Early Phases Of Product Design Research Articles

Development of a design space for dissimilar materials joining in aerospace applications

Abstract This research paper presents an application of the integrated process and product design (IPPD) approach for selecting the best joint configuration for dissimilar material joining in the early product design phase. The proposed methodology integrates the multi-criteria decision making (MCDM) approach with quality function deployment (QFD) to identify the key criteria for joint selection, including load-carrying capacity, size, cost per joint, ease of manufacturing, time consumption and deformation. Three types of joints (rivet, weld and adhesive) and two hybrid joints (adhesive-weld and adhesive-rivet) are considered for three dissimilar material configurations: carbon fiber-reinforced plastic (CFRP) aluminum, CFRP steel, and aluminum-steel. QFD is utilised to transform job requirements into design criteria, and in the second phase, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is employed to choose the optimal joint configuration based on the weighted criteria acquired in the previous phase. The selected joint configuration is then validated through experimental study. The findings demonstrate that the proposed IPPD approach with QFD-TOPSIS techniques is highly effective for selecting mechanical joints for dissimilar material joining in the early design phase. The study concludes that the adhesive-rivet hybrid joint is the optimal solution among all alternatives. The proposed methodology can ultimately lead to improved product reliability and performance, as well as reduced development time and cost.

Contribution of the quality costs to sustainable development

Abstract This paper presents a framework of contemporary quality costs concept contributing to a more sustainable society regarding an integrated view of quality costs in all phases of the product life cycle (engineering, production, use, and end-of-life) by all stakeholders in the supply chain. The development of this framework is viewed through the complementarity of the sustainability dimensions and the circular economy concept understood as a waste management concept, which represents a solid basis for the development of a novel approach to understanding quality costs which, in turn, reflects the sustainable quality concept. By providing sustainable criteria (economic, environmental, and social) as an integral part of the quality costs concept, this framework will improve the sustainability performance in the early phases of product design, increase the added value of the products and the duration of the added value, and strengthen the responsibility of all stakeholders beyond the limits of their organizational processes. This will inevitably lead to changes to the quality cost structure, dominated by new quality costs elements which reflect sustainability. This research demonstrates the findings that should support the setting the theoretic assumptions for the development of a sustainable quality cost generic model.

Development of Technical Creativity Featuring Modified TRIZ-AM Inventive Principle to Support Additive Manufacturing

Abstract The design for additive manufacturing (DFAM) processing was introduced to fully utilize the design freedom provided by additive manufacturing (AM). Consequently, appropriate design methodologies have become essential for this technology. Recently, many studies have identified the importance of DFAM method utilization to produce AM parts, and theory of inventive problem-solving (TRIZ) is a strategy used to formalize design methodologies. TRIZ is a problem-solving tool developed to assist designers to find innovative and creative solutions. However, the pathway for synergizing TRIZ and DFAM is not clearly explained with respect to AM capabilities and complexities. This is mainly because most methods continue to involve use of the classical TRIZ principle, which was developed early in 1946, 40 years before AM technologies were introduced in the mid-1980s. Therefore, to tackle this issue, this study aims to enhance the 40 principles of classical TRIZ to accommodate AM design principles. A modified TRIZ-AM principle has been developed to define the pathway to AM solutions. TRIZ-AM cards are tools that assist designers to select inventive principles in the early phases of product design and development. The case study illustrates that even inexperienced AM users can creatively design innovative AM parts.

