Towards a generic product modelling framework

In response to the current rapidly changing manufacturing environment, product modelling technology has been widely applied to provide the essential information for product development (PD) processes. The traditional product modelling technologies are unable to support the information exchange and share in various stages of PD processes that could be taken place among departments in a company or even among companies in distributed manufacturing environment. This has caused many problems such as information loss, data format incompatibility and reduced efficiency and effectiveness of product data applications. This has consequently created bottlenecks for the integration of PD processes. In this paper, a generic product modelling framework (GPMF) is proposed to overcome the abovementioned problems in today's manufacturing environment. This framework uses the standard for the exchange product model data (STEP) as a foundation. It consists of four functional components: an EXPRESS data model namely EDM; a STEP–based modelling environment; a “five-phase” modelling method; and three EDM data exchange and sharing methods. Case studies show that the product models built based on the GPMF are capable of integrating information in product design, manufacturing and assembly. The GPMF is compatible, comprehensive, and flexible, and is able to support information exchange and sharing.     

Information supported design for manufacture of injection-moulded rotational products

Whilst the concurrent engineering philosophy has been embraced by a wide range of engineering companies as a means to remaining competitive, the design software tools which are commercially available are limited in their ability to offer concurrent support. This paper describes research which has investigated how design for manufacture information can be provided back to designers as concurrently as possible. The paper, using injection moulding as its focus, illustrates how a design for manufacture environment can be structured to utilize company product and manufacturing information. In particular, the need for appropriate information translation mechanisms and design support strategies is described. An example, highlighting the potential of the approach and utilizing an experimental object-oriented system, is discussed.     

UL-PML: constraint-enabled distributed product data model

The global economy has made manufacturing industry more distributed than ever before. Product design requires more involvement from various technical disciplines at different locations. In such a geographically and temporally distributed environment, efficient and effective collaboration on design is vital to maintain product quality and organizational competency. Current standard computer-aided design data formats do not support design collaboration effectively in terms of design information and knowledge capturing, exchange, and integration. Design constraints cannot be represented and transferred among different groups, and design information cannot be integrated efficiently within a distributed environment. A new design data model, the Universal Linkage model, is developed here to represent design-related information for network-based collaborative design. It incorporates geometric and non-geometric constraints with traditional geometric elements, thus allowing more design knowledge sharing in collaborative design. Segments of design information can be linked and integrated into a set of complete product data. Thus, lean information exchange can be realized. This model, which has good properties of openness and extensibility, is represented by Directed Hyper Graph and Product Markup Language.     

Recent development on product modelling: a review

Product modelling is a pivotal activity in product development (PD) processes. Well-defined product models organize product data, production information and knowledge to satisfy the requirements of the rapid changes of the PD environment. In this paper, a comprehensive review is carried out on the recent development of product modelling technology. Four types of product modelling methodologies are discussed in detail. Two object-oriented product modelling methods: STEP-based product modelling and UML-based product modelling are reviewed and compared. The research gaps and issues are identified. To implement the product modelling into current integrated manufacturing environment, a generic product modelling framework is proposed. The future research trend of product modelling is also discussed.     

Enhancing product development through a dynamic information interchange approach

In today's increasingly competitive environment, firms are experiencing growing pressure to reduce the product development lead time to meet market expectations. In this paper, a Responsive Product Development System (RPDS), which is used to model the product development process and the components of the process with object technology, introduces a dynamic product information schema characterized by its ability to provide design practitioners with a product data exchange standard, thus transforming data to information and then knowledge. To validate the feasibility of the proposed schema, a case study has been conducted in a plastic product factory based on the suggested approach. Following feedback from these companies, a further review of the design of the proposed system has been conducted to ensure efficient information flow across the heterogeneous computing environment. A measure of loss to society associated with RPDS in product development time is also included as a system evaluation.     

