A framework for collaborative top-down assembly design

This paper presents a new system framework for collaborative top-down assembly design. Different from current computer-aided design (CAD) systems, the framework allows a group of designers to collaboratively conduct product design in a top-down manner. In our framework, a multi-level and distributed assembly model is adopted to effectively support collaborative top-down assembly design. Meanwhile, fine-granularity collaborative design functionalities are provided. First, the coupled structural parameters involved in the distributed skeleton models of the product can be collaboratively determined by the correlative designers based on fuzzy and utility theory. Second, agent based design variation propagation is achieved to ensure the consistency of the multi-level and distributed assembly model during the whole design process. Third, collaborative design of assembly interfaces between the components assigned to different designers is supported. The prototype implementation shows that our framework works well for supporting practical collaborative top-down assembly design.     

Integrate design structure matrix with carbon footprint for product low carbon design

Product low-carbon design plays a significant part in reducing carbon footprint during the product life cycle. This paper proposed Design Structure Matrix integrated with Carbon Footprint (DSM-CF) to design for low carbon footprint. After the carbon footprint for product life cycle is discussed in detail, the DSM-CF is also proposed. The construction, decomposition and clustering algorithm of DSM-CF model is then put forward in detail. The impact of the carbon footprint of each design task on the entire product life cycle is analyzed, which could effectively reduce the carbon footprint of products. At the end of this paper, the DSM-CF model of the hand rehabilitation robot system is established to verify the effectiveness of the model.     

Integrated product and process design: a multi-objective modeling framework

In this paper we present an analytical multi-objective framework for the concurrent design of product and processes. The objective is to simultaneously consider the tolerance specification on the product or the component dimensions along with the selection of the manufacturing processes. For this purpose we consider three objectives: to minimize unit cost, to minimize quality loss and to minimize manufacturing lead time. We characterize the properties of the non-dominated solutions. These solutions provide flexibility needed in an agile manufacturing environment. The min–max approach is used to obtain trade-off solutions.     

Defining decision making process performance: Conceptualization and validation of an index

Many studies have demonstrated the impact of information technology (IT) on decision making but few have used decision making process performance (DMPP) as a dependent variable. Our study proposes a rich formative conceptualization of DMPP, a valid and reliable measure for this construct, and studies its influence on the quality of decision making. The results show that DMPP is a formative second-order aggregate construct composed of procedural rationality, exhaustivity of the information analyzed, openness of spirit, and effort. This study illustrates the importance of building proper definitions of constructs and contributes to the development of shared meaning in IS.     

An integration framework for product lifecycle management

The need for integrating business and technical information systems, allowing partners to collaborate effectively in creating innovative products, has motivated the design and deployment of a novel integration framework for product lifecycle management. The time is ripe for such an integration framework because of the convergence of three important developments, almost in a perfect storm: (1) maturity of standardized product data and meta-data models, and standardized engineering and business processes; (2) emergence of service-oriented architecture for information sharing; and (3) availability of robust middleware to implement them. These developments allow engineering and business objects and processes to be built or composed as modular pieces of software in the form of services that can communicate with each other and be used across different parts of a business. These modular software pieces can be reused and reconfigured in new ways as business conditions change, thereby saving time and money for companies. This paper describes the business and technical aspects of an integration framework for product lifecycle management using open standards and service-oriented architecture.     

On bilevel multi-follower decision making: General framework and solutions

Within the framework of any bilevel decision problem, a leader’s decision is influenced by the reaction of his or her follower. When multiple followers who may have had a share in decision variables, objectives and constraints are involved in a bilevel decision problem, the leader’s decision will be affected, not only by the reactions of these followers, but also by the relationships among these followers. This paper firstly identifies nine different kinds of relationships (S₁ to S₉) amongst followers by establishing a general framework for bilevel multi-follower decision problems. For each of the nine a corresponding bilevel multi-follower decision model is then developed. Also, this paper particularly proposes related theories focusing on an uncooperative decision problem (i.e., S₁ model), as this model is the most basic one for bilevel multi-follower decision problems over the nine kinds of relationships. Moreover, this paper extends the Kuhn-Tucker approach for driving an optimal solution from the uncooperative decision model. Finally, a real case study of a road network problem illustrates the application of the uncooperative bilevel decision model and the proposed extended Kuhn-Tucker approach.     