Classifying Component Function in Product Assemblies With Graph Neural Networks

Abstract Function is defined as the ensemble of tasks that enable the product to complete the designed purpose. Functional tools, such as functional modeling, offer decision guidance in the early phase of product design, where explicit design decisions are yet to be made. Function-based design data is often sparse and grounded in individual interpretation. As such, function-based design tools can benefit from automatic function classification to increase data fidelity and provide function representation models that enable function-based intelligent design agents. Function-based design data is commonly stored in manually generated design repositories. These design repositories are a collection of expert knowledge and interpretations of function in product design bounded by function-flow and component taxonomies. In this work, we represent a structured taxonomy-based design repository as assembly-flow graphs, then leverage a graph neural network (GNN) model to perform automatic function classification. We support automated function classification by learning from repository data to establish the ground truth of component function assignment. Experimental results show that our GNN model achieves a micro-average F1-score of 0.617 for tier 1 (broad), 0.624 for tier 2, and 0.415 for tier 3 (specific) functions. Given the imbalance of data features and the subjectivity in the definition of product function, the results are encouraging. Our efforts in this paper can be a starting point for more sophisticated applications in knowledge-based CAD systems and Design-for-X consideration in function-based design.

A machine learning approach to estimate product costs in the early product design phase: a use case from the automotive industry

The management and controlling of product costs play an important role in the early stages of value creation, since 70 - 80 % final product costs are determined in product development and design processes. Traditionally, the focus in business practice is often on the organizational controlling unit that records the corresponding costs when they occur. In those, later phases of the product lifecycle, the possibilities of exerting influence are very limited. Consequently, an accurate estimation of costs in the early design phase is an important instrument to support strategic decisions in the product engineering process. An intelligent approach based on machine learning to support cost management in the early design stage is presented. In a real-world case study using wheel cost data from a large original equipment manufacturer (OEM) we investigate the performance of a cross-validated machine learning framework using a greedy sequential forward feature selection method for dimensionality reduction, as well as grid search hyperparameter tuning in order to compare six regression algorithms. The results of the study show that it is possible to predict the costs of product components in the early design phase with an R2 of 0.960 using only seven features coming from the product design and development department. By a cluster analysis and scatter plots of prediction accuracies it is shown where the deviations in cost estimation come from. The study supports the statement that machine learning models are a promising instrument for product managers and cost engineers.

A fuzzy rough number-based AHP-TOPSIS for design concept evaluation under uncertain environments

Design concept evaluation in the early phase of product design plays a crucial role in new product development as it considerably determines the direction of subsequent design activities. However, it is a process involving uncertainty and subjectivity. The evaluation information mainly relies on expert’s subjective judgment, which is imprecise and uncertain. How to effectively and objectively evaluate the design concept under such subjective and uncertain environments remains an open question. To fill this gap, this paper proposes a fuzzy rough number-enhanced group decision-making framework for design concept evaluation by integrating a fuzzy rough number-based AHP (analytic hierarchy process) and a fuzzy rough number-based TOPSIS (technique for order preference by similarity to ideal solution). First of all, a fuzzy rough number is presented to aggregate personal risk assessment information and to manipulate the uncertainty and subjectivity during the decision-making. Then a fuzzy rough number-based AHP is developed to determine the criteria weights. A fuzzy rough number-based TOPSIS is proposed to conduct the alternative ranking. A practical case study is put forward to illustrate the applicability of the proposed decision-making framework. Experimental results and comparative studies demonstrate the superiority of the fuzzy rough number-based method in dealing with the uncertainty and subjectivity in design concept evaluation under group decision-making environment.

Stress and Strain Analysis of Plywood Seat Shell

In this paper, the stress and strain analysis of common laminated wood seat shell is performed. Experimental stiffness evaluation is conducted by measuring displacement of the point on the backrest, and experimental stress analysis is carried out by tensometric measuring at the critical transition area from the seat to the backrest. Finite element analysis is carried out layer by layer with a “2D linear elastic model” for orthotropic materials. Good matching is found between numerical and experimental results of displacement. It is also shown that the results of the principal stress in the measurement points of the seat shell compare favourably with experimental data. The applied in-plane stress analysis of each individual veneer is not applicable for interlaminar stress calculations that are a significant factor in curved forms of laminated wood. Curved forms of laminated wood products require more complex numerical analysis, but the method can be used to achieve approximate data in early phase of product design.

