SKETCHING AND VISUAL PERCEPTION IN CONCEPTUAL DESIGN

Alexandre M. MENEZES1
School of Architecture, Federal University of Minas Gerais – EA.UFMG/ Brazil
Departament of Architecture and Urbanism, Catholic University of Minas Gerais – DAU.PUCMinas/ Brazil
Faculty of Engineering and Architecture, Fumec University– FEA.FUMEC/ Brazil


ABSTRACT: This research is concerned with conceptual sketches, visual perception and verbal description. Firstly, it focuses on the role of sketching in conceptual design and begins to question why conceptual sketches are considered a good medium for reflective conversation with one’s own ideas and imagery. Secondly, it focuses exclusively on the mental process involved in the analysis and verbal description of conceptual sketches. The empirical study examines how novice and expert designers might perceive different things from the same conceptual sketch and thus use different verbal descriptions, and what this might reveal about their different approaches to design. For this reason some experiments on visual perception, conceptual sketches and verbal description were conducted with expert and novice architecture students. The main objective is to verify to what extent the use of formal references such as line, square or circle and symbolic references such as describing a circle as a sun or a long oval as a sausage, help to understand how designers might think with sketches, while searching for a specific design solution. It also investigates which of the two types of images (non-architectural and architectural sketches) present greater potential for allowing the use of formal and symbolic verbal references, and why. The results show that, on average, the expert group used more formal and symbolic verbal references per minute than novices while describing the same images. The results also show that the non-architectural sketch was judged as easier to describe than the architectural one and gave rise to the use of more symbolic references. This can be seen to confirm earlier work suggesting that we find symbolic descriptions easier and more powerful than formal ones. The results also suggest that the expert students were more able to employ symbolic references to architectural concepts than the novice students. However, in many other respects there were few differences between the groups. This may in part be due to the limitations of the empirical methodology employed.
Keywords: sketching; visual perception; design cognition; drawings
1 – INTRODUCTION
In the conceptual stage of the design process, it is usual to find the use of some forms of graphic representation such as conceptual sketches and abstract diagrams. These conceptual sketches and diagrams are different from any other type of drawings employed by designers [1-3]. Some of the sketching does not follow ideas in the mind but instead, precedes them. In other words, designers quite often engage in sketching not to record an idea, but to help generate it. This is the kind of sketching this work refers to as conceptual sketching.

Some researchers [2, 4-9] have suggested that designers can see more information in the sketch than was invested in its making. It appears that designers discover new information and features in sketches as they are being made. This seems to allow designers to look at them from different points of view, especially in the early stage of the design process. Some sketches appear to provide visual clues for extracting new thoughts for the current design problem and for future use. However, it seems that designers only dynamically associate sketch marks with meanings when the association is needed, not when the marks are put down [7, 10].

Conceptual sketches seem to support the phenomena of emergence and reinterpretation during the early design activity. Emergence refers to new thoughts and ideas that could not be anticipated or planned before sketching. Reinterpretation refers to the ability to transform, develop and generate new images in the mind while sketching. Several researchers [9, 11-16] have suggested that the production of design ideas appears to depend upon the interaction with conceptual sketches. Perhaps the first step in understanding the designer’s mental interaction with conceptual sketches is examining what he/she can perceive while looking and describing sketches, and specially, how novices differ from experts on this.

1.1 – Novice and expert designers
A common ground from the literature about design expertise is that experts access different types and amounts of knowledge during the process of reinterpretation [12, 13, 17-19]. The results of several experiments show that practicing architects are more adept at perceiving functional features from the perception of visual features than students of architecture or non-architects. The interaction between novice and expert designers and conceptual sketches has been the subject of various research investigations [4, 11, 12, 15, 19, 20]. According to them, sketching appears to be not as helpful for novices as for experts designers and has helped experts for the purpose of developing new ideas, but failed to do so for novices. The objective here is to investigate differences in the way novice and expert architects interact with conceptual sketches.

This research also examine if expertise is related to the use of analogical reasoning while describing, and if so, how. One way to approach this problem is by asking what they see and perceive while looking at conceptual images. For this reason, this research intends to invite novice and expert architecture students to describe what they can see while looking at the same images. The question that might be asked is how they use knowledge and memory to create analogies when describing what they are seeing. The outcome may reflect differences in content and meaning of the same images between the two groups.