Lean practices implementation and their relationships with operational responsiveness and company performance: an Italian study

Although many firms report large benefits from lean implementation, a lot of scepticism still remains regarding attainable results and the possibility to apply Lean approach outside high-volume manufacturing and stable context. In this work, combining field interviews with literature review, theoretical connections have been developed among Lean manufacturing techniques, operational responsiveness and company growth performances. A conceptual model has been proposed for investigating the network of influences among lean practices (supplier management, human resource management, just-in-time and total quality management practices), operational responsiveness (Product mix variety, Product innovation and Time effectiveness) and company growth performances in Italian companies. Using structural equation modelling, a second-order confirmatory factor analysis has been used to test the hypothesised relationships in the structural models. This study highlights that the operational responsiveness is only partially connected to a Lean strategy of a company. Indeed, the lean practices implementations are negatively influenced by product mix variety and innovation, while positively influenced by time effectiveness variables. Moreover, product mix variety and time effectiveness are the main characteristics of the operational responsiveness that positively influences company growth performances. So time effectiveness could be considered as a mediator between Lean best practices and firm growth. Moreover, no direct relationship has been found between lean bundles and firm’s performances. Lack of resources and mainly poor communication and managers’ commitment and support seem to be the main obstacles of lean implementation and success.     

Ceramic microfabrication by rapid prototyping process chains

Fabrication of micropatterned ceramics or ceramic microparts make high demands on the precision and resolution of the moulding process. As finishing of miniaturised or micropatterned ceramic components is nearly impossible, shaping has to be done by a replication step in the green, unfired state. To avoid high tooling costs in product development, a rapid prototyping process chain has been established that enables rapid manufacturing of ceramic microcomponents from functional models to small lot series within a short time. This process chain combines the fast and inexpensive supply of master models by rapid prototyping with accurate and flexible ceramic manufacturing by low-pressure injection moulding. Besides proper feedstock preparation and sufficient small grain size, the quality of the final components is mainly influenced by the quality of the master model. Hence, the rapid prototyping method must be carefully selected to meet the requirements of the component to be fabricated.     

Distributed knowledge sharing for collaborative product development

Product development is a knowledge-intensive activity in manufacturing enterprises. This paper analyses various forms of knowledge resources in the product development process and studies the representation scheme for them. Then a novel distributed knowledge sharing model is proposed for spreading and sharing knowledge among engineers in collaborative product development teams. In a collaborative team, engineers usually come from diverse disciplines; their demands for knowledge are also different from each other. The proposed knowledge sharing model could deliver the proper knowledge to the engineers who may need them. Moreover, our model is based on the engineers’ personal knowledge repositories rather than the centralised team knowledge repository in the collaborative team. The proposed model could bring out an efficient and proactive way for knowledge sharing among engineers in the product development process. The efficiency and usability of the proposed model are validated by experiments referring to the knowledge sharing in a real-world collaborative team of a manufacturing enterprise.     

A model for co-evolution in manufacturing based on biological analogy

Manufacturing systems continue to adapt in order to survive the changing and challenging markets and global competition. Product and manufacturing design and capabilities are configured to allow the needed adaptation through innovative design, improved system paradigms, intelligent design and optimisation models, and product grouping to increase efficiency. In this research, it is hypothesised that the evolution and co-evolution of products and the machines used to manufacture them is akin to that observed in the adaptation of biological species. The symbiosis between products and manufacturing capabilities is studied using real examples, and a new model that establishes the symbiotic relationship between their evolution paths and observed co-evolution trends based on available historical information is proposed. Dual cladograms are used to track their evolution and detect useful potential development and plausible future evolution trends. When a state of co-evolution equilibrium is reached, a stimulus for more abrupt changes would be needed to cause further evolution on both sides. The co-evolution model has been applied to an example based on analysing the history of machine tools development and data from a major machine tools manufacturer. The evolution and co-evolution hypotheses of machined parts and machine tools were charted up to the currently observed state of equilibrium in this application field. This innovative model of co-evolution in manufacturing can help improve the utility of manufacturing resources and prolong the life of manufacturing systems beyond a single product generation and its variants.     

A unified product structure management for enterprise business process integration throughout the product lifecycle

Information availability is a key factor for business success and competitive advantage. While created by design engineers, product structure is accessed and referenced by other users involved in product lifecycle from various departments. However, there is a lack of efficient ways of managing product structure information for enterprise business process integration. This study proposes a unified product structure management model to fill in this gap. With this proposed model, the product structure is managed in a unified way and can be accessed by different people with various disciplines in the right formats throughout the entire product lifecycle, including business processes of quotation, sales order processing, design, planning, scheduling, production, and delivery. This research is part of the enterprise business information management system project whose purpose is to streamline the information management for key business processes to integrate multi-disciplines in an enterprise for product development. A prototype system has been implemented to verify the model developed by taking real cases in a mould-manufacturing company. The results show the potential for substantial improvements in industrial competitive advantage.     

