Developing criteria for PC-CADD evaluations : a case study

Abstract

While the usefulness of CADD in the production stages of the architectural design process is now widely acknowledged, its true benefits for earlier, schematic design phases remain unclear. Due to the very subjective nature of that process and the complexity of its overlap with other design stages, schematic design is a difficult task to model and emulate, therefore making the appraisal of CADD as a design aid a delicate problem. The last few years have witnessed a large increase of PC based CADD systems, most of which aspire to qualify as "true design tools"; however, outside of product release announcements and industry comparative checklists in the professional press, there is little work on the assessment of the role of CADD systems in preliminary design. This thesis is an attempt to develop a strategy for the evaluation of CADD systems as a tool for design in its early conceptual stages. A specific system is selected and assimilated to a level of proficiency. Its main characteristics are then discussed and compared to the similar characteristics of another "standard" generic system, which is the most currently used system. They are analyzed in terms of their relevancy as effective design aids, based on my own observations of the system; they are also tested through a short design exercise. The purpose of the study is to identify what constitutes valid parameters for the assessment of a system performance. Its main functions are prioritized and investigated as to whether they truly assist the user in his design process, with a particular emphasis on geometric modelling, visualization and system interface. A set of performance criteria is derived along with their desirable attributes, so as to develop a comprehensive approach towards CADD evaluation.