Knowledge-based selection and sequencing of hole-making operations for prismatic parts

This paper describes the rule structure used to select the appropriate sequence of operations to produce various types of holes in 2 1/2D prismatic components manufactured on machining centres. Operation selection is based on forward chained rules coded in Prolog. A different rule priority sequence is applicable depending on the rule fired last. This solves the conflict resolution problem and ensures reasonably fast execution. Rule conditions perform feature extraction, feature size checks, operation suitability checks, tool suitability checks and processing status checks. Actions perform the processing operations and update the model through feature processing tags. The knowledge base implemented for hole-making was not obtained from a practical industrial environment. Nevertheless it does produce sensible plans and it is relatively easy to modify.     

基于特征信息和推理机制的齿轮类零件CAPP系统设计

结合齿轮零件的工艺特点,分析了实用型CAPP系统的功能要求,构建出了系统的总体结构框架,结合系统开发功能以及齿轮类零件的工艺特点,决定采用基于齿轮特征描述法与齿轮分类编码描述法的这两种方法来描述齿轮信息,建立齿轮信息模型,并且采用基于知识推理和齿轮工艺模板的决策机制自动进行工艺设计,自动生成新齿轮的工艺路线,从而使得系统的实用性进一步增强,同时还具有一定智能性以及柔性;系统的人机交互功能,进一步增强了系统的实用性、可靠性以及柔性.     

CAPP中箱体类零件信息描述的一种新方法

本文提出了一种C APP中面向箱体类零件的信息描述方法,它通过方位描述、轮廓描述、形面描述等多个处理过程,来满足(A PP对零件信息描述的要求。最后本文介绍了以这种描述方法为依据所开发的交互式零件信息输入系统。     

Towards an intelligent approach for CMM inspection planning of prismatic parts

This paper presents a model of prismatic parts (PPs) inspection planning on CMMs, in terms of an intelligent concept of inspection planning. The developed model is composed of Inspection Feature Construction, Sampling Strategy, Probe Accessibility Analysis, Automated Collision-Free Generation, and Probe Path Planning. In this model, the simulation of a measuring probe path is based on three algorithms: Algorithm for Measurement Points Distribution, Algorithm for Collision Avoidance, and Algorithm for Probe Path Planning. The simulation output is a measuring protocol for CMM UMM500. An experiment was performed on two PPs that have been produced for the purpose of this research. The inspection results show that all tolerances for both PPs are within the specified limits. The proposed model presents a novel approach for the automatic inspection and a basis for the development of an integrated, intelligent concept of inspection planning. The advantages of this approach imply the reduction of preparation time due to an automatic generation of a measuring protocol, a possibility for the optimisation of measuring probe path, i.e. the reduction of a time needed for the actual measurement and analysis of a workpiece, and an automatic configuration of measuring probes.     

基于Pro/E面向数控加工的箱体零件CAPP系统

以Pro/E为开发平台,开发一种面向数控加工的箱体零件CAPP系统,解决CAD信息向CAPP系统的转换,实现从设计特征到制造特征的自动识别与提取和CAD/CAPP的集成.     

基于特征造型的轴类零件设计系统

以特征造型思想为基础,用VB 6.0和Access 2003为开发工具对Autodesk Inventor进行二次开发,开发出轴类零件设计系统。系统采用模块化结构,主要阐述了信息输入及处理模块、特征造型模块、工程图绘制模块等主要模块及其实现方法。系统能够对不同形状的轴类零件进行计算机辅助设计并生成工程图,具有记录建模过程并实现人机交互功能的特点,显著的提高了设计效率。     

CAPP系统面向对象工艺信息建模体系研究

以对象类树、对象关系图、对象类(属性、方法)描述表为基础,分析CAPP面向对象工艺信息模型的建立过程,提出进行企业工艺分析与信息建模的规范化方法,形成企业面向对象工艺信息建模体系.     

汽车回转类零件CAPP系统的研究

介绍大批量生产环境下的汽车回转类零件CAPP RPCAP系统的结构、功能及特点 ,重点讨论零件信息输入、工艺规程生成等关键技术问题。该系统可实现工序内容和工序图的自动生成     

An IGES post-processor for interfacing CAD and CAPP of 2 1/2D prismatic parts

An IGES post-processor is presented, written in FORTRAN-77, to extract from an IGES file all information that an automatic process planning program needs, derive new information when necessary and formalise it as PROLOG facts. The processor deals with wire frame models and drawings. Its various modules are described and considerations about its design are discussed, associated with the IGES specification philosophy and pre-processor implementations. Analogous approaches from other processor designs are reviewed.     