Recent Developments in Multi-disciplinary Applications of Stamping Simulation

Traditionally stamping simulation has focused on assessment of manufacturability at early product design phase and for process validation at the downstream phase. In the recent years, there has been an increasing trend towards expanding the scope of stamping simulation to integrate with other CAE domains such as structural CAE, composite materials, fatigue, safety, optimization, CFD, casting and lately 3D printing. The enablers are, highly streamlined graphical user interfaces for modeling and visualization combined with accurate, robust and scalable multi-physics solvers. In this talk, industrial case studies are presented on topography optimization and initialization of sheet metal parts with manufacturing results to improve structural stiffness, process optimization of complex stampings via highly scalable and accurate explicit analyses, topology optimization and manufacturability of stamping die structures, and thermo-forming of composite materials.

Towards a human factors and ergonomics integration framework in the early product design phase: Function-Task-Behaviour

Considering the existing methodologies’ hysteresis and cost of the human factors and ergonomics (HF/E) integration in the design phase, this paper attempts to develop a time-saving, less expensive and standard approach for designers to integrate the HF/E from the early design phase. In this study, the HF/E information is embodied by a user manual, which will be continuously improved with the refinement of design. A Function-Task-Behaviour framework is proposed to restate the design process, which involves three steps: (1) Functional specification involves function definition and decomposition according to initial user manual and other requirements; (2) Embodiment refers to conducting task definition and planning to achieve the intended function. SysML is used for task definition and PERT method is applied for task planning; (3) Detailed design refers to the interactions analysis between user’s behaviour and product’s behaviour in the work area. A case study is shown at the end of this paper to illustrate the feasibility of the proposed method in integrating the HF/E from the early design phase to improve the final performance of both product and user.

A bijective soft set theoretic approach for concept selection in design process

ABSTRACTThe problem of decision-making in an uncertain environment during early design stages has found paramount importance in recent years. A novel method based on soft set theory is developed and proposed here, for concept selection during the early phase of product design. The advantage of soft set theory to describe the features of an object through any approximations is used in the proposed method to incorporate qualitative judgements of decision-makers. Bijective soft sets are used in the proposed work to depict mapping between customer requirements and generated design concepts. The method proposes the construction of a correlation table from a bijective soft set in a parametric sense. Correlation table helps the designers to identify the effect of conflicting requirements of different customers. The union and intersection operations are then performed on the correlation table which are called here as Row Union (RUnion), Row Intersection (RIntersection), Column Union (CUnion), and Column Intersection (CIntersection). A RUnion and CUnion operation on correlation table helps the designer to identify all the potential concepts which are suboptimal choices based on customer requirements. After performing RUnion and CUnion operations, RIntersection and CIntersection are performed to identify optimal choice(s) which could meet maximum conflicting requirements of customers.

Enabling Non-expert Sustainable Manufacturing Process and Supply Chain Analysis During the Early Product Design Phase

Consumers are pressuring companies to produce products with superior sustainability performance, yet educators are disadvantaged in training students about sustainable engineering and many engineers are often not well-positioned to perform product sustainability assessments. In particular, quantifying environmental impacts is a key aspect of achieving improved product sustainability performance that has garnered much attention over the past two decades, but tools remain deficient to assist manufacturing decision making. In light of efforts undertaken to develop sustainability assessment methodologies, we review recent developments in quantifying a widely adopted environmental performance metric, carbon footprint, in manufacturing processes and supply chain networks. We also present a methodology to address the deficit identified from this review for simple, easy-to-use sustainability assessment methods and tools. We suggest a questionnaire-based methodology to provide non-experts with a better understanding of sustainability performance, specifically during the product design phase. An application of the methodology is demonstrated to quantify and compare environmental impacts for the production of two quadcopter upper shell designs. The review presented can help the sustainable design and manufacturing community in identifying research gaps, while non-expert engineers and engineering students can benefit from application of the presented methodology in learning and in practice.