Knowledge representation framework for interactive capture and management of reflection process in product concepts development

A design process can be characterized by reflection-in-action; that is, the process consists of a series of problem solving activities and each is embodied with a problem and a solution. In this process, a designer represents a hypothetical concept on each design alternative, deploys and verifies the concept from multiple viewpoints considering other alternatives, and modifies it. An advanced integrated design environment should be based on a representation framework that embodies this process of reflection in concept development, which usually remains in the realm of the designer’s tacit knowledge. This paper proposes a knowledge representation framework for an integrated design environment, named DRIFT (Design Representation Integration Framework of Three layers), which interactively captures and manages reflection processes of generating and verifying design concepts. The core of DRIFT is a three-layered design process model of actions, operations, and argumentation. This model integrates various design tools and captures performed design activities. The action level captures the sequence of design operations. The model operation level captures the transition of design states, recording a design snapshot over design tools, which are integrated through ontology-based representation of design concepts. The argumentation level captures the process of defining problems and corresponding alternative solutions. Integration of three levels with a template of design operation extracted from Design-For-X approaches enables a proposed system to interactively and efficiently capture and manage the process of design concept development through operations over design tools. A design operation template works to limit the number of links between the three levels remaining easy to manage its semantics. This paper also demonstrates a prototype implementation of DRIFT and its application to conceptual design of a small mechatronic system with a system modeling method. The paper concludes with a discussion of some future issues.     

An adaptive design process generated by the integration of systematic design process and design patent protection mechanism

The conventional design processes are merely directed at measures for resolving problems, but fail to feature measures for procuring design patent protection. To overcome such a shortage, the authors have made a breakthrough by integrating the systematic design process (SDP) and design patent protection mechanism (DPPM) to develop an adaptive design process (ADP). The ADP includes 14 steps, as follows: (1) Problem, (2) Analysis, (3) Patent needs, (4) Concept, (5) Patent database searching, (6) Design database searching, (7) Integration, (8) Evaluation, (9) Decision, (10) Claim, (11) Solution, (12) Monitor, (13) Enforce and (14) Patent protection. In actual implementation, ADP allows designers to create novel creations easily and helps efficient procurement of design patent protection. In summary, ADP is a brand new design process with an advanced and effective nature.     

A systematic decision making approach for product conceptual design based on fuzzy morphological matrix

Conceptual design plays an important role in development of new products and redesign of existing products. Morphological matrix is a popular tool for conceptual design. Although the morphological-matrix based conceptual design approaches are effective for generation of conceptual schemes, quantitative evaluation to each of the function solution principle is seldom considered, thus leading to the difficulty to identify the optimal conceptual design by combining these function solution principles. In addition, the uncertainties due to the subjective evaluations from engineers and customers in early design stage are not considered in these morphological-matrix based conceptual design approaches. To solve these problems, a systematic decision making approach is developed in this research for product conceptual design based on fuzzy morphological matrix to quantitatively evaluate function solution principles using knowledge and preferences of engineers and customers with subjective uncertainties. In this research, the morphological matrix is quantified by associating the properties of function solution principles with the information of customer preferences and product failures. Customer preferences for different function solution principles are obtained from multiple customers using fuzzy pairwise comparison (FPC). The fuzzy customer preference degree of each solution principle is then calculated by fuzzy logarithmic least square method (FLLSM). In addition, the product failure data are used to improve product reliability through fuzzy failure mode effects analysis (FMEA). Unlike the traditional FMEA, the causality relationships among failure modes of solution principles are analyzed to use failure information more effectively through constructing a directed failure causality relationship diagram (DFCRD). A fuzzy multi-objective optimization model is also developed to solve the conceptual design problem. The effectiveness of this new approach is demonstrated using a real-world application for conceptual design of a horizontal directional drilling machine (HDDM).     

基于风险和稳健决策的产品设计链伙伴选择

在产品研发过程中存在不确定性因素,导致产品研发存在一定的风险.在时间和成本约束下,提出了基于风险和稳健决策的设计链伙伴选择模型.对产品研发过程中存在的风险进行量化和集总,在不同的决策态度下实现了产品研发对时间、成本和风险的控制要求.最后通过算例对模型进行了仿真.     

Development of fuzzy process accuracy index for decision making problems

Several statistical decision making tools and methods are available to organize evidence, evaluate risks, and aid in decision making. Process capability indices are the summary statistics to point out the process performance. In this paper, these indices are analyzed to obtain a new decision making tool. Process accuracy index (C_a) measures the degree of process centering and gives alerts when the process mean departures from the target value. It focuses on the location of process mean and the distance between mean and target value. We modify the traditional process accuracy index to obtain a new tool under fuzziness. With the proposed tool, specification limits and process mean can be defined as triangular or trapezoidal fuzzy numbers. The proposed tool is illustrated to solve a supplier selection problem.     

