Carole Bouchard
email: carole.bouchard@paris.ensam.fr

A Aoussat

Design process perceived as an information process to enhance the introduction of new tools

Keywords: computer aided design tools, design process, information process

Our research adds its weight to collaboration between companies and the research laboratory in conceiving new products (CPN/ENSAM Paris). Our work focuses on industrial design, creativity and innovation. In this paper we have formalized the design information process to build new tools of communication, decision-making and creativity for the different players in the design process.

General Introduction

Today, the design process of industrial products has been transformed both by earlier computerization and production of design information aimed at clari®cation and memorization of the earliest phases such as marketing, design, etc.

This evolution is based on the context of variety and reaction capability de®ned by Midler [START_REF] Midler | L'Auto qui n'existait pas[END_REF] where initial phases are modi®ed by both inter-professional synergy which takes place increasingly earlier in the process and by the introduction of new digital tools especially in the early phases of design projects. We believe that the introduction of new digital tools must be based on improved formalization of the early phases in the design process. In this respect, the design process can be seen as an information production process, i.e. a set of successive cycles of design information with the manipulation of an increasing number of concrete representations of physical objects to reach the Final Solution, with a problem space being set in a solution space for each cycle. Results in this paper involve the formalization of input data as intermediate representations from the technical speci®cations. Indeed, the design process can be seen as an information process where the design problem space will be gradually transformed into a solution space.

Modelling the information process in design

Finalized intangible information is transformed step by step into tangible information by way of mental representations (transfer of information: shaded area). Birtley [START_REF] Birtley | Rapport Interne de Recherche[END_REF] proposes a generalization of the theory of information: `information is what forms or transforms a representation'. A comparison can here be made between the transformation of images and the representations generated by messages containing information. The information modi®es the representations so communication can be measured by measuring these changes. A physical system supplies an external memory modifying the problem of perception in a decisive way. The space issue (expressed goals), together with the solution space (physical representations), are given precision by the production of signs ± verbal codes in the case of briefs and formal codes in the case of solutions. Each cycle ± Brief1, m1 and M1 ± matches a state of representation. The evolution of the Brief is de®ned by the transformation of ends into purposes, purposes into objectives, objectives into criteria, the criteria as increasingly concrete technical speci®cations. Mental representation corresponds only partially, like the physical model.

By de®ning models within a set of attributes, process P is characterized by the following succession of cycles: Brief1 M1 (A11, A12, A1n), Brief2 M2 (A21, A22, A2n) and BriefNMN (An1, An2, Ann) 1 . The process develops a system of information (objectives) in a signs system (solutions) in which recognition and evaluation enable the production of new signs. Signs emanate from the process of the mental make-up of an imaginary object being changed into an easily comprehensible object. The design process ®ts into the general plan of the process of conception presented above. The solution space, in the context of the activity of design, is especially marked by the changeover of iconic signs to plastic signs. The solution space is established by a succession of modelled forms. Thus, the diachronous design process is characterized by the gradual overall recon®guration of a space problem (brief) into a space solution (3-dimensional model), according to a recursive cycle in which partial transformation takes place from the space problem to intermediate solution spaces at every representation level. At any time in the process, designers must be able to assimilate and deal with a large volume of information without losing sight of objectives. This equivalence characterizes the problem/solution space. The design process consists in reducing abstraction through the use of various successive levels of representation integrating increasingly numerous constraints. It is characterized by Wang as concepualization including an iterative cycle of mental solutions shown with a given problem [START_REF] Wang | An Approach to Computer-Aided Styling[END_REF], where (1) the selection of a solution or partial solutions enable the limitation of uncertainty, and keeping in mind the necessary level of vagueness in modi®cations during subsequent phases [START_REF] Lebahar | Le Travail de Conception en Architecture: Contraintes et Perspectives Apporte es par la C.A.O[END_REF], (2) new constraints are then added by preserving shape and initial ideas, with (3) the display of a new physical representation generating new ideas and new solutions. Lloyd and Scott describe the design process as generative, deductive and evaluative statements in the activity of design [START_REF] Lloyd | Discovering the Design Problem[END_REF]. We consider the design process can be based on the three following phases:

Generation phase

This phase consists in the generation of new ideas and new solutions: by means of numerous mental images and from brief data and other information contained in any design project, designers can generate physical representations and physical solutions as 2-dimensional and 3-dimensional models.

This requires the use of manual or digital tools, depending on designer skills and on corporate culture. This phase can be performed in accordance with various `trends analysis' and `applied creativity' methods. Trends analysis enables formalization of formal attributes linked to particular environments before the early sketching phase. Applied creativity enables the generation of a large volume of ideas, possibly even including the points of view of other non-designer players (ergonomists, engineers, etc.). The generation phase is an open phase.

Information phase

Designers and other players in the design process integrate many categories of information that will be gradually formalized as design solutions throughout the design process. This represents the information contained in the brief and emanates from sources of inspiration and data researched by the designers to complement the brief.

