mould base, with options to suit dynamic changes on the manufacturing shop floor.     

GA-based synthesis approach for machining scheme selection and operation sequencing optimization for prismatic parts

To obtain global and near-global optimal process plans based on the combinations of different machining schemes selected from each feature, a genetic algorithm-based synthesis approach for machining scheme selection and operation sequencing optimization is proposed. The memberships derived from the fuzzy logic neural network (FL-NN), which contains the membership function of each machining operation to batch size, are presented to determine the priorities of alternative machining operations for each feature. After all alternative machining schemes for each feature are generated, their memberships are obtained by calculation. The proposed approach contains the outer iteration and nested genetic algorithm (GA). In an outer iteration, one machining scheme for each feature is selected by using the roulette wheel approach or highest membership approach in terms of its membership first, and then the corresponding operation precedence constraints are generated automatically. These constraints, which can be modified freely in different outer iterations, are then used in a constraints adjustment algorithm to ensure the feasibility of process plan candidates generated in GA. After that, GA obtains an optimal process plan candidate. At last, the global and near-global optimal process plans are obtained by comparing the optimal process plan candidates in the whole outer iteration. The proposed approach is experimentally validated through a case study.