OPS5 in Architecture: Four Test Cases

Abstract

The advantage of production systems such as OPS5 over structured programming becomes most evident when they are applied to large, ill-structured problems. These applications are abundant in architectural design. Although efficient algorithms exist for some domains in architecture, empirical knowledge is essential in others. This situation calls for hybrid implementations with traditional efficient procedural packages providing support for production system front ends. OPS5 is a general-purpose production system language. In each one of-the four test cases, one particular aspect of OPS5 was explored in-depth.

The first test case is an attempt to capture the rules of thumb, algorithms and decision tables contained in the “Small Office Design Handbook” and to turn it into an interactive computerized design consultant.

The second test case is an attempt to build an intelligent knowledge acquisition tool to extract design knowledge from designers with no or very little programming knowledge, and to transform that knowledge directly into OPS5. The expert system has a problem decomposition module and an expert system building component.

The third test program is a knowledge based ROOF DESIGNER, it addresses a subset of the factors and heuristics that designers use to decide on the shape of roofs. These factors and heuristics were determined with a protocol analysis and then transformed into OPS5 rules.

The last test case uses TOPSI, the IBM AT implementation of OPS5, and DRAW, a GKS based graphics program with three dimensional extensions. DRAW acts as a high quality graphics output device of programs written in TOPSI. A user interface allows the construction of new TOPSI rules from graphic input in DRAW.