According to Prost, the choice of constraints is furthermore a process fundamental to the activity of design [START_REF] Prost | Conception Architecturale, Une Investigation MeÂthodologique[END_REF]. The information and data integrated by the designer can be categorized into information connected to the project, passed on by other players or sought by the designer and the designer's own information or that stemming from the designer's interactions with the surrounding world (notions of references as in¯uences and sources of inspiration) and sometimes dominating over the information connected to the problem. This is both an open and closed phase.

Evaluation and decision phase

The choice of the right design solutions to be developed physically is achieved by an evaluation and deduction process. It uses criteria from the initial or reviewed brief to help choose the best solutions. The Evaluation and Deduction phases are analytical phases. Many methodological tools can back up these phases such as functional analysis and semantic differentiation. This phase is a closed phase.

Quality Function Development and Functional Analysis allow the generation of functional criteria linked to the primary main functions and the secondary constraints functions. These criteria can be quanti®ed and used during the evaluation of many solutions in order to record them and select the ®nal solution(s).

Designers and non-designers do not posses the same differentiation capability [START_REF] Smets | Expressing Tastes in Packages[END_REF]. Semantic differentiation or semantic mapping is another evaluation/prediction model determined by a visual evaluation of the image of products. It consists of a full representation of the product space produced as per two highly distinguishing semantic axes. The semantic differential establishes a quantitative relationship between the Shape of the product (dimensions) and the evaluation of its signi®cance according to semantic attributes. Application of semantics helps designers to understand and evaluate their own communication models. Communication is successful by matching the response to the signal. Most industrial designers feel that they control the process. They know what they wish to say and are certain that they have the tools to make the correct visual statement. Unfortunately, little time is spent for the understanding of the remaining two components of the scenario reception and response and this is where the breakdown usually occurs.

Description of an information cycle

All information cycles contain an informative phase, a generative phase and a decision-making phase (evaluation-selection) whose outcome is an intermediate representation that will be used for the transmission of project information to the other design process players and ± compared with the previous cycle ± as a more concrete informative mass.

The ef®cacy of each phase will in¯uence the whole process and the three phases should be of equal value to achieve optimal results. If one of them fails, the general process and of course the ®nal result will fail. Currently, software is being assessed to assist designers in the digital realization of the three phases. One advantage would be the possible memorization of the project design data and another the possibility of achieving fast modi®cations capable of being transmitted to and printed by consumers physically in quasi real time. For the information phase, numerous digital iconic Databases are available. For the generation phase, Computer Aided Design systems are being introduced or more recently, purpose-built automotive Computer Aided Styling systems. The latter will be presented in this paper for their relevance to design, the purpose of our study.

Description of the general information process

Formal and informal information used in the design process is increasingly formalized on a individual or group basis in the form of verbal transcriptions, mapping or modelling and then as successive project syntheses. These various forms 3 Current situation of digital tools in design process

Description of conventional styling

Design problems are characterized by the simultaneous building of problems and solutions, complicated by incomplete data and a great variety of solutions. The design process reduces abstraction by the use of many representation levels including an increasing number of constraints. In the above process, shape is more important than measure. The designer seeks the best shape, the best idea and then integrates measurement constraints. After preliminary sketches, many general solutions do not apparently lose their relevance. The selection of solutions or partial solutions allows the limitation of uncertainty, bearing in mind the blur level necessary to permit modi®cations in the next stages [START_REF] Lebahar | Le Travail de Conception en Architecture: Contraintes et Perspectives Apporte es par la C.A.O[END_REF]. New constraints will then be added while retaining the initial general shape and idea. The visualization of a new representation level will generate new ideas for new solutions. This kind of drawing has to be quick enough and must be con®ned to the relevant information (detail level) to solve the problem [START_REF] Lebahar | Le Travail de Conception en Architecture: Contraintes et Perspectives Apporte es par la C.A.O[END_REF]. It is necessary to have a de®nition of the needs of designers in terms of representation and to de®ne the links between a physical representation and a mental or sensorial representation mode. Drawing is the image of thought [11]. It is important to consider that other operators like consumers or engineers have to appear earlier in the design process involving border-crossing relations. Representations are a physical visual medium for the simultaneous generation of new ideas and for `structuring' (®xing thought). They are used by the designer himself and communicated and interpreted by other automotive supplier operators for transformation or by appraisers for assessment. In the design process, some steps are validated by considering their appropriateness to the brief. This allows for the necessary level of formalization for pedagogical and communicatory reasons. Each stage also means the gradual integration of new constraints (remaining creative during solution building) and the assessment by other actors of the appropriateness of the concept to the brief using the matching representation level. Evaluation in its various parts remains a critical stage: how to judge a drawing without being subjective in relation to the problem. In order to match the brief, the assessment must be achieved with respect to the image attributes and the functional attributes. But, the expressed `feeling', a word often used by designers, together with the graphical qualities and detail level (precision of thought) affect considerably the perception of these attributes. The greater the degree of formalization of possible attributes, the easier the assessment.

Main problems encountered with the use of conventional computer aided design tools

Development of new Computer Design Tools should take into account the current list of problems being compiled with conventional Computer Aided Design Tools.

