Property-Oriented Information Systems for Design Prototypes for the BAS•CAAD System Sverker Fridqvist Division of Architectural and Building Design Methods Department of Construction and Architecture Lund Institute of Technology Lund University PROPERTY -ORIENTED INFORMATION SYSTEMS FOR DESIGN Prototypes for the BAS•CAAD System Thesis for the degree of Doctor of Technology to be presented with due permission for public examination and criticism at the School of Architecture, Lund Institute of Technology, on the 28th of September 2000, 10.30 am. Respondent: Sverker Fridqvist Opponent: Per Galle Examination Comittee: Robert Bjärnemo Greger Dahlström Hans Lindgren Väino Tarandi Lars-Henrik Ståhl Supervisor: Anders Ekholm © 2000 by Sverker Fridqvist Printed by KFS i Lund AB ISBN 91-7874-062-2 LUND INSTITUTE OF TECHNOLOGY Department of Construction and Architecture Division of Architectural and Building Design Methods P.O. Box 118 • 221 00 Lund • Sweden http://www.caad.lth.se ABSTRACT This thesis reports the author’s work within the BAS•CAAD project, and is part of the total report on the project. Property-oriented systems are a new kind of information systems that are based on concepts of properties instead of concepts of things or classes of things. By focusing on properties, the property-oriented sys- tems become more flexible and more suited to the dynamic early stages of design than the traditional class-oriented systems can be. The theoretical framework for property-oriented systems developed within the BAS•CAAD project and presented in this thesis has previ- ously been presented in several papers, a selection of which are included here. Some of the basic considerations from the papers are further de- veloped in a separate chapter. Additionally, the thesis covers several questions regarding prerequisites for and implications of property-oriented systems. These questions have not been addressed in earlier BAS•CAAD publications. The development of research proptotypes based on the theoretical framework is presented, with a discussion of the different versions and the considerations behind them. A study of the history of computer aided building design has revealed that many basic ideas of today were developed the first time at the be- ginning of electronic computing, in the early sixties. Since the early de- velopment seems to be unknown today, a brief account is presented in this thesis, with special focus on issues considered in the BAS•CAAD project. Finally, the experimental architectural design software DASK, devel- oped mainly by the present author in the later 1980s, will get its first presentation in writing in this thesis. SAMMANFATTNING Denna avhandling rapporterar författarens arbete inom BAS•CAAD-pro- jektet, och utgör en del av den totala rapporteringen av detta projekt. Egenskapsorienterade system (eng: property-oriented) är en ny slags in- formationssystem som är baserade på begrepp för egenskaper istället för begrepp för ting eller klasser av ting. Genom att fokusera på egenskaper, kan de egenskapsorinterade systemen göras mer flexibla och mer lämpade för de tidiga skedena av design än de traditionella klassori- enterade systemen kan vara. Det teoretiska ramverk för egenskapsorienterade system som uvecklats inom BAS•CAAD-projektet och som presenteras i denna avhandling, har tidigare presenterats i ett flertal uppsatser av vilka ett urval finns ink- luderade i denna avhandling. Några av de grundläggande tankegångar- na från uppsatserna utvecklas vidare i ett särskilt kapitel. Dessutom avhandlas ett antal frågeställningar som berör förutsättningar för och följder av egenskapsorienterade system. Dessa frågeställningar har inte berörts i tidigare publikationer från BAS•CAAD-projektet. Utvecklingen av programprototyper baserade på det teoretiska ramver- ket presenteras tillsammans med en diskussion över de olika versionerna och bevekelsegrunderna för dem. Ett historiskt studium av datorstödd byggnadsutformning visar att många grundläggande ideer som används idag togs fram för första gån- gen redan under datorns barndom, under det tidiga 1960-talet. Efter- som den tidiga utvecklingen förefaller okänd idag, presenteras en kort redogörelse i denna avhandling, med speciell inriktning på problem som behandlats i BAS•CAAD-projektet. Slutligen presenteras i denna avhandling för första gången i skrift det för arkitekter avsedda designprogrammet DASK, som utvecklades un- der senare delen av 1980-talet, huvudsakligen av författaren. PREFACE This thesis reports my work within the BAS•CAAD research project at the division of Architectural and Building Design Methods at Lund In- stitute of Technology. BAS•CAAD is an acronym for Building and user Activity Systems modelling for Computer Aided Architectural Design. The name reveals the original focus of the research, which was to pro- vide a design system for modelling buildings and user activities as ob- jects, simultaneously. In this book, I have collected what I have learnt during approximately 14 years of developing and studying software for