Product life cycle management approach for integration of engineering design and life cycle engineering

AbstractOptimized lightweight manufacturing of parts is crucial for automotive and aeronautical industries in order to stay competitive and to reduce costs and fuel consumption. Hence, aluminum becomes an unquestionable material choice regarding these challenges. Nevertheless, using only virgin aluminum is not satisfactory because its extraction requires high use of energy and effort, and its manufacturing has high environmental impact. For these reasons, the use of recycled aluminum alloys is recommended considering their properties meet the expected technical and environmental added values. This requires complete reengineering of the classical life cycle of aluminum-based products and the collaboration practices in the global supply chain. The results from several interdependent disciplines all need to be taken into account for a global product/process optimization. Toward achieving this, a method for sustainability assessment integration into product life cycle management and a platform for life cycle simulation integrating environmental concerns are proposed in this paper. The platform may be used as a decision support system in the early product design phase by simulating the life cycle of a product (from material selection to production and recycling phases) and calculating its impact on the environment.

Improving sustainability performance in early phases of product design: A checklist for sustainable product development tested in the automotive industry

In the early phases of product development, it is important to both reduce costs and improve a product's sustainability performance. Insufficient data are available on the costs and sustainability aspects of innovative concepts such as automotive lightweight design, which require the application of new materials and processes. The lack of information and high degree of uncertainty hinder the use of traditional sustainability evaluation tools such as Life Cycle Assessment during these early phases. Tools used in eco-design and sustainable design have disadvantages since they either focus on only one sustainability dimension, require quantitative data about materials and processes, or cannot be applied by designers and engineers. To overcome these disadvantages, a new checklist for Sustainable Product Development (CSPD) was developed in close collaboration with practitioners. The CSPD allows the qualitative assessment of environmental, economic and social aspects during the early phases of product development while considering a full life cycle perspective. It provides the methodological foundation for an iterative process, in which improvement tasks related to sustainability are defined that must be completed by the engineers. The applicability of the CSPD with reference to a wide range of technologies was evaluated and tested in a case study that included nine automotive lightweight technologies. This case study revealed that the developed tool helped designers and engineers assess and improve the sustainability performance of a technology and that it stimulated processes of collaboration and information exchange within and between organizations.

A discussion on new necessity-based method for requirements list elicitation and requirements classification

Establishing appropriate requirements is essential in early phases of product design for obtaining enough information and in order not to over-constrain the product. Consequences of failing to do so are discussed. An overview of state-of-the-art methodologies for eliciting and classifying requirements is presented. Existing elicitation methods tend not to focus on the requirements content and the classification methods overlook the missing requirements. To overcome this gap a new method for requirements elicitation and classification is proposed. It defines the universally necessary requirements, product- specific necessary requirements and optional requirements. The appropriateness of the method is verified with a case-study on air ventilation register box and expert opinions. The positive contribution of the method is confirmed through evaluation with novice design engineers.

Product lifecycle management approach to design a product and its optimised supply chain

This paper deals with two major issues for current manufacturing organisations: the product design and the supply chain design. These problems are usually solved separately, but in recent years, approaches were proposed to tackle these two issues together. Integrating product and supply chain optimisation is relevant. Indeed, the design decisions made in the early phases of product design will have significant impact upon future manufacturing and logistical activities. In this paper, we investigate more precisely the role of product lifecycle management (PLM) as an integrating element and a supply chain optimiser. PLM is a business strategy that aims to collaboratively manage the product centred activities during the whole product lifecycle and through the extended enterprise. In fact, PLM enables a supply chain to become much more competitive by an effective collaboration among all its partners throughout the product lifecycle, particularly, their involvement in the early phases of product design. We propose a methodology based on PLM approach to design simultaneously the product and its optimised supply chain.