The results of an inquiry in 1997 by 40 stylists (transport design specialists and students) can be summed up as follows [START_REF] Bouchard | Computer-aided Design for Car Builders[END_REF]:

. Software has to ®t traditional designer strategies ± it should not require new designer strategies. These could interfere with the `natural' designer activity, e.g. `selecting elements and linking them together', except where the matching function offers advantages.

. Association of 2-dimensional with 3-dimensional is problematic. Either the software needs a 3-dimensional form of reference to project 2-dimensional sketches using the projection approach or the modelling is dif®cult because of the low 2-dimensional sketch input, using the `free curves' approach. In design, an iterative method (sometimes with a manual modeller) should be used, ®rst in 2-dimensional, then in 3-dimensional, and so on.

. Representation requirements: the CAD monitor is not large enough to display several concepts simultaneously, or scale vehicle models. Likewise, a large screen is required to simultaneously display a global representation and a more detailed representation. This presents the dif®culty of visualizing the model and a 3-dimensional object in a 2-dimensional space. In a 3-dimensional computerized representation space it is dif®cult to assess the real position of a point in relation to its identi®cation marker.

. Manual manipulation: a direct input system with a mouse or even with an optical pencil is inaccurate because of imprecise positioning in the pointer space and because of the matching computerized line dependent on speci®c pixels. Moreover, the system response time requests that designers receive complementary training to enable their proprioceptive representation to ®t their mental image.

. Decision-making: software of this type enables early con®rmation of information from the designer.

Description of new computer aided design tools

Digital tools currently tend to participate increasingly earlier in the design process. In major companies, CAD tool interfacing currently takes place at the stage between the representation of ®nal concepts and their development. CAD tools can also be used earlier than this phase in order to produce a realistic rendering in an environment integrating colors, lights and backgrounds. Conventional digital tools such as Alias or CDRS used for the generation of computerized images are often sourced from design to engineering department information ¯ows with the aim of comparing different variants for cost before making a selection. They produce a mathematical de®nition of the design that can be directly integrated into rapid prototype producing media. Wardle states, `they eliminate the need for certain loops of model generation and consistently accelerate the activities of concurrent engineering to reduce development time' [START_REF] Wardle | Tomorrow's Designer. Combining Sensitivity with Technical Skills[END_REF]. Besides, concept variants can be compared for the purposes of selection. But interest is now being shown in the integration of CAD tools at the initial ideas and drafting stage. One result is the development of new software styling applications at the research stage. `Computer Aided Styling tools' also tend to back up the information, generative or decision-making phases. They are based on a precis analyses of designer activity, including their conscious awareness and the `conceptualization' containing an iterative cycle of mentally visualizing solutions with a given problem [START_REF] Wang | An Approach to Computer-Aided Styling[END_REF].

What is more, the design process occurs through the increasing use of co-software incorporated in a recently adopted method called Computer Aided Collaborative Work or computer supported collaborative work (CSCW), involving software packages evolving in shared environment. These tools maintain a wide vision of the work while optimizing the ratio of mutual prescription among designers [START_REF] Hatchuel | Apprentissages Collectifs et Activite s de Conception[END_REF] in situations of conceptions characterized by a strong interdependence among operators [START_REF] Beguin | Travailler avec la CAO en IngeÂnierie Industrielle : de l'individuel au Collectif dans les ActiviteÂs avec Instruments[END_REF]. Co-conception software packages favour the co-operation and co-ordination of convergent activities through careful re¯ection and fast ef®cient decision-making. This software integrates Data Basis Management systems that can be very useful for designers.

We shall here set out the most relevant design digital tools we found in European literature under the heading of Computer Aided Styling Tools. The ®rst, second and third chapters mostly deal with the generative aspect while the fourth chapter covers the evaluative part of designer activity. Some styling phases can indeed be automated to a certain degree.

The Computer Aided Styling tools we were shown in various research laboratories provide the following advantages:

. They tend to reduce the main problems quoted in }3±2, by taking into account the natural strategy of designers and facilitating the link between 2-dimensional and 3-dimensional generation, offering improved visualization and the possibility of plasticity usually provided by conventional tools in the form of `pen and paper' or `markers' but not by Conventional Computer Aided design Tools. . Some are connected to Databases allowing direct partial or full integration of 2-dimensional or 3-dimensional objects in new representations following the same process as the natural mental process of the designers when they integrate sources of inspiration in the generation of new representations.

We shall then present a case study of an investigation tool for designers aimed at facilitating their information phase work.

To conclude, we shall extrapolate current trends to explore the prospects of developing new tolls.

Computer aided styling based on morphology, interpolation and geometric transformation (project backed by tatung company and the national science council in taiwan)

This software affords computerized assistance in the investigation process by stylists. It enables the expression of much generated thinking. It can be based on a morphologic approach: the possibility of generating a large number of combinations with a systematic exploration of different architectural con®gurations of functional modules. This kind of approach is particularly interesting for exploring the modularity concept in car design. Other methods are based on the interpolation of shapes or `morphing' originating from mental images representing a particular type of object. These systems can be applied to various areas of design to combine two different shapes at a certain level of combination. This last process takes its inspiration from the natural mental process of stylists.

