Annotated bibliography on computer-aided process planning

Computer-aided process planning (CAPP) has attracted great research interest for the last two decades and a large volume of material has been published on the subject. With the introduction of contemporary manufacturing philosophies such as concurrent engineering, agile manufacturing and the like, the research in process planning has been gradually transformed into an inter-disciplinary and multi-faceted problem domain. By compiling, classifying and annotating a sample of articles published in the last few years, the paper provides a logical organisation of the literature on process planning. Some rudimentary analysis is included based on observations made during the compilation process.     

Algorithms for computer-aided generative process planning

Process planning is the function within a manufacturing facility that establishes the machining processes and parameters to be used so as to convert a piece-part from its initial form to the final form predetermined on an engineering drawing. Computer-aided process planning (CAPP) has become a major focus of manufacturing automation as it forms the interface between computer-aided design (CAD) and computer-aided manufacturing (CAM). Issues in CAPP include part representation, process selection, alternative process-plan generation, intermediate surface and tolerance determination, and operation sequencing. This paper focuses on quantitative models for determining cutting dimensions and tolerances for intermediate surfaces, and on a heuristic for sequencing cutting operations.     

Workpiece modelling for computer-aided process planning

Different concepts can be applied for representation of workpiece data for CAPP. Instead of waiting for future standards, a practical method is required, which can be used for actual workpieces or those that have been designed in the past by using already existing CAD systems. Therefore, for developing the CAPP system an approach has been chosen which consists of (1) a structure and geometry recognition of the workpiece and (2) an editor for technological data.This paper shows the main characteristics of a workpiece model which can be used for process planning. The results of an analysis of workpieces in industry give an overview of the topological relationships between geometrical elements which is an essential part of workpiece modelling for future design and planning systems. Also, a link between the workpiece model and the CAPP system is presented and briefly discussed.     

基于知识的计算机辅助导管加工工艺设计

为了满足导管加工质量和成形精度的要求,提出了一个基于知识的导管加工工艺设计系统。该系统采用面向对象的技术定义了导管加工通用约束、企业生产条件约束和用户导管质量需求约束,给出了导管弯曲加工工艺知识的面向对象表达。由于采用了以用户导管质量需求为目标的驱动的推理机制,实现了导管弯曲加工工艺的自动生成。     

计算机辅助工艺规划综述(二)

通过对计算机辅助工艺规划（CAPP）系统发展过程进行总结，指出CAPP的发展方向及企业成功实施该系统的模式选择。     

Tool paths and cutting technology in computer-aided process planning

This paper reports on the development of a module to calculate automatically tool paths and cutting conditions for metal cutting operations. Process planning must select correct cutting conditions to minimise disturbances on the shop floor owing to tooling problems. Tool path and cutting condition algorithms to generate reliable NC programs have been designed. The algorithms have been implemented in the framework of a generative computer-aided process planning system, called PART. Geometrical requirements to avoid chipping of cutting teeth are considered in tool-path calculation. The cutting conditions are calculated using metal cutting process models. A method has been developed to calculate cutting forces for milling operations based on experimental data of cutting forces in turning. In the process models, various constraints of the machine tool, cutting tool, and the workpiece are considered.     

CAPP系统中基于AHP的排序优先级研究

CAPP是CAD/CAM集成的桥梁和纽带,由于工艺决策问题约束复杂、随机性强,排序准则的确定需要根据具体的加工环境和加工对象来制定。为了便于工艺路线的自动生成,本文采用AHP(层次规划法),一种数学决策模型,进行排序优先级的确定。首先介绍了AHP模型及其构造算法,然后,以回转体零件在数控加工中心上的工步排序方案决策为例,用Visual Ba-sic编制程序,验证了基于AHP的柔性工艺优先排序决策方法的可行性。     

A computer-aided system for sustainability assessment for the die-casting process planning

