The aim of this study is to explore the possible reflections of the design domains on the students’ design behavior by analyzing the similarities and differences between the computer-aided and conventional architectural design process.
A hybrid theoretical model is used to combine two major approaches to design research (rational problem solving by Simon and reflection-in-action by Schön) for investigating the design process.
The focus of this study is on certain topics of design activities, strategies, decisions and their organization in these two different cases. The sub-categories of these topics are inferred from the key findings of previously conducted studies and analysis of pilot experiments.
A comprehensive literature review was conducted before starting to design the research method. Theoretical concepts and empirical findings were revised with the focus on possible dimensions of measurement, analysis and evaluation methodologies. It is found that, although there is a variety of unstructured observations and assumptions about computer-aided design process, only a limited number of empirical studies have been carried out in the related research area. In all of the empirical studies, CAAD process was evaluated in comparison to the conventional design process (these are extensively reviewed in the Section 4.1).
Thus, different descriptions of the design activity by different researchers were reviewed and considered in all research phases, especially while determining the preliminary and final dimensions of measurement.
After a general survey of former empirical research on CAAD, it was decided to conduct a controlled experiment with two conditions: first experimental condition (C01), the subjects were obliged to design with the software they prefer while participants in the control condition (C02) were only allowed to utilize only conventional tools.
The sample population was determined as 16 senior students of ITU Faculty of Architecture. This decision was based on the homogeneity of design expertise and software use among the students, shared design terminology between the researcher and the students, high accessibility of subjects and the possibility of contributing to the architectural design approaches in ITU.
The duration of the experiment was defined as 120 minutes, due to the feasibility issues and time length of previous studies.
The experiments were conducted in ITU Faculty of Architecture and a total of 1890 minutes of protocol recordings were obtained. In terms of the number of participants and length of the experiments, this research is one of the most comprehensive studies ever undertaken among the indexed publications.
The design problem for the experiment was formulated considering the characteristics of the research question, sample population, the duration of the experiment and the problems that were used in similar surveys. The problem description is decided to be relatively short in order to motivate the participants to restructure and redefine requirements.
Analysis of the experiments revealed that there is significant difference between the means of decisions on representation, decisions on the design process, concepts, structure and textual representations in conventional design and CAAD conditions.
Moreover, the overall decisions of the subjects that designed using CAAD software were organized differently throughout time. All of the subjects in this condition took numerous decisions about the design process but very few conceptual ones. They were focused more on creating detailed representations of the existing context. On the other hand, subjects in the conventional design condition used simpler representations and their conceptual decision making process was more continuous.
Co-supervised by Prof. Omer Akin, Carnegie Mellon University
Table of Contents:
TABLE OF CONTENTS vii
LIST OF TABLES x
LIST OF FIGURES xii
1. INTRODUCTION 1
1.1 Motivation 1
1.2 Aims, Scope and Limitations 2
1.3 Methodology 3
2. RESEARCH ON ARCHITECTURAL DESIGN 7
2.1 Scientific Methods of Inquiry 7
2.2 Models and Assumptions on the Architectural Design Process 9
2.2.1 Assumptions on computer aided architectural design 17
2.3 Major Paradigms in Design Research 21
2.3.1 Design as “ill structured” problem solving 21
2.3.2 Design as “reflection in action” 24
2.3.3 Hybrid models of design research 25
2.4 Critical Concepts in Design Research 27
2.4.1 Memory 27
2.4.2 Design knowledge and expertise 30
2.4.3 Representation 31
2.4.4 Visual thinking 32
2.4.5 Design strategies 33
2.5 Analyzing the Design Process 35
2.5.1 Protocol analysis 37
2.5.2 Effects of training, instructions and reminders on the experiment 42
2.5.3 Questionnaires 43
2.6 Summary of the Findings 47
3. COMPARING COMPUTER AIDED AND CONVENTIONAL DESIGN PROCESSES : A DESIGN EXPERIMENT 51
3.1 Constructing the Method 51
3.1.1 Experimental design of the protocol studies in the last decade: developing an overall perspective 55
3.1.2 Discussion of the methods and findings of key studies related with the research area 58
3.2 Method of the Proposed Design Experiment 68
3.3 Questionnaire Design 78
3.4 Findings of the Design Experiment 80
3.4.1 Analysis of the hypothesis-related protocol data 84
3.4.2 Analysis of the questionnaire-based survey 90
3.4.3 Evaluation of the findings and additional observations 93
4. CONCLUSIONS AND RECOMMENDATIONS 97
4.1 Interpretation of the Findings 98
4.2 Comparison of the Outcomes with the Previous studies 102
4.3 Future Research 102
CURRICULUM VITAE 163