3.3.2

Computer aided styling as fast shape design using a modeller based on sketch input with an object data structure system (developed at the delft university of technology [START_REF] Van Dijk | New Insights in Computer Aided Conceptual Design[END_REF] The Fast Shape Designer enables the simultaneous generation of ideas and sketching by the designer. Initially, designers can either feed in an old model and select curves from a library to create a new model or sketch a new curve with the sketch Manipulator. They must then reposition the curves in a 3-dimensional object space and identify the topology to the curve mesh by linking curves together. The ®nal stage consists of ®lling in the holes in the curve mesh with smooth patches and changing the patches iteratively by sketching or repositioning curves. The system is completely interactive and does not require precise values during sketching. It is closer to the architectural approach (2-dimensional-b3-dimensional) than to the sculptural one, because it is based on curves sketched by hand in a freely positioned plane.

Computer aided styling based on the generation of aleatory forms by aleatory generation softwares (sapporo school of the arts ± japan)

A form is considered to possess emergent factors and each factor its determining and selecting processes. An in®nite combination of factors can be obtained by introducing random decisions in the process [START_REF] Shiroma | A Study on the Generation of Aleatory Forms by Aleatory, ICED 99[END_REF]. In order to generate aleatory texture forms, the following emergent factors have been de®ned: texture generation functions, attributes of basic geometric elements, background colour, painting times, and displacement distances of geometric elements. Designers complement brief data by researching visual information. A Management system of investigation of the relevant information can be of assistance on condition their needs are integrated in terms of researched items, presentation size (format) of data, or research strategies. The study of new software by the Research Centre for the Study and Observation of Living Conditions shows that the informative vagueness at the point of departure emanating from the CDC can constitute a designer creativity domain. But, if the informative contribution of the software is detailed, its appreciation is accompanied by designers having an impression of a `dispossession of the capacity for imagining and sensibility (F F F). Designers have a certain dif®culty to accept an already de®ned environment, and fear being dispossessed of this part of the search for information which is an integral part of their work [START_REF] Balayou | Logiciel De Visu[END_REF]'. Indeed, this tool tends to automate their activity. On the other hand, if the current models produced often lose the formal allegiance of designers to some extent throughout the design process, the use of digital Trends Data base tools can enable the direct extraction of element (textures, formal motives, `morphings') and their direct application to the digital model, the insertion of the model in environments to highlight harmonies, and direct realization of the Formal characteristics of the real model by rapid prototyping.

Perspectives

A general digital tool offering a module of Computer Aided Styling in an environment where it is possible to recall pre-existing elements would allow a reduction in the number of models and consequently preference for the evaluation phases. Such a tool thus combines time reduction and cost reduction.

The appearance of future tools can now be expected with the new Computer Aided Design Tools based on object data structuring. Object data structuring allows the integration of numerous modules into the same software system ± data (static) and procedures (dynamic) that manage them are grouped within the same entity ± the object. The object is de®ned by its behaviour (not by its structure). Every new object has to be functionally explained. Chirowsky gives an example through the realization of CAADIE software: `objects are not enounced in terms of form but in terms of functions and performances [START_REF] Chirowsky | User Interface in Conceptual Generation Design[END_REF]'.

Functionnal modes of object enable the realization of performance analysis and their match with brief constraints (measurement controls, kinematics calculations, etc.). Even if CAD tools are not yet ready to be used in very early design stages, they promise time-saving (shorter CAD/CAM link) with greater ¯exibility (ability to store models and to modify them) and a considerable communication impact (availability on the Internet, reproduction on different scales). On the other hand, not only can they increase representation realism with the possibility of producing very complex shapes and of displaying them in speci®c dynamic environments, but they can also perform representation and evaluation with fast 3-dimensional to 2-dimensional representation generation. With object data structuring they could enable multiple evaluation from the brief in a unique environment effectively meaning evaluation in real time (aerodynamics constraints, safety constraints, package constraints, semantic matching by means of speci®c con®gurations, kinematics analysis, etc.). During sketching, traditional tools are considered superior with respect to rapidity of execution, ®delity to ideas and freedom of creation. CAD tools must provide improved sensorial relations between designers and their physical representation.

Bibliography

Figure 2

 2 Figure 2 Description of a materialization cycle [3].

Figure 1

 1 Figure 1 Evolution of the computerization process in engineering design [1].

Figure 3

 3 Figure 3 Representation of the diachronous design process (adapted from Lebahar) [3] [4].

Figure 4

 4 Figure 4 Description of an informational cycle.

Figure 5

 5 Figure 5 Description of the informational process in design activity.

Figure 6

 6 Figure6Informative needs in design[START_REF] Bouchard | Conduite Inter-organizationnelle et SysteÁ me d'information : Management Re seau par le Syste mier Automobile dans le Cadre d'une Co-conception[END_REF].