The sustainability assessment of a product's manufacturing using a life cycle assessment tool utilizes the average sustainability performance of the manufacturing process. Because of using an average of sustainability performance, the crucial information related to manufacturing is lost. Therefore, such an assessment cannot be used to assess and compare the sustainability of a part made using different process plans. In this paper, we propose a new systematic approach for sustainability assessment of the die-casting process planning. A computer-aided system named Sustainability Assessor for Die-casting is presented. Here, we discuss the details of the architecture and working of the proposed system. We assess sustainability using three sustainability indicators, namely, energy use, solid waste, and carbon emissions. The proposed system is verified by comparing results with the actual data measured from the shop floor. The developed system is beneficial for sustainability assessment comparing different plans alongside material properties, ultimately helping the die-casting industry to reduce the carbon emissions and material waste, besides improving energy efficiency.     

Multi-agent system for distributed computer-aided process planning problem in e-manufacturing environment

This paper deals with the multi-agent system for distributed computer-aided process planning problem. The proposed architecture consists of three autonomous agents (Global Manager Agent, Design Agent, and Optimization Agent) capable of communicating to each other through eXtensible Markup Language (XML). In contrast to the traditional process planning model, a new paradigm incorporating fixture cost has been conceptualized. Optimization agent is facilitated by the virtues of DNA computing and identifies the optimal/near optimal process plan with the help of available resources. Furthermore, in order to investigate the efficacy of the developed architecture, the manufacturing of a prismatic part having 23 operations has been simulated and solved accordingly. Results obtained reveal the superiority of the proposed architecture.     

A geometrical approach to computer-aided process planning for computer-controlled machine tools

This paper documents part of a research program which has been under way at the CIM Centre at Swinburne University of Technology since 1989. The purpose of the research program was to develop an open-architecture machine tool control system and then to see how that system could be used to change the distribution of traditional manufacturing design, planning and control functions. This paper examines one part of that research program and focuses on a methodology which could prove to be useful in the machine tool selection, cutter selection and cutter path generation phases of process planning for cutting operations on workpieces in computer-controlled machine tools.It is suggested that a configuration space transform be used for each cutter/machine tool combination to find the volume that the combination could remove from the uncut workpiece without removing any of the material that will form the final workpiece. A method of comparing these volumes from different combinations is then outlined. The output of this method is a reasonable sequence of machine tools and cutters. Path planning can then be carried out for each of the chosen combinations using a method similar to the one used to find the possible volume to be removed.Possible implementation techniques, and their limitations on existing computer hardware, are discussed and the most promising of these are identified, based upon some properties of configuration space transforms.     

An object-oriented hierarchical case representation of automotive panels in a computer-aided process planning system

Case-based reasoning (CBR) has a promising application prospect in computer-aided process planning (CAPP) for automotive panels. How to effectively represent and organize the abundant information in the cases has a crucial impact on the effectiveness of case retrieval and adaptation. This paper presents an object-oriented hierarchical case representation scheme for automotive panels in process planning. The scheme is based on an extended object model and case object model which are extensions of the object model in object-oriented modelling technology. Information in cases is divided into three kinds and each kind is represented by different kinds of classes. Accordingly the representation scheme has four layers and different kinds of classes have different functionalities. A car fender case is presented as an example.     

Framework of a computer-aided short-run SPC planning system

Statistical process control (SPC) is recognized as a technique to achieve cost-effective quality control through continuous manufacturing process improvement. But with growing demand for small-batch and high-variety products in the current dynamic market, the involved manufacturing processes are becoming more complex, variable, and flexible, which are not suitable for implementing SPC in the traditional way. Hence, short-run SPC is applied instead. Planning is a critical phase in the implementation of short-run SPC, which includes the formation of part families and the determination of corresponding data collection. To ensure homogeneity of the family members, this paper addresses preliminary analysis on the characteristics and applications of pertinent factors, and statistical analysis for SPC-based part family formation. To improve the efficiency of SPC planning and the adaptation for computer-integrated manufacturing, a framework for a computer-aided short-run SPC planning system is proposed using group technology classification and coding concepts. This invokes a 29-digit hybrid code appended to the Opitz coding scheme. Further, a supportive database is also proposed to facilitate coding information retrieval and system updating. A case study is shown with data collected from injection-mold manufacturing, which typically involves small-batch processes.     

