A methodology for extracting dimensional requirements for a product from customer needs (original) (raw)
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2009
Since the last decade, considering the globalization process of the economy, the market evolution has tended to reduce product costs and to decrease time devoted to the product design and development. In this context, it is also important to consider the growing need for improving product performance and for integrating user specifications very early in the design process. In order to answer these needs, this paper proposes a specific design method based on Axiomatic Design methodology and a functional analysis in order to reduce the time dedicated to routine engineering. This method is directly integrated into our self-developed PLM system-Product Lifecycle Management-in order to work in a worldwide and collaborative design environment. The main objective of our methodology is to define the CAD model geometry according to the modifications and the customer needs. In order to manage such control, we can identify functional parameters and functional rules through the functional requirements and the input constraints. Moreover, we can extract the specific parameters and the specific rules from the older CAD models stored in the Product Data Management system or PDM from the previous and validated project. Our method explains how to obtain and link the different parameter types and rules through the definition of a theoretical Functional Knowledge which relates a 3D geometry entity to a customer need. This knowledge aims at giving an input to a knowledge management system. It also defines a specific architecture of the 3D CAD product based on the system components divided in functional entities. This specific architecture is used in order to perform and lay the foundation of a Knowledge-Based Engineering methodology or KBE. Moreover, this specific CAD architecture gives us a possibility to develop our data mining methods which are included into our KBE approach.
Product Modeling, Evaluation and Validation at the Detailed Design Stage
Proceedings of the Canadian Engineering Education Association, 2011
The expansion of the markets corroborated with product customization and short time to launch the product have led to new levels of competition among product development companies. To be successful in the globalization of the markets and to enable the evaluation and validation of products, companies have to develop methodologies focused on lifecycle analysis and reduction of product variation to obtain both quality and robustness of products. This paper proposes a new design process methodology that unifies theoretical results of modeling stage and empirical findings obtained from the validation stage. The evaluations and validations of engineering design are very important and they have a high influence on product performances and their functionality, as well on the customer perceptions. Given that most companies maintain the confidentiality of their product development processes and that the existing literature does not provide more detailed aspects of this field, the proposed methodology will represent a technical and logistical support intended for students or engineers involved in academic as well as industrial projects. A generic methodology will be refined based on a new approach that will take into consideration the specification types (quantitative or qualitative), the design objectives and the product types: new/improved, structural/esthetic. Hence the new generic methodology will be composed of specific product validation algorithms taking into account the above considerations. At the end of this paper, the improvements provided by the proposed methodology into the design process will be shown in the context of the engineering student capstone projects at the Université de Sherbrooke.
International Journal of Decision Sciences, Risk and Management, 2015
Product development is the process of bringing a new product to market. Quality function deployment is a product development tool to improve customer satisfaction, design the product quality and enhance competitiveness of the company in the market. In developing new products, we capture the requirements from the customer, and return it to the customer as a new product. Requirements and customer's language might be imprecise, causing inconsistent studied results and deviating of the voice of customer. These generally cause failure of a product development project. To improve quality in product development process, fuzzy set theory is employed in the product development phases. This model focuses on customer requirements and on engineering characteristics. The correlation between engineering requirements and benchmarking analysis, often ignored in most of QFD researches, are considered. Aiming to solve these problems, this paper aims to improve the precision of QFD first phase, and optimise and develop the customer requirements approach to reduce risks in subsequent phases.
2011
In general, it is difficult to select a satisfactory product concept because the information in the early stage of design process is subjective, qualitative, and even uncertain to design engineers. The correlations among engineering characteristics for a product concept also increase the complexity of conceptual design. Moreover, it becomes important to consider not only customer requirements but also product lifecycle requirements. In spite of these problems, the resources that can be allocated in the product development are limited so that a company should select the most satisfactory product concept within its available resources. Therefore, it is useful to develop a new method for efficiently supporting conceptual design under this complex design environment. To this end, this study proposes a decision support method with extended house of quality (HOQ). With the proposed method, the best product concept and the associated investment allocation can be decided concurrently under consideration of product lifecycle factors and resource constraints. As a mathematical model combined with the extended HOQ, a mixed integer nonlinear programming model is defined and three heuristic search algorithms are developed. To show the usefulness of the proposed algorithms, a case study and computational experiments are introduced.
A Requirement-Driven Product Development Process
2004
Product development is often described as an iterative process of finding solutions that match specific requirements. The many dimensions of this process include time, organization, product-specific elements such as the level of abstraction and detail, and analysis to verify the product's properties. Many types of software tools are used to generate and visualize the concept shape. These include CAD (computer-aided design) tools; tools to simulate and verify product properties, such as FE (finite element analysis) and MBS (multibody systems); and tools for handling product data such as PDM (product data management). This paper focus on the effective use of simulation software such as FE and MBS tools to support the process of verifying that a product meets the formulated requirements. The simulation software can be used for such things as selecting alternative solutions or as a final check or optimization of a solution concept. Its can be used even more effectively if it is supported by a framework for handling the information created during the verification process. This paper presents a proposal for an information framework that can support traceability and reuse of partial results created during the verification of a specific required attribute. This framework also facilitates study of the effects of changes in the specification on product properties. The framework is illustrated in a modeling and simulation scenario for a lifting unit on a wheel loader produced by Volvo CE. This scenario focus on modeling and simulation activities and how these can be supported in a question-and-answer driven process that investigates the behavior of the lifting unit.