Table 1

 1 New digital tools for the Information/Generation/Decision phases in the design process.

	Phase	Activities	Prevailing cogni-	Type of tool	Sources
			tive need
	Information De®nition of the	Investigation	Design watch	Credoc [13] tatung
		problem area		database	company [6]
		Research of
		inspiration
		sources, references
		and in¯uences,
		matching them to
		the brief
	Generation Formalization of	Vizualisation	Computer aided	Tatung company
		external or	2-dimensional/	styling based on	[6]
		internal technical	3-dimensional	morphology,
		solutions or part	sensory	interpolation and
		of solutions	communication	geometric
				transformation
		Modi®cation of		Computer aided	Delft university
		solutions or parts		styling as fast	[20]
		of solutions		shape design using
				a modeller based
				on sketch input
				with an object
				data structure
				Computer aided	Coventry Univer-
				styling based on	sity [14]
				sketches using a
				combination of
				extrusion and
				projection
				techniques
				Computer aided	Sapporo school of
				styling based on	the art [15]
				the generation of
				aleatory forms by
				aleatory
	Decision	Individual evalu-	Deduction	Automatic	CompieÁ gnes
		ation of solutions		semantic analysis	University [16]
		Collective
		evaluation of
		solutions Selection
		Deduction

  3.3.4 Computer aided styling based on sketches using a combination of extrusion and projection techniques (developed at coventry university ± VIDE center)At Coventry University, a large research project in collaboration with car manufacturers (the Digital Mock-up Program) `concentrates on new modelling methods for the car industry, in order to support the design process from conception to manufacturing and avoid the current practice of linking a variety of incomplete and expensive models of components and assemblies for design and evaluation purposes'. The initial stage deals with the integration of Computer Aided Styling in the process enabling early validation and manufacturing phases through the use of a combination of enhanced sketching techniques, novel modelling approaches and rapid prototyping technologies. The new software enables the designer to `produce implied 3-dimensional computer models from 2-dimensional automotive concepts sketches using a combination of extrusion and projection techniques'.

	3.3.3 Computer aided information research in design (project backed by the research
	centre for the study and observation of living conditions in collaboration with
	renault, paris)


Carole Bouchard
email: bouchard@paris.ensam.fr

Dokshin Lim

Améziane Aoussat

Development of a KANSEI ENGINEERING SYSTEM for Industrial design : Identification of input data for KES

Keywords: Industrial Design, Conjoint Trends Analysis, Integration of Knowledge, Kansei Engineering

The main current evolutions in industrial design research are the following :

1 The computerization of the early design phases 2 Consumer and user centered design with in particular emotional design 3 The concurrent engineering, with collaborative work supporting tools Our goal is to modelize the preliminary phases of traditional industrial design process, in order to build new computer aided design tools in accordance with these evolutions, and above all based on the natural thought process of the designers including their own intuitive watch activities.

Many research have been led in Kansei Engineering since the seventies, with many successful results. If we consider that the design process includes the three following phases : information, generation and evaluation, we can consider that most part of the studies in Kansei Engineering are more centered on applications for the generation and evaluation phases. We will focus here on the information phase, related to the input data of the Kansei Engineering process, with the presentation of a method of trends analysis, that we defined on the base of the results of a study of the cognitive activity of the designers.

Introduction

If we consider the whole industrial design process, computers are widely used for the product development to perform the detailed design tasks that meet physical requirements [START_REF] Hsiao | A neural network based approach for product form design[END_REF]. Due to the specificity of the activity of an industrial designer linked with image, feelings, emotions, and sensations, it is to more difficult to develop Computer Aided Design tools for the earliest phases of the design process, especially where the design information inputs are vague or ill defined. But the need to reduce costs and delays while increasing the variety of the offer, leads to a formalization and to a computerization of the earliest phases in a pro-active way.

Kansei Engineering methods aim to handle with peoples emotion analysis to elaborate new Computer Aided Design Tools for emotional design. Indeed, today consumers satisfaction is mainly based on emotional performance of products. The methodology integrates an evaluation phase (evaluation of the image of a designed stimulus) and a generation phase (generation of design candidates with prediction of the consuming behavior).

Our aim is here to modelize the early design activity, to finally propose an information phase (for the implementation of the databases). The resulting model will be based on a phase like iterative process centered on designers natural thought process, with unprecise data and functions of searching, evaluating, and comparing different alternatives. This modelization will provide input data that are usually involved in the industrial design process. Indeed, the study of the cognitive activity of the designers is very rich concerning the variety and freshness of the input data they use in the design process. Consequently the creativity process is implemented, with a great potential of more or less radical innovation. The following contents of the paper will be presented in

Description of the industrial design process and its different phases

The design process can be seen as an information process where the design space problem (the brief) will be gradually transformed into a space solution (the 3D model). More detailed, the design process can be seen as an information production process, i.e. a set of successive cycles (See figure 1) of design materialization with the manipulation of an increasing number of concrete representations of physical objects to reach the Final Solution, with a space problem being set in a space solution for each cycle [START_REF] Bouchard | Modelization of the car design process[END_REF]. Finalized intangible information is transformed step by step into tangible information by way of mental and physical representations. The physical system supplies the external memory modifying the problem of perception in a decisive way. At any time in the process, designers must be able to assimilate and deal with a large volume of information without losing sight of objectives. This equivalence characterizes the problem/solution space. The design process consists in reducing abstraction through the use of various successive levels of representation integrating increasingly numerous constraints. It is characterized by H. Wang as concepualization including an iterative cycle of mental solutions shown with a given problem [START_REF] Wang | An approach to computer-aided styling[END_REF], where (1) the selection of a solution or partial solutions enable the limitation of uncertainty, and keeping in mind the necessary level of vagueness in modifications during subsequent phases [START_REF] Lebahar | Le travail de conception en architecture : contraintes et perspectives apportées par la CAO[END_REF]), (2) new constraints are then added by preserving shape and initial ideas, with (3) the display of a new physical representation generating new ideas and new solutions. P. Lloyd and P.Scott [START_REF] Lloyd | Discovering the design problem[END_REF] describe the design process as generative, deductive and evaluative statements in the activity of design.

