Knowledge Transformation in Conceptual Design: An Approach to Build a Model of CAID Knowledge System

 

TAN Hao, PhD Candidate

School of Design, Hunan University, Changsha, China.

e-mail: htan@hunu.edu.cn

 

Prof. ZHAO Jianghong

School of Design, Hunan University, Changsha, China.

e-mail:zhaoma@public.cs.hn.cn

 

 

Abstract

Conceptual design is a process of transformation from the interpreted initial state into the requirement-matching goal state, in which knowledge transformation plays a key role. From a perspective of design, a model of knowledge transformation is built, and there are two stages in knowledge transform, one is knowledge analysis charactered by discovering and finding in realm of theory, and the other is knowledge synthesis charactered by inventing and making in realm of practice. Then, knowledge and their transformation in conceptual design are discussed in the paper in terms of four cognitive levels: physical, perceptual, functional and conceptual. And a protocol experiment was adopted to demonstrate the model of knowledge transformation. Based on the model of knowledge transformation, the paper presents a conceptual model of a CAID knowledge system, which offers design aids for designers throughout two stages, and may generate new forms and designs if with AI technologies, like Generative Design.

Key Words: Knowledge Transformation, Conceptual Design, Cognition, Knowledge

1. Knowledge and Design

Design is a kind of business in which skills and expertise are acquired after learning basic techniques, assimilating domain specific and general knowledge, and absorbing past good cases. The acquired expertise, however, is often tacit and implicit. Even experienced designers cannot be clear what kind of expertise they use in designing and how. [1] This is one of the problems in design researches.

In order to solve the problem, Gero, Kavakli, Teeravarunyou, Sato have introduced the concept of information and knowledge into design research and made some progress. [2-4] Knowledge is a type of integrative and meaning-independent information which can be learned, applied and be fed back and be used to forecast things. [5] The essential characteristic of knowledge is that knowledge can be put into practice. Knowledge plays a key role in conceptual design, such as aesthetic knowledge, functional knowledge, user knowledge, sponsor knowledge, etc. [6] In some case, conceptual design is one stage of knowledge transformation process that designers transform their aesthetic knowledge, functional knowledge, user knowledge etc. to products, and products express knowledge to users. (Fig.1)

Design process becomes a process of knowledge transformation.

Fig.1 Knowledge transformation from designers to users

 
 


2. Two Stages of Knowledge Transformation in Conceptual Design

Fig.2 Knowledge using and building

 
Conceptual design is a process of transformation from the interpreted initial state into the requirement-matching goal state. In conceptual design process, knowledge transformation is mainly during the designersí works. Knowledge is used to create objects, and objects are evaluated to build knowledge [7]. Knowledge using and knowledge building are two ways of knowledge transformation in conceptual design. (Fig.2) By the transformation, knowledge changes from inner state into outer state, and products changes from original state into goal state.


From designersí perspective, conceptual design involves two stages: one is knowledge analysis charactered by discovering and finding in realm of theory, and the other is knowledge synthesis charactered by inventing and making in realm of practice. In the two stages,

Fig.3 Knowledge transformation cycle

 
knowledge using and knowledge building respectively do their works. (Fig.3)

 


In the realm of theory, designers use design knowledge and explore the design methods, models and cases by design research in order to acquire the design knowledge and gain the design model and case. Then designers test or demonstrate the model and case to build their design knowledge.

In the realm of practice, designers use design knowledge and design products by their design skills and experiences in order to express the design knowledge and gain products. Then designers research users and markets to build their new design knowledge.

In Fig. 3, there are two knowledge transformation cycles, which are ideas acquisition in realm of theory and ideas expression in realm of practice. In each knowledge transformation cycle, there includes knowledge using and knowledge building. For instance, in realm of practice, knowledge using is a process of designing a new product. Obviously, knowledge is the bridge linking the realm of theory and practice, the process of finding and the making. Knowledge plays a key role in conceptual design.

3. An Experiment

In order to gain a detailed view of the knowledge transformation, a protocol analysis experiment is put forward. From human information process, designersí mental process can be divided into four cognitive levels: physical, perceptual, functional and conceptual. [7] By analysis the protocol reports in the four levels, a knowledge transformation model can be introduced.

Fig.4 One part of cognition action code analysis of protocol reports

 

Five designers were invited to take part in the experiment and heir task is to design one kind of NC machine tools. All the design process is recorded by video. By protocol analysis, we divide the entire protocols into small segmentation. For each segment, we code cognitive actions of designers into the four categories. [1] (Fig.4)

 


Fig.4 is one part of the whole protocol reports and it shows the process of mental analysis of designing the scales of the machines. As it is shown in Fig.4, knowledge building and knowledge using appear in design process and knowledge is the main elements of design. On the other hand, the levels of information processing have an inherent dependency on each other; and a design action on upper level should be inherently dependent on that in lower level. If designers are not satisfied with the works (after designers evaluation, itís in conceptual level), they begin a new process of knowledge transformation.

4. A Model of a CAID Knowledge System

Based on the model of knowledge transformation, we build a conceptual model of a CAID knowledge system. (Fig.5)

In the conceptual model, CAID knowledge system can be divided into two parts: knowledge building parts which applies knowledge aids and knowledge using part which applies design aids. Each part has 4 knowledge transformation levels, which are physical, perceptual, functional and conceptual. The four levels perceptively help designersí designing in design process. On the other hand, theory knowledge and practice knowledge are also presented in the stages of design.

By the model of CAID knowledge system, knowledge can be transformed in design process. Furthermore, in some case, the CAID knowledge system may generate new forms and designs if with Gene Code, Case-based reasoning etc. AI technologies, like Generative Design.

Fig.5 Conceptual model of a CAID knowledge system

 

 


References

[1] Masaki Suwa, Terry Purcell, John Gero. Macroscopic analysis of design processes based on a scheme for coding designersí cognitive actions. The Great Brain: Design Studies (19), 1998

[2] Manolya Kavakli, John S. Gero. The structure of concurrent cognitive actions: a case study on novice and expert designers. The Great Brain: Design Studies (23), 2002

[3] John S. Gero. An approach to the analysis of design protocols. The Great Brain: Design Studies (19), 1998

[4] S Teeravarunyou,K Sato. Object-Mediated User Knowledge Elicitation Method. In: proceeding of the 5th Asian International Design Research Conference. Korea,2001

[5] Devlin,Keith. Infosense. Turning Information into Knowledge. New York: W.H. Freeman and Company, 1999

[6] Jose Carlos Teixeira. Applying Design Knowledge to Create Innovative Business Opportunities. Ph.D. Essays in Illinois Institute of Technology, 1999

[7] Charles L. Owen. Design research: building the knowledge base. The Great Brain: Design Studies (19), 1998

[8] Suwa, M and Tversky, B. How do architects interact with their design sketches in exploring design ideas. Proceedings of 4th Australasian Cognitive Science Conference 1997 Newcastle, Australia (1997) in press