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Computer-aided process planning-A critical review of recent developments and future trends

For the past three decades, computer-aided process planning (CAPP) has attracted a large amount of research interest. A huge volume of literature has been published on this subject. Today, CAPP research faces new challenges owing to the dynamic markets and business globalisation. Thus, there is an urgent need to ascertain the current status and identify future trends of CAPP. Covering articles published on the subjects of CAPP in the past 10 years or so, this article aims to provide an up-to-date review of the CAPP research works, a critical analysis of journals that publish CAPP research works, and an understanding of the future direction in the field. First, general information is provided on CAPP. The past reviews are summarised. Discussions about the recent CAPP research are presented in a number of categories, i.e. feature-based technologies, knowledge-based systems, artificial neural networks, genetic algorithms, fuzzy set theory and fuzzy logic, Petri nets, agent-based technology, Internet-based technology, STEP-compliant CAPP and other emerging technologies. Research on some specific aspects of CAPP is also provided. Discussions and analysis of the methods are then presented based on the data gathered from the Elseviers Scopus abstract and citation database. The concepts of ‘Subject Strength’ of a journal and ‘technology impact factor’ are introduced and used for discussions based on the publication data. The former is used to gauge the level of focus of a journal on a particular research subject/domain, whereas the latter is used to assess the level of impact of a particular technology, in terms of citation counts. Finally, a discussion on the future development is presented.

STEP-compliant NC research: the search for intelligent CAD/CAPP/CAM/CNC integration

Since the first generation of Numerically Controlled (NC) machine tools was developed in the 1950s, there have been many developments which make todays NC machines completely unrecognizable from their early ancestors. Further developments, however, are now being significantly limited by the current programming language (ISO6983 or RS274D) that has been supporting NC manufacture since day one. Today a new standard, informally known as STEP-NC, is being used as the basis for development of the next generation of Computer Numerically Controlled (CNC) controller. This new standard is ISO 14649 and ISO 10303 AP 238. This standard gives CAM and CNC vendors the opportunity to integrate the capabilities of CAD/CAM systems with a new breed of intelligent CNC controllers, which have bi-directional communication of information representing standardized geometric and manufacturing data. This paper presents a comprehensive review of STEP-NC developments for a range of CNC processes. These developments include some major projects collaborated at the international level as well as those carried out by different groups of researchers in countries such as Germany, Switzerland, UK, Korea, USA and New Zealand. This paper also tries to portray a futuristic view of STEP-NC applications for CAD, CAPP, CAM and CNC integration, identifies the issues and challenges for STEP-NC, and provides a vision of a STEP-NC-compliant process chain supported by a product and manufacturing model.

Manufacturing Service Management in Cloud Manufacturing: Overview and Future Research Directions

As a new service-oriented manufacturing paradigm, cloud manufacturing (CMfg) has experienced rapid development in the past five years. The research on its theories, key technologies, developments, and applications still keeps attracting attentions from more and more researchers. One of the most important issues to its improvements and quality of service (QoS) is the manufacturing service management (MSM). CMfg aims to realize the full-scale sharing, free circulation and transaction, and on-demand use of various manufacturing resource and capabilities in the form of manufacturing service. Without the effective operation and technical support of MSM, the implementation of CMfg and its aim cannot be achieved. It is therefore necessary to summarize the existing works and technologies on MSM in CMfg. This paper first provides a brief overview of CMfg and then focuses on the problem of MSM in CMfg from the service lifecycle perspective. The advances on MSM technology from eleven aspects are investigated and summarized. Finally, future research directions are identified and discussed. It is evident that the future MSM in CMfg is closely related to Internet of things (IoT), big data, and cloud computing.

Survey paper: Computer-Aided Inspection Planning-The state of the art

Computer-Aided Inspection Planning (CAIP) has been a research topic for the past 25 years. Most of the CAIP systems were developed for Coordinate Measuring Machines (CMMs). The authors reviewed these CAIP systems and categorized them into two groups: tolerance-driven and geometry-based CAIP systems. Compared with CMMs, On-Machine Inspection (OMI) systems provide direct inspection in manufacturing and quality control, which is vital for automated production. Since the early 1990s, new CAIP systems have been developed for OMI systems. New technologies were developed in improving CAIP. New product data standards such as STEP and STEP-NC have been developed to provide standardized and comprehensive data models for machining and inspections. This paper systematically reviewed the recent development of these CAIP systems, new standard and technologies. A new notion of integrating the machining and inspection process planning based on the STEP-NC standard is discussed.

Recent development of knowledge-based systems, methods and tools for One-of-a-Kind Production

In recent years, product knowledge has played increasingly significant roles in new product development process especially in the development of One-of-a-Kind products. Although knowledge-based systems (KBSs) have been proposed to support product development activities and new knowledge modelling methodologies have been developed, they are still far from complete. This area has become attractive to many researchers and as a result, many new knowledge-based systems, methods and tools have been developed. However, to the best of our knowledge, knowledge-based systems for product development have not been systematically reviewed, compared and summarized. This paper provides a comprehensive review on the recent development of KBS, methods and tools in supporting rapid product development. In the paper, the relevant technologies for modelling, managing and representing knowledge are investigated and reviewed systematically for better understanding their characteristics. The focus is placed on knowledge-based systems that support product development, and how product knowledge is identified, captured, represented and reused during the processes of One-of-a-Kind product development. The limitations and the future trend of KBS are presented in terms of how they can help One-of-a-Kind Production (OKP) companies.