面向工艺设计的制造过程建模

基于工艺设计对产品制造成本、质量和效率的重要影响,提出了一种基于工艺设计的制造过程建模方法,以通过对过程模型的仿真,预测、分析和优化工艺设计效果。基于对制造过程的特征分析,采用面向对象的方法,首先将制造过程定义为一组成对象,并划分为制造活动、过程控制和制造资源3类成分对象,建立了制造过程类结构模型和动态过程模型。分别定义了工序类、制造资源类和过程控制类的类结构模型,以及各类对象的方法和属性。基于这些模型开发了一种计算机辅助工艺设计系统,可快速、自动地构建工艺设计定义的制造过程模型,并对过程参数（成本、时间）、切削加工、工件物流进行计算和仿真。     

基于工艺元信息的装配工艺过程设计

为实现复杂产品装配工艺过程的快速没计,通过装配结构与工艺特征分析,提出了装配连接元与装配工艺元的元信息概念,并扩展至可装配组件与工艺元组.采用面向对象技术表达装配工艺元与装配工艺元组的组成,分析了装配连接元与装配工艺元的属性规则映射.提出了一种实现装配工艺元设计的三阶段法,给出基于工艺元的装配工艺过程设计流程,有效提高了装配工艺过程设计的效率.通过分析单级齿轮减速器装配工艺设计实例,并开发了装配工艺过程设计原型系统模块,验证了所提方法的可行性.     

Integer programming approach to process planning

In this paper an integer programming approach to the process planning problem is presented. Although the presented approach can be applied to any type of manufacturing system, some implications of the flexible manufacturing environment on process planning models are discussed. The relationship between the process planning models and the FMS software environment is shown. Algorithms for solving the developed models as well as computational results are discussed.     

Rule-based process planning by grouping features

A macro-level CAPP system is proposed to plan the complicated mechanical prismatic parts efficiently. The system creates the efficient machining sequence of the features in a part by analyzing the feature information. Because the planning with the individual features is very complicated, feature groups are formed for effective planning using the nested relations of the features of a part, and special feature groups are determined for sequencing. The process plan is generated based on the sequences of the feature groups and features. When multiple machines are required, efficient machine assignment is performed. A series of heuristic rules are developed to accomplish it.     

基于加工基元的制造过程规划研究

针对现有CAM系统的自动工艺规划功能弱,难以进行有效工艺决策的缺陷,根据数控工艺的特点,提出了加工基元的概念,并在此基础上建立了产品制造信息模型,进行了制造过程规划优化研究,完善了CAM系统中的工艺规划功能。并采用XML标准对制造过程规划文件CNCML文件进行了描述,为面向网蓐化制造的CAD／CAPP／CAM系统集成提供了有效的实现方珐。     

QFD based optimal process quality planning

Process quality planning is an important activity of quality assurance. It aims to determine manufacturing processes with appropriate process capability to produce product characteristics. Quality function deployment (QFD) is a powerful tool for quality planning, which starts with identifying customer needs and ends with determining process plans. However, most studies on quality planning by QFD are limited to the product planning stage. The approach to process quality planning through QFD has rarely been discussed. This paper adopts the optimal QFD model and further develops it for process quality planning. By incorporating an empirical capability function for process elements, a composite process capability index (CCp) is presented to reflect the overall process quality level. Constraints including technical feasibility, correlations among process elements, project budget and development time are considered. A case study of the numerical control (NC) machining process quality for a thin-walled complex window frame of airship is given to illustrate how the proposed model can be effectively applied by process quality team to determine the optimal target level of process elements concerning with resources utilization .