We consider the design process can be based on the three following phases [START_REF] Bouchard | Design process perceived as an information process to enhance the introduction of new tools[END_REF] :

Information phase

Designers integrate many categories of information that will be gradually formalized as design solutions throughout the design process. The information and data integrated by the designer can be categorized into information connected to the project (brief or datas sought by the designer to complete it), and the designer's own information stemming from his interactions with the surrounding world. These one include sources of inspiration, references and influences. Sometimes they are dominating over the information connected to the problem. This is both an open and closed phase.

Generation phase

This phase consists in the generation of new ideas and new solutions : by means of numerous mental images and from brief data and other information contained in any design project, designers can generate physical representations and physical solutions as 2D and 3D models.

This requires the use of manual or digital tools, depending mainly on designer skills and on corporate culture. This phase can be performed in accordance with various "applied creativity" methods and tools, which enable the generation of a large volume of ideas, possibly even including the points of view of other non-designer players (ergonomists, sociologists etc.). The generation phase is an open phase.

3 Evaluation and decision phase

The choice of the right design solutions to be developed physically is achieved by an evaluation and deduction process. It uses criteria from the initial or reviewed brief to help choose the best solutions. The Evaluation and Deduction phases are analytical phases. Many methodological tools can back up these phases such as functional analysis and semantic evaluation. This phase is a closed phase.

Designers and non-designers do not posses the same differentiation capability (G. J. F. Smets, C. J. Overbeeke, 1995 [START_REF] Smets | Expressing tastes in packages[END_REF]). Semantic differentiation by Factorial Analysis is another evaluation/prediction model determined by a visual evaluation of the image of products.

Application of semantics helps designers to understand and evaluate their own communication models. Communication is successful by matching the response to the signal.

All information cycles (see figure 2) contain an informative phase, a generative phase and a decision-making phase (evaluation-selection) whose outcome is an intermediate representation that will be used for the transmission of project information to the other players and -compared with the previous cycle -as a more concrete informative mass. The efficacy of each phase will influence the whole process and the three phases should be of equal value to achieve optimal results. If one of them fails, the general process and of course the final result will fail. Currently, software is being assessed to assist designers in the digital realization of the phases of generation and of evaluation.

Problematic

In this part, we will explore many sources in Kansei Engineering before to express the problematic.

Definitions of Kansei Engineering

Most of the available methodology for consumer oriented design born in Europe to introduce consumers in the design process focus on functional and quality rather than emotional performance of products. On the other hand, the analysis of users perception have been traditionally studied using market research techniques in which users participate only as an evaluation source (and not as requirements generator), and products are evaluated and then redesigned if deemed necessary. This strategy is above all based on trial and error methodology that shows serious drawbacks.

In this sense, Kansei Engineering , sometimes referred to as "emotional design" or "sensory engineering", aims to translate consumers psychological feeling about a product into perceptual design elements, allowing design and evaluation of products before launching them on the market. This technique, which was developed in Japan in the seventies, involves determining which sensory attributes elicit particular subjective responses from people, and then designing a product using the attributes which elicit the desired responses. In order to perform Kansei engineering, many studies have been led through a semantic approach (Jindo & Al, 1995 [8], 1997 [START_REF] Jindo | Application studies to car interior of Kansei engineering[END_REF], Ishihara & al, 1995 [10], 1997 [START_REF] Ishihara | An analysis of Kansei structure on shoes using self-organizing neural networks[END_REF], Tanoue & al, 1997 [START_REF] Tanoue | Kansei Engineering : A study on perception of vehicle interior image[END_REF], Yang & al, 1999 [START_REF] Yang | Rule-based inference model for the Kansei Engineering System[END_REF], Hsu, 2000 [START_REF] Hsu | A semantic differential study of designers and users product form perception[END_REF], Chuang & al, 2001 [15], Hsiao, 2001 [START_REF] Hsiao | A neural network based approach for product form design[END_REF]), where subjective responses using sets of bipolar attribute rating scales are produced, for the assessment of a set of products sufficiently diverse to provoke a wide range of different emotional responses. The ratings are then statistically compared to provide a distribution of products across the different rating criteria. Analyzing all products rated highly on a particular characteristic allows you to draw conclusions about which perceptual elements are responsible for eliciting this subjective judgment.