architectural design. It seems that computer systems for architectural design have yet to be pro- duced. I have tried to show some reasons why this is so, in spite of sev- eral decades of research and development in this area. However, the main focus of this thesis is the BAS•CAAD project, and what we have learnt and achieved during the years of this research project. I went trough my architectural education in Lund in the early 1980s. I had become dissatisfied with the traditional architectural sketching on tracing paper, which seemed unnecessarily cumbersome in the new era of computing. Having had experiences with word-processing on com- puters (WordStar!), I believed that computer aided design might be as liberating to the designer as word processing was to the writer. Towards the end of my education, I had made an agreement with a Swedish ven- dor for Medusa Bygg, a commercial CAD application for the Swedish AEC sector. They would finance my computing expenses at the Lund University Computer Centre, and provide me with an introductory ed- ucation in using the system. Jonas af Klercker was willing to be super- visor for the work. iii My intention was to investigate if Medusa would be useful as an archi- tectural sketching tool. Alas, to my disappointment, it was not. The software was too complicated in itself, and the user interface, with an alpha-numeric terminal, a storage-tube display, a joy-stick for manipu- lating the cursor on the storage-tube, and a digitizer with an overlay for command input was quite demanding. When I had completed my exam work I was engaged by Jonas af Kler- cker (see below) to develop a new, improved version of his architectural design software, called DASK [see p. 187]. The DASK software, imple- mented on a PC under DOS, handled architectural items such as walls, doors, and windows. This was an improvement over the so-called CAD (Computer Aided Design) software then available, which handled only graphical items, such as lines and curves. The idea was that the architect should not need to bother about lines, when the computer could be programmed to do that for him. The development of DASK was eventually overrun by commercial soft- ware; notably ArchiCAD, and DASK was put to rest. A new project, BAS•CAAD, was started by Anders Ekholm (see below), to research and define a theoretical basis for architectural design systems. I was en- gaged to implement the theoretical conceptions in computer programs, as a means to investigate the ideas practically, as well as the ideas’ prac- ticality. Acknowledgements Two persons have been of especially great importance for me to become involved in computer aided architectural design, and for being able to present this thesis; thus it seems appropriate to present them here: Anders Ekholm, Dr, associate professor, is an architect with more than 25 years’ experience of practice and research. His thesis The System Man – Building, an ontological perspective (title translated from Swedish), presented in 1987, is an application of generic property theory and sys- tems theory to a description of the built environment from the archi- tect’s perspective. Ekholm initiated and lead the BAS•CAAD research project sice its start in 1994. Since then he has also been engaged in in- ternational building classification work. He has been my supervisor for this thesis, and my main source of knowledge about systems theory and building classification. iv Jonas af Klercker, tech. Lic, associate professor, is an architect and a teacher at the School of Architecture at Lund Institute of Technology. He has been the driving force in establishing computer education at the School of Architecture, and he is also active in the ECAADE (Educa- tion in Computer Aided Architectural Design in Europe) organisation of CAAD educators. Jonas af Klercker started the Computer Studio at the School of Architecture in Lund in 1987 and engaged the author to write the DASK software and to be a teacher in the computer courses. Without Jonas af Klercker’s initiative to establish the Computer Studio, I would plausibly not have been engaged in this research. The research presented in this thesis has been financed by grants from the Swedish organisations NUTEK and BFR, the Swedish National Board for Industrial and technical Development, and the Swedish Council for Building Research, respectively. I am grateful to the department’s adminstrative head Bengt Hansson for allowing me the time needed to finish the thesis. I would also like to mention my colleagues at the department, Stefan Engdahl and Faisal Shukur, with whom I have spent a few pauses dis- cussing subjects that not always were closely connected to work. I have gained much from discussions and talks with fellow researchers around the world on conferences and workshops. Also the knowledge that other people take interest in similar questions as I do has been en- couraging. Finally, I would like to thank my Mother, who gave me my life, my brother Kristian, and my sister Ann and her family, whose home always has been open for me.