1.2 – Memory and precedents in design
The use of precedents to solve design problems seems to be central to the development of the design process, and one of the most important things for a designer. The use of precedents and analogical reasoning are strategies of which skilled designers heavily use [9, 13, 19, 21, 22]. Design precedents might be previous solutions seen on visits or holiday and they are usually considered either whole or partial pieces of design. They are also frequently presented through images in magazines, journals, books, the Internet and television. The suggestion is that the more people have seen, experienced and absorbed, the more the frame of precedent expands. It seems that this availability of precedent knowledge is likely to promote design creativity and appears to be motivating research in this area.

Reasoning by analogy and using precedents have been recognized as cognitive mechanisms that have the potential to bring forth prior knowledge that can support the acquisition of new information [19]. This suggests that the use of analogy can improve the quality of design and, in the early design stage, it seems to be a helpful cognitive strategy to approach design problems. The use of precedents and analogies are likely to allow the phenomena of emergence and reinterpretation of new thoughts and to promote design creativity.

This research is interested in the way designers organize, store and recall perceived information, and how this might be related to emergence and reinterpretation of new thoughts while designing. There is evidence that knowledge and procedures relevant to solving a design problem seems to be retrieved from long-term memory and used in short-term memory. The long-term memory appears to work using symbols, meaning and concepts rather than images. The study of the designer’s mental interaction with conceptual sketches is appropriate to investigate these issues. Conceptual sketches appear to support the use of precedent and analogical reasoning, allowing emergence and reinterpretation during early design activity.

2 – OBJECTIVES
The main objective of this research is to verify to what extent the use of formal and symbolic references used by designers during the description of conceptual sketches help to understand how they might think with sketches while searching for a specific design solution. Formal verbal references are geometric and physical features in the drawing, such as lines, squares or circles. Symbolic verbal references are analogies for something else that is not in the drawing, such as trees, sausages or sun. The use of formal and symbolic references during the description process might reflect the way designers think and the way new thoughts emergence.

This research also would like to investigate whether expertise is related to the use of formal and analogical reasoning, and if so, in what way. The mode of thinking employed is obviously very much dependent on the nature of situation. Therefore, thoughts used during the description process may be different from thoughts used during the design process. However it is suggested that identifying and classifying formal and symbolic verbal cognitive actions during the process of interpretation and description of conceptual sketches could enable future research to gain an insight into the designer’s reasoning steps. This could probably support the study of how designers interact with their own conceptual sketches and, specially, how sketching could allow unexpected thoughts. Therefore, this research seems to have inevitable implications for design education and practice.

This study intends to contribute to the investigation of how and when to teach drawing skills to design students. There is a lot of evidence from other research [4, 13, 17, 23, 24] to suggest that designers are able to get benefits from drawings because they were trained to use them in the way required to design, thus facilitating emergence and reinterpretation allowing new design ideas, and those who have not been trained in this way have less benefit from them.

3 – HYPOTHESES FOR INVESTIGATION
Differences in the cognitive activities may result in the difference in performance. A high quality in description is not expected, but if experts use their prior experience and knowledge in approaching drawings, they should be both better at analysis and description of conceptual sketches than novices. Therefore, it is hypothesised that the quality of the description for the expert architecture students would be higher than for novices because of their ability in recognizing features in visual displays.

It is also hypothesised that experts use their memory and previous knowledge more effectively to create analogies using more formal and symbolic verbal references to describe what they are thinking. Expert students should be able to use more formal references to describe geometric features and physical composition of drawings, as well as symbolic references using precedents and analogies to something else external of the drawings. The use of formal and symbolic verbal references during the description process might reflect the way they think and the way new thoughts emerge. If this proves to be correct, this could enable future research to gain an insight into the designer’s reasoning process.

4 – EMPIRICAL RESEARCH
This research has developed an experiment with first year (novices) and last year (experts) architecture students related to interaction and description of conceptual sketches. The experiment requires architecture students to describe conceptual sketches to another student who cannot see the images, but must reproduce them from the verbal description. The subjects are invited to describe what they are seeing and the focus is to investigate differences in the way the two groups of students think with drawings, or at least, about drawings.