More recent approach have been done, based on the recording of action in real time when people are appreciating fine-art work for example (Suh [START_REF] Suh | Sensory (Kansei) Engineering of Aesthetics in Textile Fabrics, Code Number: F99-S2[END_REF], 2000, Lee [START_REF] Lee | Modeling structure of Kansei : An analysis of how people appreciate art through a remote controlled robot[END_REF], Harada, 2002 [18]). According to the authors, the langage is not a sufficient modality to describe Kansei. Eyes motions and brain-wawes have to be recorded and mesured as well. Anyhow, this method is not incompatible with other traditionnal Kansei methodologies. It complements those and they could be easily integrated in a single Kansei System. Finally, certain methods focus more on the evolutionary techniques and more particularly on the genetic operations allowing to generate a wide range of design solutions (Sato, 2001 [19] ).

Problematic

The majority of studies in Kansei Engineering are centered on applications for the Generation and Evaluation phases, whatever the direction will be between forward Kansei Engineering or backward Kansei Engineering (Nagamashi, 2002 [20] ).

In the forward approach, the contents of the data bases gathered in the information phase are essentially the words coming from previous consumers evaluations or the commercial litterature, and design elements coming from different sources from the designers. In the backward approach, the evaluation results are the essential source of information.

The information process in the traditional design activity is a crucial part of the design process. The novelty of the design candidates depends mainly of this part, and of the manner to integrate this information during the generation phase too. A specific study showed that creative thinkers usually use more environmental datas (datas not directly linked to the problem to solve) (Ansburg & al, 2002 [21] ). Designers could be helped in this phase of information gathering, because they have to manage and categorize a huge number of datas. In that sense, some researchers worked on a new image retrieval system which uses specific object names in addition to impression words which can reflect ambigous human kansei as retrieval keywords (Kuroda, 2002 [22] ).

Early Models Initial brief

Information

Generation Evaluation Decision

Fig.3 Description of materialization cycle in Kansei Engineering [3]

Forward Backward

As a matter of fact, sources of inspiration, references, and influences play an important role in the design process, both in defining the context for new designs and in informing the creation of individual designs. Previous designs and other sources of ideas furnish a vocabulary both for thinking about nex designs and for describing designs to others (Eckert, 2000 [23] ). Designers use a large variety of types of sources coming from different areas as comparable designs, other types of design, images of art, beings, objects and phenomena from nature and everydaylife. Sources of inspiration are an essential base in design thinking, as definition of context, triggers for idea generation, and anchors for structuring designers mental representations of designs. Our purpose here is to study the cognitive activity of the designers especially during the information phase, in order to extract a model of the cognitive process aiming to develop a specific conjoint Trends Analysis Method. This method will support for the elaboration of new digital tools.

4. Experiment : a study of the cognitive activity of the designers related to the information phase

1 The questionnaire setting

The study [START_REF] Bouchard | Modelization of the car design process[END_REF] included two complementary separate phases : the questionnaire and the protocol study. The extraction of datas concerning the information phase of the design process was maily based on the questionnaires.

The questionnaires were centered on the identification of the information and data integrated in the design process by car designers. We sought after 40 professional designers of European car motor companies and students in transport design. Results related to their own design process including a focus on their their sources of inspiration, references, influences and conscious mental images, and were completed with the results of the protocol study.

The contents of the answers of the referees were categorized by a contents analysis including the number of occurrences for each category.

2 Results related to information and data integrated in the design process

After consideration of the information contained in the brief, an information search process is systematically performed by the designers to fill in the problem space with non dimensioned values. Strong visual elements are extracted from various sources of inspiration, references and influences, linked with their personality and intuition. The datas integrated in the conceptualization come from different fields, more or less directly linked with the initial domain. The following areas were mentioned : Information details derive from a deliberate information search effort carried out in order to meet the specifications of the brief and from the more or less conscious re-activation of knowledge previously memorized during various activities possibly going beyond the professional context. The result of the information research is translated preferably by the visual shape (trend panels, various sketches, etc.), the textual mode being used to highlight the key points. The designers carry out a more or less systematic and organized investigation, from a simple glance through to the making up of trend panels and databases connected with the initial domain or other domains of influence. This is performed in part by visits to showrooms and exhibitions and by image integration.

The investigation process carried out by subjects in areas other than car design remains highly subjective and personal. These areas include various domains, activities, centers of interest or leisure activities to which the designer refers to on an irregular basis and for which frequency and performance are relatively variable.

Showrooms or exhibitions visited and regular readings involve transport, with a major representation of this initial domain, architecture and many other fields that are not necessary shared (See Table 1).

Presentation of the Conjoint Trends Analysis (CTA) method

The results of the cognitive activity of the designers related to the earliest phases of design allowed the modelization of the method of Conjoint Trends Analysis [START_REF] Bouchard | Identification and integration of product design trends[END_REF]. This approach enables the identification of formal attributes linked to particular environments in order to use them in the early design of new products. More precisely, it involves the formalization of sociological, chromatic, textural, formal, ergonomic and technological trends.

