||The present paper describes on-going research on Collaborative Design.
The proposed model, the resulting system and its implementation refer mainly to architectural and building design in the modes and forms in which it is carried on in advanced design firms.
The model may actually be used effectively also in other environments. The research simultaneously pursues an integrated model of the:
a) structure of the networked architectural design process (operators, activities, phases and resources);
b) required knowledge (distributed and functional to the operators and the process phases).
The article focuses on the first aspect of the model: the relationship that exists among the various ‘actors’ in the design process (according to the STEP-ISO definition, Wix, 1997) during the various stages of its development (McKinney and Fischer, 1998).
In Collaborative Design support systems this aspect touches on a number of different problems: database structure, homogeneity of the knowledge bases, the creation of knowledge bases (Galle, 1995), the representation of the IT datum (Carrara et al., 1994; Pohl and Myers, 1994; Papamichael et al., 1996; Rosenmann and Gero, 1996; Eastman et al., 1997; Eastman, 1998; Kim, et al., 1997; Kavakli, 2001).
Decision-making support and the relationship between ‘private’ design space (involving the decisions of the individual design team) and the ‘shared’ design space (involving the decisions of all the design teams, Zang and Norman, 1994) are the specific topic of the present article.
Decisions taken in the ‘private design space’ of the design team or ‘actor’ are closely related to the type of support that can be provided by a Collaborative Design system: automatic checks performed by activating procedures and methods, reporting of 'local' conflicts, methods and knowledge for the resolution of ‘local’ conflicts, creation of new IT objects/ building components, who the objects must refer to (the ‘owner’), 'situated' aspects (Gero and Reffat, 2001) of the IT objects/building components.
Decisions taken in the ‘shared design space’ involve aspects that are typical of networked design and that are partially present in the ‘private’ design space. Cross-checking, reporting of ‘global’ conflicts to all those concerned, even those who are unaware they are concerned, methods for their resolution, the modification of data structure and interface according to the actors interacting with it and the design phase, the definition of a 'dominus' for every IT object (i.e. the decision-maker, according to the design phase and the creation of the object).
All this is made possible both by the model for representing the building (Carrara and Fioravanti, 2001), and by the type of IT representation of the individual building components, using the methods and techniques of Knowledge Engineering through a structured set of Knowledge Bases, Inference Engines and Databases.
The aim is to develop suitable tools for supporting integrated Process/Product design activity by means of a effective and innovative representation of building entities (technical components, constraints, methods) in order to manage and resolve conflicts generated during the design activity.