The question that might be asked is how they perceive and describe the same image, and especially, how they use formal and symbolic references to complete the tasks. The answer to this question seems to reflect differences in cognitive activities between the two groups of students. Although this is not a study of sketching during the actual process of designing, the output of this experiment is clearly the result of a mental synthesis process, an important activity in the design process.

4.1 – Subjects
A total of sixty architecture students were involved in this experiment. They were all from the School of Architecture at The University of Sheffield and they were divided into two equal groups - First Year and Diploma Year students. All subjects were volunteers who received neither payment nor course credits in return for their participation. All students were approached in the studio and the intention was find them in their own work place. Looking for the most spontaneous descriptions, this research decided not to inform the students about the experiment in advance. This might prevent them for preparing themselves to describe images in a specific way, which would probably camouflage the results.

4.2 – Experiment
The experiment is divided into thirty sessions. Each session involves two students called subject A and subject B, and is divided into different tasks. The voices are recorded and their action videotaped so that not only their description and sketching activity in the task, but also their pointing gestures and doubts can be visible. At the beginning of the experiment, subjects receive a set of general instructions about the tasks and procedures.

4.3 – Tasks
There are four different tasks: Two description tasks, one remembering task and one review task at the end of the session. During the description tasks subject A is shown the two different images separately (non-architectural and architectural sketches) and has to observe them for later verbal description to subject B. Subject A can look at the image while describing, since the experiment’s interest is not on how he/she memorizes the image but how he/she interacts with knowledge and memory to create analogies for interpretation and description of thoughts. Therefore subject A does not need to memorize the images but does need to describe them in his/her own way.

Subject B has to listen to the description and draw what he/she understood from that. Subject B cannot ask questions to subject A in order to better understand the descriptions and draw the image, and subject A cannot see what subject B is drawing. The decision to non-conversation between students was based on evidence from the pilot studies. According to these pilot studies, the conversation between subjects did not allow for a spontaneous and free description from the subject A, creating a strong tendency for formal and geometric verbal references and an inhibition for symbolic references and analogies. Therefore, in order to gain a better description, it was decided that subjects could not converse.

After the description tasks, there is a remembering task, where subject A is asked to draw from memory what he/she described to subject B. The duration of this task depends of each subject and there is no interference between the tasks. The review task is the last one. At the end of each session, subjects A and B are asked to view all the images and drawings produced and comment on the experience. Whilst watching their own videotape, subjects are asked to review the experience focusing on what, why and any doubts experienced while describing or drawing each portion of the sketches. The focus of this review stage is to identify the easiest and hardest sketch to describe and the reasons for this.

4.4 – Apparatus and stimuli
The experiment is designed for a specially prepared room divided into three parts. In one part, there is a table where subject A sees the two sketches. Camera 1 records subject A examining and describing the sketch. A workspace (desk and chair) with drawing material (paper A4-size, black pen) is provided for the subject B’s use in another part of the same room. There is also a workspace (desk, chair and control panel) for the experimenter’s use. The experimenter controls the video and sound through monitors (Figure 01). The sketch to be drawn is concealed from view in the workspace by a screen dividing the viewing and working areas. While subject B is sketching what he/she is hearing, two cameras are recording from different angles. Camera 2 focuses on the sketching area and subject B’s hands while Camera 3 is placed in front of subject B to register his/her movements and gestures. The subject must not feel the experiment is a test, but more or less like an interesting game with no concern for right or wrong responses. At the beginning of the experiment, participants receive a set of general instructions about the tasks and specifics instructions to each subject.

4.5 – Images
There is a very general agreement that abstract representations seem to facilitate the use of analogy [25-28]; therefore the images must be abstract and not formal representations of known things. These types of images can be compared with Rorschach cards, which, due to the complexity of their shapes, are interpreted in many different ways by those who contemplate them. The images used in the experiment belong to two different groups: non-architectural and architectural sketches. Basically, the architectural sketch belongs to the design context, that is, to the process of searching new thoughts for a design solution. The non-architectural sketch belongs to an art context and does not relate to design. In order to facilitate the interpretation of the data and allow comparisons between groups, this study decided that all subjects must describe the same images. The sketches must be from other authors than the participants. The non-architectural image is a sketch from Paul Klee/1939 (Double Island) and the architectural one is a sketch from Mies van der Rohe/1935 (Hubble House study). The reason for this is to allow participation of non-architects in the same conditions as architects and compare the groups.