Procedure for drawing-up trend boards

The originality of the approach lies in the identification of sociological end values and in the use of various domains of influence (See Figure 4, first step, and Figure 5 on the left), in order to enrich the design solution space. The first analysis tool is the iconic content analysis. The iconic content analysis allows to highlight and build the coherent representation of a perceptual field (ambience), and understand its structuralization (Step 2).

This process implements phases involving observation, gathering of information, composition and verbal designation. Then the palettes will be extracted and ordered in harmonies in order to conceive a product's shape, colour, usage and texture components in conjunction the initial perceptual field (Step3). The trend board offers an relatively exhaustive representation of the references usually used by the designers for their composition. It reinforce the link and semiotic coherence between the end values of the consumers, functionalities in any domains of influence, and products attributes as form, colour, texture, and usability principles. The links between semantic choices in a specific context and their formal significants are formalized under the form of a single representation : the trend board. The visualisation of the board enables the observer to become impregnated with a formal impressionist synthesis also called harmony, atmosphere, ambience, context and environment.

Determination of fields of influence

• Gathering of illustrations on the studied products • Evaluation and data analysis • Mapping and identification of fields of influence • Specification sheet

Identification and formalisation of trends

• Gathering of illustrations on the products of fields of influenc

• Analysis of iconic content and categorization • Cognitive chaining and drawing-up of trend boards and palettes

Integration of shapes, uses,colours, textures and technologies in the design project

• Matrix of coherence • Creativity • Concepts generation Contexts are decisive in the attribution of a signification to the object. The fact that the concept is in harmony with its context adds not only to its merely semantic contribution but also to its aesthetic contribution. The context generates an atmosphere by the juxtaposition of different levels (tangible, formal, symbolic, etc.) while taking into account the dynamic relations between these features.

The trend boards thus obtained, as a whole, are representative of trends in the field of investigation. Trend boards The follow-up approach is therefore important. Information originating from the achieved follow-up process is centralised, capitalized and redistributed using current Information Technology media ( Web, CDROM, Database management systems, etc.).

Integration of the trends in the design process

Trend analysis corresponds to the information phase (See page 3). It plays an important role in defining and validating the requirement and contributes in translating it into the form of a specification sheet. The trend follow-up which is set into play with creativity sessions sorts information into boards and shade cards which can be digitised and regularly updated within the framework of a follow-up process. The results of trend studies are used either directly by the project team to conceive product attributes, or used as arguments in favour of pre-conceived solutions. It is also a communications tool used within the project team or between the latter and the management team or even for external communication (distribution in press kits, sales brochures, trade fairs, etc.). Fig. 6 An example of integration of trends in design : "AQUABIO" trend

Conclusions

After a presentation of the design process under the form of a succession of information-generation-evaluation cycles, we emphasized the fact that the information process play a major role especially in providing a certain originality in the generated design solutions. Besides, designers, according to the traditional design process, integrate some particular trends linked to the world of the consumer, and that the consumer himself is not able to identify.

Our purpose here was to explore the potential of the integration of the method of Conjoint Trends Analysis in Kansei Engineering, helping to define and formalize input data corresponding to the information phase of the design process.

To our mind, this method based on a deep analysis of the cognitive processes of the designers, will lead further studies in order to implement the actual Kansei Systems with specific mathematic tools as neural networks.

Fig. 1

 1 Fig.1 Description of a materialization cycle

Fig. 2

 2 Fig.2 Description of the information process in design activity

Fig. 4

 4 Fig.4 The conjoint Trends Analysis

Fig. 5

 5 Fig.5 An example of trend panels and palettes : "AQUABIO" trend

Table 1 :

 1 Sources of inspiration, references, and influences used by car designers during the firt generation of ideas , semiotics, ergonomics, sensory characteristics, taste). It is true that, to a greater or lesser extent, designers project their own expression through the object. This phenomenon gives partially the originality of a concept, with references that are more or less linked with socially recognized styles. Certain concepts are thus endowed with a signature by which the producer of the Shape can be recognized.

	Universe of Arts	Universe of nature (biomorphism)	Universe of objects and products
	Painting	Vegetables	Architecture
	Drawing	Plants	Furnitures
	Cartoons	Flowers	Fashion design
	Graphic arts	Minerals	Aeronautics
	Cinema (Science-fiction)	Stone	Hi / fi,
	Sculpture	Animals	Video
	Music	Insects	Telecommunications
	...	Felines	...
		…
	Particular items are sought out across these domains such as (1) impressions connected with global perception
	(creativity, modernity, innovation, impressions, sensations, spirit, trends), (2) stylistic elements (aesthetics,
	proportion, structure, shape, line, volume, relief, colour, motifs, textures), (3) technical characteristics
	(aerodynamics, engineering performance, technologies, materials, internal details) and (4) consumer-related items
	(adhesion values

Table 2 :

 2 Percentage of visited Show rooms, exhibitions and of regular readings of the car designers

	Visits of Show-roms and Exhibitions	Transport	72%
		Architecture	10%
		Plastics	8%
		Objects	6%
		Painting	4%
		Information technologies	4%
		Furniture	1%
	Regular readings	Transport	58%
		Architecture	10%
		Consumer information	8%
		Design	5%
		Fashion	3%
		Popular science	3%
		Graphic design	3%