Towards the routinisation of engineering analysis to support product design
International Journal of …, 1999
While it is generally agreed designers would like to benefit more from analysis, methodologies are lacking for identifying appropriate analysis models and transforming them into readily usable tools. This paper identifies designer needs regarding analysis of physical behavior, and introduces the term "routinization" to describe the process of creating automated analysis modules that can be regularly used in product design. A routinization process is presented with electronic packaging examples. Based on the multirepresentation architecture design-analysis integration strategy, this process creates catalogs of product model-based analysis models (PBAMs)-analysis modules that associate design data with analysis models to obtain results in a highly automated manner. Routinization is illustrated using a PBAM for printed wiring board warpage analysis from the TIGER project. Other electronic packaging applications such as solder joint fatigue are highlighted. Design inputs come from STEP product models and solution methods range from encoded formulae to multi-vendor finite element analysis. Observations are given, including how routinization is a knowledge capture technique that aids both engineering analysts and product designers. While it transforms the research of the analyst into tools for the designer, it serves as a catalyst that reveals new problems for the analyst to tackle. KEYWORDS computer aided design (CAD), computer aided engineering (CAE), constraint schematic, design-analysis integration (DAI), multi-representation architecture (MRA), routinization NOMENCLATURE ABB analysis building block APM analyzable product model DAI design-analysis integration MRA multi-representation architecture PBAM product model-based analysis model PWB printed wiring board PWA printed wiring assembly (a PWB populated with components) SMM solution method model Ψ ABB-SMM transformation Γ idealization relation between design and analysis attributes Φ APM-ABB associativity linkage indicating usage of one or more Γ i
Requirements Engineering, 2008
This paper reports results of research into the definition of requirements for new consumer products––specifically, electro-mechanical products. The research dealt with the derivation of design requirements that are demonstrably aligned with stakeholder needs. The paper describes a comprehensive process that can enable product development teams to deal with statements of product requirements, as originally collected through market research activities, in a systematic and traceable manner from the early, fuzzy front end, stages of the design process. The process described has been based on principles of systems engineering. A case study from its application and evaluation drawn from the power sector is described in this paper. The case study demonstrates how the process can significantly improve product quality planning practices through revision of captured product requirements, analysis of stakeholder requirements and derivation of design requirements. The paper discusses benefits and issues from the use of the process by product development teams, and identifies areas for further research. Finally, the conclusions drawn from the reported research are presented.
Arxiv preprint arXiv:0905.0775, 2009
The great majority of engineered products are subject to thermo-mechanical loads which vary with the product environment during the various phases of its life-cycle (machining, assembly, intended service use…). Those load variations may result in different values of the parts nominal dimensions, which in turn generate corresponding variation of the effective clearance (functional requirement) in the assembly. Usually, and according to the contractual drawings, the parts are measured after the machining stage, whereas the interesting measurement values are the ones taken in service for they allow the prediction of clearance value under operating conditions. Unfortunately, measurement in operating conditions may not be practical to obtain. Hence, the main purpose of this research is to create, through computations and simulations, links between the values of the loads, dimensions and functional requirements during the successive phases of the life cycle of some given product. The methodology presented is organised in three successive steps. Firstly, a functional requirement is chosen by the user, and the corresponding dimension chain is extracted from the Computer Aided Design (CAD) model. In order to be independent from the design parameters set by the designer, this paper uses the TTRS (Technologically and Topologically Related Surfaces) concept to relate the functional surfaces within a given dimension chain to some corresponding functional requirement at the manufacturing and assembly phase of the product life-cycle. Practically speaking, this leads to the definition of a set of nominal dimensions that serve as a baseline for the subsequent phases of the product life-cycle. The second step consists in calculating the strains on the parts under thermo-mechanical loads in operating conditions. Generally this will be done using Finite Elements Analysis (FEA) or existing theoretical formulations. As this stage of the method uses existing techniques, the authors will use the simulation results as they are. Thirdly, for each part of the product, the dimensions mentioned in the first step are adjusted with the results of the second step and introduced in the dimension chain. This, in turn, leads to a predictive value of the functional requirement under load. In the end, the complete methodology will provide the user with an account of the evolution of the functional requirement variation, across the main phases of the product lifecycle. Interestingly, these variations will add on top of the allowed manufacturing errors, as specified by the geometric dimensioning and tolerancing annotations from the initial design phase of the product life-cycle. From an implementation point of view, the variations of the loads, temperature and dimensions will be expressed as intervals and will be associated to the parts and dimensions using attributes in the TTRS model. Furthermore, in order to be independent from the CAD software, the research will use STEP to represent 3D solids. The paper concludes with the presentation of a practical application of the above methodology on a simple, one dimension crosshead guide example.