Improving the implementation effectiveness of cellular manufacturing: a comprehensive framework for practitioners

In today's competitive environment cellular manufacturing (CM) is a well-known strategy in improving manufacturing performance. To obtain the full benefits that CM has to offer successful implementation is a critical factor. Evidence indicates that firms converting to CM often struggle with implementation and achieve results that are less than anticipated. A comprehensive review of implementation literature was undertaken and a multi-phase model developed and evaluated through a case study. The framework recognizes the importance of both technical and human aspects of CM and provides practitioners with a better understanding of the various phases in the implementation process, including the many activities and issues which need to be considered for each step. In the case study company, implementation of CM not only provided many of the benefits associated with this form of manufacturing but also allowed operators to become a value-adding link in respect to process and product improvement and new product development.     

集成产品模型

产品模型作为对产品生命周期中产品信息描述的一种手段，已经成为实现制造自动化的关键技术。本文介绍产品模型的概念及其发展过程，从零件信息描述裙带性和设计过程的逻辑完整性发出，提出了一种基于关系型ＣＡＤ和产品数据管理（ＰＤＭ）系统的集成产品模型，并讨论了该产品模型的特点及基本原理。     

应用于快速响应设计的产品动态模型

通过分析产品模型的研究现状,论述建立适应产品快速响应设计需求的产品模型的必要性,并指出相应的产品模型应具有的特性。在此基础之上,引入产品动态模型定义,分析其子模型、子模型的多视图定义及表示方法。     

Coordinated optimisation of platform-driven product line planning by bilevel programming

Product line planning (PLP) aims at an optimal combination of product feature offerings, suggesting itself to be a determinant decision for a company to satisfy diverse customer needs and gain competitive advantages. Fulfilment of planned product lines must make trade-offs between product variety and production costs. To balance the costs of product lines, manufacturers often adopt a product platform configuration (PPC) approach to redesign product and process platforms by adding new modules to the legacy platforms. The PPC is an effective means of providing product variety while controlling the manufacturing costs. The PLP and PPC problems have traditionally been investigated separately in the marketing research and engineering design fields. It is important to coordinate PLP and PPC decisions within a coherent optimisation framework. This paper proposes a bilevel mixed 0–1 nonlinear programming model to formulate coordinated optimisation for platform-driven product line planning. The upper level deals with the PLP problem by maximising the profit of an entire product line, whilst the lower level copes with the multiple product platforms optimisation for the optimal PPC in accordance with the upper level decisions of product line structure. To solve this bilevel programming model, a bilevel genetic algorithm is developed to find the optimal solution. A case study of coordinated optimisation between an automobile line and its product platforms is presented to demonstrate the feasibility and effectiveness of the proposed bilevel programming in comparison with a typical ‘all-in-one’ approach and a non-joint optimisation programming.     

Information mapping across injection moulding design and manufacture domains

The process of developing new products is complex, partly due to the wide areas of expertise that need to work together to achieve the best results. Whilst a broad range of software tools is now available to support specific areas of product development, and Product Lifecycle Management systems are starting to support information sharing, the provision of software environments that enable the sharing of information and knowledge across multiple domains of expertise is still a major issue. This paper utilises a set of engineering domain ontologies and investigates the development of mapping methods between them. The work focuses on the development of plastic injection moulded products and has used the particular domains of mouldability, mould cavity design and mould cavity manufacturing to explore the mapping methods across domains. It identifies the critical requirement for mapping methods as understanding the pre-conditional knowledge that constrains the domain boundaries. Experimental mapping methods based on these requirements have been constructed and are discussed in the context of case studies in information sharing for injection moulded product development.     

Learning curve modelling of work assignment in mass customized assembly lines

In customized markets, a large variety of product models is demanded by customers. That requires fast set-up of production resources to comply with specifications of the next model to be produced. Such compliance, however, may cause considerable production and quality losses owing to workers’ poor performance during the initial production runs of a new model. Therefore, modelling workers’ learning upon exposure to each product model may help production managers to define the best assignment scheme for models and workers, such that losses in the initial stages of production are minimized. The current paper presents a method that uses learning curves to guide the best assignment of product models to teams of workers. Product models are first clustered into families based on their similarities, aiming at a smaller data collection to generate the learning curves. Allocation of product families to teams is then carried out, based on the analysis of their corresponding learning curves. Two courses of action are proposed for this, depending on whether the production batch will lead to longer or shorter production runs. The proposed methodology is illustrated in a case study from the shoe manufacturing industry.     