A framework for dynamic multiple-criteria decision making

The classic multiple-criteria decision making (MCDM) model assumes that, when taking a decision, the decision maker has defined a fixed set of criteria and is presented with a clear picture of all available alternatives. The task then reduces to computing the score of each alternative, thus producing a ranking, and choosing the one that maximizes this value.However, most real-world decisions take place in a dynamic environment, where the final decision is only taken at the end of some exploratory process. Exploration of the problem is often beneficial, in that it may unveil previously unconsidered alternatives or criteria, as well as render some of them unnecessary.In this paper we introduce a flexible framework for dynamic MCDM, based on the classic model, that can be applied to any dynamic decision process and which is illustrated by means of a small helicopter landing example. In addition, we outline a number of possible applications in very diverse fields, to highlight its versatility.     

Trust-based consensus reaching process for product design decision-making with heterogeneous information

Pursuing a consensual result is vital for selecting optimum product design schemes as it helps eliminate preference conflicts in product design decision-making (PDDM). As a dynamic and iterative activity, the consensus reaching process (CRP) of PDDM always involves heterogeneous, vague, and inconsistent information, which makes it challenging to adjust decision-makers’ judgement to achieve an acceptable consensus level. To address this issue, triangular fuzzy numbers were introduced to depict decision-makers’ heterogeneous judgement. The indicator weights were determined by integrating the fixed weight obtained from the interval analytic hierarchy process (IAHP) and the variable weight acquired using the maximizing deviation method. Decision-makers’ weights were identified through a combination of the uncertainty degree measured by fuzzy entropy and the consistency degree solved by a distance minimizing model of the PDDM matrix. A dynamic CRP for PDDM was proposed by adjusting decision-makers’ judgement based on their trust relationships and updating the PDDM matrix in an evolutionary manner. A case study is conducted to verify the feasibility and effectiveness of the proposed method.     

基于决策过程的个性化推荐系统设计

电子商务的深度发展要求信息技术必须与商务原理结合。现有的个性化推荐系统大多强调推荐内容的精准性,而忽视了推荐结果的利润性和推荐列表的多样性。从消费者与企业的决策过程出发,将消费者购物决策过程简化为意识与满意,将企业决策分为推荐回应与利润计算,以企业推荐商品的利润最大化为目标,设计了一个三层结构的个性化推荐系统,给出了数据支持层、类别分类层和推荐结果层的逻辑算法。针对该系统的实验结果表明,在推荐精准度、多样性和利润度上,都达到较优效果。     

Development and application of a framework for comparing early design methods for young children

When designing with young children, designers usually select user centred design methods based on the children’s required level of engagement and the inspiration expected to be created according to the designer. User centred design methods should be selected for their suitability for children and for the quality of the output of the design method. To understand the suitability of design methods, a framework was developed to describe design methods in terms of required design skills as identified by the Theory of Multiple Intelligences. The proposed framework could provide the basis for a tool to compare design methods and to generate hypotheses about what design method would work optimally with children in a specific school grade. The initial examination of the viability of the framework is a comparison of design methods by the number of skills involved; earlier work showed that the involvement of more skills (as with, e.g. low-fi prototyping) could result in more options for a design problem than the involvement of fewer skills (as with e.g. brainstorming). Options and Criteria were counted to understand the quality of the method in terms of the amount of design-information. The results of the current paper indicate that 8-to-10-year-old children generate significantly more options in prototyping sessions than when they are involved in sessions applying a Nominal Group Technique. The paper indicates that (a) with the framework we can generate hypotheses to compare design methods with children and (b) that the outcome of various design methods, which might lead to very different representations, can be compared in terms of Options and Criteria. Further usage of the framework is expected to result in empirical support for selecting a design method to be applied with young children.     

Knowledge integration and sharing for collaborative molding product design and process development

This study presents a systematic approach to developing a knowledge integration and sharing mechanism for collaborative molding product design and process development. The proposed approach includes the steps of (i) collaborative molding product design and process development process modeling, (ii) an ontology-based knowledge model establishment, (iii) knowledge integration and sharing system framework design, (iv) ontology-based knowledge integration and sharing methods development, and (v) ontology-based knowledge integration and sharing mechanism implementation. The mechanism can support collaborative molding product design and process development by providing functions of knowledge integration and sharing. Results of this study facilitate the knowledge integration and sharing of collaborative molding product design and process development to satisfy the product knowledge demands of participants, and thus increase molding product development capability, reduce molding product development cycle time and cost, and ultimately increase molding product marketability.     

