Ijodir 2010 / Vol.5 - n°3
Design optimization under evidence based uncertainty with application to an engine connecting rod
Authors: S. Segonds, C. Gogu, Y. Qiu, C. Bes and A. Mauffrey
Institution: Université de Toulouse (France)
Abstract: Optimization in design is becoming increasingly popular in the field of mechanical engeering. A further step concerns the taking into account manufacturing variability during the initial phases of design optimization. A methodology for design optimization under uncertainty is proposed here. Classification of uncertainties is listed and a propagation method for epistemic uncertainty based on the interval theory is presented. Then this method is applied to the design determination of a connecting rod taking into account the uncertainty due to the re-fitting procees of the die cast. The design of two specific parameters is studied. Results are discussed before concluding.
Keywords: design optimization, design under uncertainty, Dempster-Shafer theory, engine connecting rod
The significance of form elements: A study of representational content of design sketches
Authors: S. Z. Abidin1,3, A. Warell 2, A. Liem 3
Institutions: 1Universiti Teknologi Mara (Malaysia), 2Lund University (Sweden), 3Norwegian University of Science and Technology (Norway)
Abstract: The purpose of this paper is to understand the significance of form elements through the interpretations of design sketches. These interpretations are provided by designers themselves interpreting expressive characteristics of car images, and by students interpreting the sketches of designers’ morphing sequences. In the experimental investigation of the sketching process through morphing sequence exercises, designers used individually driven styles and approaches when creating product form. These approaches produce characteristically different form ideas, which differ (but also show consistency) with respect to type of car category, expression, identity, recognition, format, composition, complexity, etc. Typically, assessment of generated sketch work and ideas is done using relative heuristic evaluation in a comparative design review. Given a large set of automotive sketches, general patterns of styling emphasis can be identified. The paper concludes that perceptions of designers are varied due to the representation format of the ideas as visual hand sketches. The visual hand sketches point out certain meaning and can be categorized with respect to perceptual characteristics according to the Product Perception Framework (PPE framework) and suggest that a tool to support evaluation and generation of early design concepts can be developed, and to support the generation of form ideas with desired characteristics for a brand, product category and market.
Keywords: aesthetics, categorization, form, perception, visual
Study of consumers’ functional and affective needs towards make up: helping innovation
Authors: J. Morel, H. Di Martino, A-M. Pensé-Lhéritier
Institution: EBI (France)
Abstract: Developing new products or concepts should not be solely about carrying out tests and analysing results. It should rely on knowing what the consumer consciously expects from the functional specifications of the product, but also on the subconscious expectations that may impact its emotions or well-being. The following study on make up was designed to understand young women’s functional and affective needs towards the expected make up effect. Better insights of the functional attributes of make up were acquired using a Kano questionnaire. Then, with the help of salivary markers and a self-esteem questionnaire, modifications of the affective state in response to sensorial stimuli, more specifically here a change in the facial appearance, have been demonstrated. Thus, with the objective of assessing the expectations in terms of product functionality as well as the impact on the consumer’s well being, the following study has allowed showing the use of the various tools used
Keywords: make up, well-being, sensory attributes, innovation, Kano, salivary markers.
A Behavioural Design Approach to Improving Mechanical System Design with Integration of Use Conditions
Authors: R. Houssin1,2, H. Sun1,2,3, M. Gardoni1,4
Institutions: 1INSA Strasbourg (France), 2University of Strasbourg (France), 3Jilin University (China), 4ETS Montréal (Canada)
Abstract: Mechanical system design is usually performed simply taking into consideration system functions and structures, while users’ behaviours in terms of using the system are generally not fully considered during the early design phase. Specific use conditions are also usually not taken into account. Use conditions refer to all parameters that could influence the performance of the system when it is used by the end-user. This paper covers multi-trade mechanical system design, and aims to better integrate system-use conditions into system behaviour, starting from the early design phase. To that end, a global view of behavioural design approach is proposed as a feasible solution to improve system performance starting from the early design phase, and a model of the use task (performed by the user or by the system itself) required to realize the mapping of the behavioural design approach is also proposed.
Keywords: design method, behavioural design, use conditions, task, user behaviour, structure behaviour.
The use of early design tools in engineering processes: a comparative case studies
Authors: F. Segonds1, M. Iraqi-Houssaini2, L. Roucoules2, P. Véron2, A. Aoussat1
Institutions: 1Arts et Métiers ParisTech, Paris (France), 2Arts et Métiers ParisTech, Aix-en-Provence (France)
Abstract: Nowadays, product design is increasingly complex: not only must it answer customer needs through complex functions; it must also ensure traceability throughout the design process, keeping in mind that standards and stringent regulations must be complied with. Faced with new challenges, engineering practices have evolved to allow stakeholders to be able to manage projects in new work environments, especially during the early stages of design. After presenting a state of the art of early design tools used in product design and their integration in PLM context, we compare class diagrams for two of them : TDC software (Knowllence©) and RFLP module of CATIA V6 (Dassault Systems©). Then, our paper presents an experiment focusing on these tools, which aims to assess their usability, to evaluate and compare them. Users can raise issues, take note of which functionalities are appreciated, and provide qualitative feedback. We analyze the results obtained in this experiment and propose a comparison based on four topics: learnability, satisfaction of users, efficiency and error correction. Finally, we present some links between class diagrams and usability of the tools.
Keywords: early stages of design, software usability, interoperability, PLM.