Product Form Design Using Virtual Hand and Deformable Models

This paper presents a computer-aided conceptual design system for product form design. This system integrates the virtual hand, which is manipulated by product designer, with deformable models representing the product forms. Product designers can use gestural input and full hand pointing in this system to discover potential new ways for product form design. In the field of industrial design, styling and ergonomics are two important factors that determine a successful product design. Traditionally, designers explore possible concepts by sketching their ideas and then using clay or foam mock-ups to test them during the early phases of product design. Within the proposed system, deformable modeling technique is integrated to provide a useful and efficient tool is provided for product designers that enable to produce product form proposals efficiently without unnecessary trial and error. Designers can input 3D scanning data or a 3D CAD model as an initial prototype. Then, the input model is given the material’s elastic property via the construction of a volume-like mass-spring-damping system. The virtual hand in the system constantly changes gestures as the designer manipulates it with a glove-based input device. The product form will be deformed or shaped according to the amount of force exerted by the virtual hand. A mesh smoothing technique called “PN-triangle” is also used to improve the appearance of the deformed model. Finally, a physical prototype with volume and weight is generated using a rapid prototyping machine. Designers can use these mock-ups to conduct further ergonomic evaluations.

Identifying Risk at the Conceptual Product Design Phase: A Web-Based Software Solution and Its Evaluation

This paper introduces a web-based application that enables engineers or designers to identify risks during the conceptual phase of a product design. This software application was developed based on the Risk in Early Design (RED) method developed by Author, Stone, and Tumer. The RED method demonstrates that risks can be identified in the early phase of product design by relating recorded historical failure information to product functions. Based on the concept of RED theory and current industry needs, the goals of a web-based RED application were defined. These goals are the intended benefits or functionalities that the web-based RED application would provide. In addition, a multi-level evaluation framework was adopted to determine how well the application meets the needs of various organizations. As part of the evaluation, a questionnaire was developed and administered to a sample industrial and academic user group. The results of the evaluation indicate that the web-based RED software application meets many of the goals to help an organization in performing product risk analysis.

Dealing with subjectivity in early product design phase: A systematic approach to exploit Quality Function Deployment potentials

Quality Function Deployment (QFD), as a customer-driven tool, is generally used in the early phase of new or improved products/services design process, and therefore most of the input parameters are highly subjective in nature. The five major input components of the QFD, which are laid in the House of Quality (HOQ), namely, the customer requirement, the technical attribute, the relationship matrix, the correlation matrix, and the benchmarking information, play a central role in determining the success of QFD team. Accurate numerical judgment representations are of high importance for the QFD team to fill in the values of each of those components. In this paper, a generic network model, based on Analytic Network Process (ANP) framework, will be proposed to systematically take into account the interrelationship between and within those components simultaneously and finally derive their relative contribution. In particular, with respect to a rapidly changing market, the incorporation of the new product development risk, the competitors’ benchmarking information, and the feedback information into the network model may be considered as a novel contribution in QFD literature. Not only does this network model improve the QFD results’ accuracy, but it also serves as a generalized model of the use of ANP in QFD with respect to the previous research. A simple illustrative example of the proposed network model will be provided to give some practical insights.

The use of virtual prototyping and simulation in ITER maintenance device development

Virtual prototyping technology has become a very valued tool in the early phases of product design. The use of virtual technologies is of special interest in the development of the ITER maintenance devices, mainly due to the large costs, sizes and complexity of physical prototypes. This paper shows how virtual prototypes are built and implemented in simulation tools, which are then used to develop the design of the maintenance equipment. Two applications are presented. The first case concerns the controllability of the water-hydraulics servo-actuators of the cassette mover. In the second application, a bilateral teleoperation architecture is designed to remotely control a robot manipulator. The resulting designs are going to be transferred, in a later phase, to a full-scale prototype facility (Divertor Test Platform 2).

Product cost estimation model in early design phase based on cost cluster

A cost estimation model based on cost cluster is presented with big samples in early product design phase be-cause precise cost estimation in early adptive or derivative product design phase is very difficult. Euclidean distance be-tween samples and estimating product are calculated to express their similarity. Difference matrix, distance matrix and similar-ity matrix are built base on euclidean distance sets between samples and indeterminate estimation product, then most corre-lated sample sets are selected to get interval of estimated cost based on cost cluster analysis. An example of brake disc shows invalidity of the cost cluster model. The result of experiment proved that cost cluster model was able to separate relative order of qulity of the samples.