Knowledge-based integrated product design framework towards sustainable low-carbon manufacturing

With a global challenge on the serious ecological problems, low-carbon manufacturing aiming to reduce carbon emission and resource consumption is gaining the ever-increasing attention. Due to the significant impact on the product lifecycle, low-carbon product design is considered as an effective and attractive approach to improve the eco-market trade-off of electromechanical products. Existing low-carbon product design approaches focus on solving specific low-carbon problems, and how to explore and navigate the integrative design space considering low-carbon and knowledge in a holistic perspective is rarely discussed. In response, this paper proposes a knowledge-based integrated product design framework to support low-carbon product development. An ontology-based knowledge modelling approach is put forward to represent the multidisciplinary design knowledge to facilitate knowledge sharing and integration. Subsequently, a function–structure synthesis approach based on case-based reasoning is presented to narrow down the design space to generate suitable design solutions for achieving desired functions. A multi-objective mathematical model is established, and the multi-objective particle swarm optimization is adopted to solve the low-carbon product optimization. Furthermore, a decision-making ranking approach based on the closeness degree is employed to prioritize the potential solutions from Pareto set. Finally, a case study of low-carbon product design of hydraulic machine is demonstrated to show the effectiveness.     

A taxonomy and decision support for the design and manufacture of types of product families

The realization that designing products in families can and does have significant technological and economic advantages over traditional single product design has motivated increasing interest in recent years in formal design tools and methodologies for product family design. However, currently there is no guidance for designers in the first key strategic decisions of product family design, in particular determining the type of product family to design. Hence, in this paper, first a taxonomy of different types of product families is presented which consists of seven types of product families, categorized based on number of products and time of product introduction. Next a methodology is introduced to support designers in deciding which type of product family is appropriate, based upon early knowledge about the nature of the intended product(s) and their intended market(s). From this information it follows both which manufacturing paradigm and which fundamental design strategies are appropriate for each type of product family. Finally, the proposed methodology is illustrated through a case study examining a family of whitewater kayaks.     

Computer-aided design-while-engineering technology in top-down modeling of mechanical product

In order to considerably reduce the overall time and cost associated with design process, it has been widely noted that data consistence and a unified software platform play a vital role in CAD/E integrated design. A novel modeling mechanism named as CADWE (Computer-Aided Design-While-Engineering) is proposed to merge CAD and CAE application into a unified pattern. Meanwhile,the CADWE maintains top–down modeling process and change propagation in complex product design. Preliminary model is adopted to build up consistent and shareable integration information model instead of focusing on programming to link different model to keep the consistence. Particularly, generalized feature and agent of preliminary geometry are put to use to achieve synchronous and automatic change propagation from preliminary geometry to detailed model and FEM application. Thus, not only numerous duplication and human error in complex simplification operation and incompatible data exchange may be avoided, but also much software development is dispensable. A software package is developed and used in change propagation with the aid of NX/Open API. To explain the CADWE modeling process with more insight, two examples are used as the case studies. By means of the comparison with the techniques in the literatures high relevant to this topic, it proves that the CADWE technology is good at handling complicated product modeling and their change propagation with little software development.     

An assembly oriented design framework for product structure engineering and assembly sequence planning

The paper describes a novel framework for an assembly-oriented design (AOD) approach as a new functional product lifecycle management (PLM) strategy, by considering product design and assembly sequence planning phases concurrently. Integration issues of product life cycle into the product development process have received much attention over the last two decades, especially at the detailed design stage. The main objective of the research is to define assembly sequence into preliminary design stages by introducing and applying assembly process knowledge in order to provide an assembly context knowledge to support life-oriented product development process, particularly for product structuring. The proposed framework highlights a novel algorithm based on a mathematical model integrating boundary conditions related to DFA rules, engineering decisions for assembly sequence and the product structure definition. This framework has been implemented in a new system called PEGASUS considered as an AOD module for a PLM system. A case study of applying the framework to a catalytic-converter and diesel particulate filter sub-system, belonging to an exhaust system from an industrial automotive supplier, is introduced to illustrate the efficiency of the proposed AOD methodology.