Advanced Design and Manufacturing Based on STEP

The globalisation of manufacturing has led to a need for a common language which can be used throughout the entire product development life cycle. Advanced Design and Manufacturing Based on STEP discusses the most successful of the proposed solutions the Standard for Exchange of Product model, or STEP. STEP aims to provide a complete computer-interpretable product data format, so that users can integrate business and technical data to support all aspects of the product development cycle, e.g., design, analysis, manufacturing, sales and customer services. Of particular significance is the publication of STEP-NC as an extension of STEP to NC, utilising the feature-based concept for CNC machining purposes. The contributors to this volume are based in some of the worlds leading national research institutes and universities and enterprises. The twenty chapters cover recent research results, and a range of STEP and STEP-NC application case studies from the fields of design and manufacturing.Advanced Design and Manufacturing Based on STEP will serve as a useful compilation for researchers and students in advanced manufacturing technologies and manufacturing information systems. It offers a range of literature concerning the use of STEP in both design and manufacturing domains.

An Adaptable CNC System based on STEP-NC and Function Blocks

Superior to G-code, STEP-NC is a new data model for computer numerical control (CNC). It provides rich information for CNC machine tools. This high-level information contains feature-based data. Unlike G-code that describes ‘how-to-do’, STEP-NC models ‘what-to-do’ at the task level in terms of features and ‘Workingsteps’. In the absence of a STEP-NC controller, there is a need for a system which can work with STEP-NC data and at the same time interface with the existing CNC machine tools. This paper describes such a system. This system acts like a ‘front-end’ for the current CNC controllers, giving these machine tools a ‘Plug-and-Play’ feature. The core of the system is the mapping mechanism which accepts STEP-NC data and translates it into the type of G-code that a specific controller can understand. The key to the mapping mechanism is the use of function block (IEC 61499) technology. This gives the system robustness and modularity.

Framework of a product lifecycle costing system

Todays competitive business environment imposes new challenges to manufacturing companies. For these companies to survive in this environment, implementing product lifecycle management (PLM) technologies with an emphasis on cost control is one valid approach. PLM is a strategic business approach that applies a consistent set of business solutions to help manufacturing companies manage all the activities related to a product in an integrated way across the lifecycle from customer need to product recycling and disposal. Product lifecycle cost is an important measure for PLM implementation. It can help track and analyze the financial information of activities associated with each phase of a products lifecycle. The paper presents a framework of the product lifecycle costing system for supporting decision making, especially the decision making at very early stages of a product lifecycle. It can be used as a design support tool to help new product development. A number of methodologies and tools are developed in the system. The case based reasoning method is used to quickly build a new product model. The costs of product development processes related to the new product are calculated using activity based costing methods. Dynamic programming is then used to obtain an optimal set of product development processes with the objective of optimizing the overall product development cost. This system is built using object oriented modeling methods.

Integrating Advanced Computer-Aided Design, Manufacturing, and Numerical Control: Principles and Implementations

For many years, computers have been playing a prominent role in the process of product design and manufacture. As manufacturing continues to march into the future, there is a critical need to address the role of computer technologies in an integrated fashion, placing emphasis on product data exchange as well as product data management. Integrating Advanced Computer-Aided Design, Manufacturing, and Numerical Control: Principles and Implementations presents basic principles of geometric modelling while featuring contemporary industrial case studies. A one-stop reference source for the latest field standards, this comprehensive title expands beyond the traditional scope of the product development process to give a brief account on product data management (PDM) and product lifecycle management (PLM).

Relationship matrix based automatic assembly sequence generation from a CAD model

Currently in industry, design and communication of a product assembly is through the use of computer-aided design (CAD) systems. However, there are no commercial systems that can automatically generate feasible assembly sequence plans. There is past and current academic research in methods to provide automatic assembly sequence planning. Assembly sequence planning using a commercial system often relies on an expert assembly sequence planner, and it is predominantly done manually. This requires a great amount of time and expert knowledge; assembly sequence plans generated may not even be the most efficient. The ability to automatically generate assembly sequence plans will lead to the reduction of planning time, less reliance on the amount of knowledge required, and better plans at earlier stages of the design process. CAD models are based on feature constraints to create and define an assembly. The challenges to automatically generate assembly sequences using CAD models lie in intelligent reasoning and analysis of the modelled assembly data. Based on past research findings, there is a reason to believe that assembly constraints used in CAD assembly models can provide essential information related to the assembly process. This paper presents a system that can analyse and utilize assembly data available from a CAD model to generate assembly sequences. The system also considers a user input as a type of assembly constraint. The system is capable of producing a set of ranked feasible assembly sequence plans for an operator to evaluate. A matrix approach has been adopted to process the information retained from a CAD model. Interference and stability studies are carried out during the creation of assembly sequence plans. The outputs are ranked based on the ease of assembly and the stability of the generated assembly sequence plans. Case studies are used to evaluate the system and the feasibility of the output. A case study using a two stroke engine is presented, which demonstrates how the system generates assembly sequence plans.