The reason for using these images was to investigate how they might give rise to both formal (geometric and physical features) and symbolic (analogies to something else) references in the descriptions, and why. The images are described separately and subjects have some time to observe them to create analogies before verbal description. It is expected that a variety of displays will emerge in imagery and its description may be equally diversified.

4.6 – Handicap and limitations
This section is concerned with the limits of the methodology developed and presented in this study. Some limits represent potential problems that can influence the results and conclusions. For this reason, some of them are identified here for further analysis and possible future corrections. The first limitation is related to the procedures of the experiment. Such procedures (inviting people to describe what they are seeing) need to be applied and analyzed with care. They tend to confuse the process of discovery with that of expression or communication of ideas. For example, a person might be skilled at generating ideas, but poor at reporting or describing them. This is the main handicap of protocol analysis in design.

The experiment was designed to study the thoughts involved in the interaction and description of conceptual sketches, and not to examine the actual sketching activity during the design process. Thoughts used during the design process may be different from thoughts used during the description process, and this can represent a mistake in the methodology. However, as established, if it is possible to identify and classify verbal cognitive actions used during the process of interpretation and description of conceptual sketches, this could support future research on designer’s reasoning process.

Another limitation seems to be the use of only two images in the experiment. Ideally we would like to use a large number of images, but the evidence from the two pilot studies strongly suggested this was unpractical within sensible lengths of experimental sessions. According to the pilot studies, two images seem to be a comfortable limit for spontaneous description in one session. Therefore, it was decided to use only two images, in order to allow for a better and more comfortable description. The specific culture of the students certainly represents other limits for this research. The different cultures of the students can influence the descriptions and the use of formal and symbolic references. Some foreign students mentioned difficulties with the language and not with the analysis of the images. As the focus of this research is concerned with the description and verbal references used, this clearly represents a disadvantage and a limitation for the findings.

5 – ANALYSIS OF THE PROTOCOLS
Many systems for describing and analysing design protocols have been developed over recent years [12, 29-32]. Any system of protocols subdivision must to some extent depend upon the overall paradigm used to describe the design process. It must be assumed that this will also apply here in analysing descriptions of images. The method developed in this study was adapted from the analysis method proposed by Suwa and Tversky, and Suwa, Purcell and Gero [12, 30]. It is based on the cognitive actions of subjects and intends to inspect their thoughts and behaviour on perceiving, remembering and describing conceptual sketches. As many previous protocols analysis methods have done [9, 13, 30] this study used retrospective reporting that employed both segmentation and encoded categories of cognitive actions. To support and supplement the verbal protocols, the analysis adopted the visual data from videotapes, which had recorded participant’s pointing gestures in reporting.

The verbal data were the main target of this analysis. They were collected from video and audiotapes of the experiment and are composed of thirty sessions and sixty descriptions. All sessions and descriptions were analysed separately. Clearly, to make sense of these protocols they need to be broken down into segments, which can be categorized and compared. This will also enable an analysis of sequence and proportion of events in the protocol as a whole. However, a key problem here is exactly how to subdivide the protocols into segments.

5.1 – Segmentation
It appears that a fruitful way of analysing a design process is to decompose an entire process into its smallest components and to focus in the links among these components [11, 12, 30-32]. According to Gero and McNeill [31], the designer’s activity can be considered as consisting of a sequence of actions, what they called micro strategies. These micro strategies seem to be similar to the concept of segment, presented by Suwa and Tversky [12]. It appears that the number of different segments that can be identified in a design process is dependent on both the designers experience and on the complexity of the problem. Bilda and Demirkan [32] also agree with others and argue that each designer’s section has a different number of segments, depending on variables like the designer’s way to problem solving, procedure of decision making, learning effects and so on.