Alternative production strategies based on the comparison of additive and traditional manufacturing technologies

Additive manufacturing technology has been evolving for several years. New material options, better processing speeds and greater autonomy are some of the characteristics of this technology that are still under research. However, in its current state, many commercially available 3D printers are competing with traditional manufacturing techniques in the fabrication of end-use products. In this paper, different additive manufacturing technologies are compared with injection moulding in a real-world case study. The comparison is conducted in terms of lead time and total production cost. From the case under study, it becomes obvious that none of the additive manufacturing technologies examined is yet able to practically replace injection moulding for medium- and high production volumes. However, when considering low-volume production, both rapid tooling and additive manufacturing may offer an alternative that could result into shorter lead times and decreased total production costs. In addition, the introduction of Additive Manufacturing in a producer’s production portfolio can increase flexibility, reduce warehousing costs and assist the company towards the adoption of a mass customisation business strategy.     

Modelling, analysis, and acceleration of a printed circuit board fabrication process

Product design and fabrication constitute an important business activity in any manufacturing firm. Designing an optimized product fabrication process is an important problem in itself and is of significant practical and research interest. In this paper, we look into a printed circuit board (PCB) fabrication process and investigate ways in which the fabrication cycle time can be minimized. Single class queueing networks constitute the modelling framework for our study. The model developed in this paper and the analysis experiments carried out are based on extensive data collected on a PCB fabrication company located in Bangalore, India. This is a representative PCB fabrication company involving multiple, concurrent fabrication works with contention for human/technical resources. Our model seeks to capture faithfully the flow of the fabrication process in this company and such other organisations, using queueing networks. Using the model developed, we explore how the cycle times can be reduced using input control, load balancing, and variability reduction. The model presented is sufficiently generic and conceptual; its scope extends beyond that of a PCB fabrication organization.     

Event-driven multi-agent ubiquitous manufacturing execution platform for shop floor work-in-progress management

It has been reported that radio frequency identification (RFID) technology is applied to manufacturing shop floors for capturing and collecting real-time field data. Real-time information visibility and traceability allows decision makers to make better-informed shop floor decisions. It has been a great challenge to process a huge amount of RFID data into useful information for managerial uses. This paper presents an event-driven shop floor work-in-progress (WIP) management platform for creating a ubiquitous manufacturing (UM) environment. The platform aims to monitor and control dynamic production and material handling through RFID-enabled traceability and visibility of shop floor manufacturing processes. The platform provides facilities to process shop floor real-time RFID events and to aggregate actionable and meaningful operational information to support decision-making activities. An information processing mechanism based on a critical event model is proposed to organise real-time field data in various abstract levels for enterprise decisions. A case study at an air conditioner manufacturing company is used to demonstrate how the proposed platform can benefit its shop floor WIP management by showing how production and logistic operators and their supervisors accomplish their tasks.     

美国汽车业的供应链策略分析——互联网的影响

互联网的建立 ,实现了大量的信息流动 ,因而使供应链的本质起了极大的变化。汽车制造商为取得竞争优势 ,需要对其战略重新定位。为了得到更大的市场 ,公司必须做到以下两点 :一是缩短产品生产周期 ;二是缩短产品开发周期。为了降低成本 ,公司必须降低整条价值链中每一个环节的成本。商家通过互联网向顾客销售汽车及零部件 ,使得商家在配送和零售的模式上发生了很大的变化。这一变化不仅向公司提供了更好的市场透明度 ,更向消费者提供了直接挑选货品的机会。商家为顾客开启的大门还削减了传统销售中用于配送和零售的中介费用。本文的目的在于研究互联网中企业对企业的影响 ,以及今后应该如何置身于这一业务。供应商和汽车制造商应如何在互联网时代进行商业行为呢 ?本文的目的在于分析传统的 ,即以竞争和合作为特征的供应链关系的变化。我们将着眼于供应关系的改变、成本模式和样式转变等。本文结构如下 :第一节是对目前问题及其重要性的介绍 ;第二节主要讨论问题的一般表示形式 ,以及为取得战略竞争优势 ,解决问题的方法。第三节详细分析了汽车业的各个方面及其供应链。最后提出了企业的战略和结论。