数控工艺优化设计系统的研发与应用

系统以特征技术为基础,将CAPP技术引入到数控编程中,在三维CAD系统UG中,通过API直接开发CAPP系统,实现了CAD系统与CAPP系统的内嵌式集成,以及CAD系统到CAPP系统的数据信息内容的自动传递和CAPP数控加工工艺的自动生成,提高了数控编程的效率和质量。     

换热器CAPP系统开放式结构的研究与实现

针对换热器CAPP系统和开放式程序结构,提出基于数据库的换热器CAPP系统总体结构,建立基于数据库的CAPP系统,实现数据库表结构设计和维护的开放性,应用程序在图形绘制、数据输入、打印输出和制造工序编制等方面都具有良好的开放性。     

基于特征设计的回转体零件CAD/CAPP集成系统的研究与开发

介绍了所开发的一种基于特征设计的回转体零件 CAD/ CAPP集成系统。系统采用基于特征设计的零件信息模型 ,实现零件的信息共享 ,使 CAPP决策过程可直接应用 CAD输出的信息。在此基础上 ,通过建立基于数据库的工艺决策模型 ,实现了工艺过程的生成和输出     

CAPP的刀具自动选择系统

提出了一种工艺特征建模和刀具建模的方法 ,给出了CAPP刀具系统的总体结构。描述了基于工艺和刀具定义的刀具选择的一般过程 ,并在此基础上 ,实现了工艺流程和工序内容的参数化分类 ,实现了刀具的自动选择     

CAPP中轴类零件工序图自动生成技术研究

工序图是工艺设计结果的图形表达形式,其绘制的自动化程度低,是CAPP技术进步的主要瓶颈之一。针对运用AutoLISP二次开发工具以及数据库技术实现工序图自动绘制过程中,计算机对各个图元的自动识别、编辑和操作的要求,提出了一种轴类零件工序图自动生成的新方法,在参数化绘制预处理零件图的过程中,通过给各个图元重新命名完成了零件几何特征信息的存储,并将零件加工工艺信息代码化,采用逆序修改特征的方法实现了轴类零件工序图生成的自动化。研究结果表明,由计算机生成的一套工序图可以准确地反映出零件在从毛坯到成品的制造过程中,零件的形状和尺寸变化情况以及加工工序中的各个工艺要素,对其他类型零件的工序图自动生成也具有一定的参考价值。     

利用用户定义特征实现的冲压CAD/CAPP集成系统

提出了利用CAD系统的用户定义特征实现面向CAPP的特征设计的方法，在归纳定义常用冲压特征的基础上，建立了冲压特征信息模型，介绍了用Visual C 6．0在参数化三维特征CAD软件平台上开发的冲压CAPP系统，实际应用证明，用户定义特征是在商品化CAD系统中实现集成化CAD／CAPP系统的一种有效方法。     

Analytic Hierarchy Process Based Decision Modelling in CAPP Development Tools

Process planning decision modelling is a main barrier in the research on CAPP development tools, and also a bottleneck hampering the process of pragmatisation and commercialis-ation of CAPP. Analytic hierarchy process (AHP), is a mathematical decision modelling tool for solving complicated process planning decision problems by decomposition, determination and synthesis. AHP can deal with universal modelling of process planning decision-making, which is difficult to describe quantitatively, by integrating quantitative analysis with qualitat-ive analysis.     

An integrated intelligent process planning system for prismatic parts using PC-based CAD and CAM software packages

Traditional machining process planning relies heavily on human decision making and manual calculations. The utilisation of CAM software and computers to aid machining reduces errors and planning time. A fully integrated planning system using CAD and CAM software would further increase the efficiency of process planning. The goal of this research is the automation of machining process planning for prismatic parts by integrating Autocad and Mastercam software packages using the Autolisp programming language and artificial intelligence techniques. Using only a 3D representation of the prismatic part geometry drawn in Autocad as input, the integrated system will be capable of producing NC code for the machining of the part with minimal human intervention. This system would greatly enhance the productivity of machining process planning.     

自定义加工特征的船用柴油机箱体件CAD/CAPP/CAM集成系统

为解决当前船用柴油机箱体类零件设计制造集成度不高、信息传递不顺畅等问题,提出基于自定义加工特征的方法来构建此类零件的CAD/CAPP/CAM集成系统。该方法依据成组技术和知识工程的原理,根据其形状特点和刀具轨迹形式将零件的各个加工特征进行分类,构建自定义加工特征库。在加工特征表述中,使用属性和标注进行表示,可实现基于加工特征的集成模式下的工艺决策和数控编程。采用自定义加工特征方法能够大大减少人工交互操作,提高工艺决策和数控编程的准确性和自动化程度。     

CIMS环境下基于范例的综合式CAPP系统的体系结构研究

体系结构是系统工艺设计的基础。一个良好的体系结构有利于顺利和有序地进行工艺设计开发工作。本文重点介绍了集成化环境下基于范例的综合式 CAPP系统的工作原理和体系结构 ,在上述研究的基础上 ,针对具体应用环境开发了一个箱体类零件的集成化综合式 CAPP系统     

焊接板材特征拼装CAPP开发环境的研究与实践

简要介绍了CAPP系统的开发及原理,以集成环境下支座类、箱体类等焊接零件CAPP系统的开发为例,重点讨论了焊接类零件CAPP系统在集成环境下的开发及实践的问题。