A Model- based Expert System Shell

Rule-based expert systems, despite having demonstrated their usefulness in many circumstances, have been widely attacked for the shallowness of their knowledge. They have no knowledge about the knowledge which they possess and therefore can only be used in a very rigid manner. This paper shows that this meta-knowledge can be extracted from the rule base of an expert system and by producing a model of the artifact(s) described within, extend the functionality of the overall system. One of the benefits of this extended functionality is the ability of the model-based expert system to interface with external systems such as existing CAD systems. This paper describes the development of a general model-based expert system developed in the Department of Architectural Science, University of Sydney. The utility of the approach is shown in an example of the system interfacing with a commercially available CAD system. The CAD system is used to define the features of a building and a rule base dealing with some aspects of building regulations is applied to interpret the database produced by the CAD syste