This study considers two basic ways to segment design protocols. The first is to divide protocols based on the subject’s intention. A change of subject’s intention or the contents of their thoughts or their action flags the start of a new segment. Consequently, a single segment sometimes consists of one sentence, and sometimes of many [11, 12]. In this way, a segment whether consisting of one sentence or many, is defined as one coherent statement about a single item. According to Goldschmidt [11] a segment, a ‘design move’, is an act of reasoning which presents a coherent proposition pertaining to an entity that is being designed. Therefore, an entire protocol for a subject could consist of several sentences or segments. Another way is to divide protocols based on verbalization events such as pauses, intonations as well as syntactic markers for complete phrases and sentences. Therefore, pauses or syntactic markers flag the start of a new segment. In this case sentences or phrases or even fragments of phrases will be the segment [33]. Because of the objective of the research, the second way is adopted in the analysis. So a segment is defined based on verbalization events as phrases, sentences and even their fragments. The focus is to investigate how subjects use their knowledge and memory to create analogies and references to describe what they are seeing and thinking.

5.2 – Cognitive actions categories
A segment could include several cognitive action categories. Suwa and Tversky [12]initially suggest that segments can be categorized based on many cognitive actions that depend on the types of information they utilise. However Suwa, Purcell and Gero [30] suggest a richer epistemology of these categories classifying them into four subcategories: Physical; Perceptual; Functional and Conceptual. Based on this previous research, this study intends to determine a set of cognitive action categories into which the segments could be cast. It is not claimed that the cognitive action categories studied here cover all the cognitive actions of the participants, but it was possible to analyse all the sessions in terms of these cognitive action categories proposed. Therefore, two groups of cognitive actions were established: Physical and Verbal. This research concentrates only on the analysis of verbal cognitive actions used by the participants during the task. However, in the videotapes it is possible to see a strong link between verbal and physical cognitive actions, which suggests a very interesting field for new research.

The verbal cognitive action category considers that the subject solves the problem in terms of general, features and reflective descriptions. General references are related to paper information (A4, portrait or landscape), to size (big, small, cm, mm), to spatial relations (left, right, above, below), to general view (quantity or grouping) and to conclusive comments (‘that’s all’; ‘that’s the best I can’). Feature references are divided in two groups: Formal and Symbolic. Formal references are related to physical and geometrical characteristics. They include descriptions as square, oval or line. Symbolic references are related to analogies and elements that are not represented in the drawings. They include descriptions as box, sausage or wall. Reflective references involve judgement as difficult, easy, hard or simple. They also involve remembering (‘that I told earlier’, ‘remember that’, or ‘you just drew’), reflecting (‘I think’, ‘I hope’, ‘that’s the best I can’, ‘that’s all’) and recapitulating (‘I’ll try again’, ‘you should have’ or ‘it’s basically composed’).

6 – RESULTS AND DISCUSSIONS
The most immediately feature of these results is the enormous variety in responses and it was expected in this type of experiment. This work supports Bartlett and suggests that uniformity and simplicity of stimuli are no guarantee of uniformity and simplicity in response, particularly at the human level [34]. There is no doubt that the same stimuli are different for each subject, and obviously the records made in recall are different also. Two general patterns emerged from the results. First, few statistically significant differences between groups and sketches were found when compared on average. Second, large variations between individual subjects were found related to many of the issues. For these reasons, both an analysis per group on average and an alternative analysis using a comparison between individual subjects were conducted. All the results taken together present an overview regarding the groups and sketches.

This lack of significant differences was surprising and both unexpected and interesting result, as it is reasonable to expect differences between the two groups. However, some reasons as to why these results should be treated with caution will be presented comprehensively later in this study. There are however some important statistically significant differences between the groups related to the number of segments per minute, the number of verbal cognitive actions per minute and the use of formal and symbolic references while describing the same images. The statistically significant differences found enabled further analysis on the interaction of description, the image described and the drawing produced between the two subject groups.

6.1 – Why were there fewer statistically significant difference between groups?
No statistically significant difference was found related to description times, number of segments, number of verbal cognitive actions, and final ranking of sketches. These might be seen to be surprising and interesting results that appear to bring some views expressed in the design literature with respect to differences between novice and expert designers into question.

There are at least two ways in which to interpret these findings. First, this suggests that perhaps there is no significant difference between the two groups related to these issues. The experiment was designed to examine different thoughts involved in the process of description of conceptual sketches, and not in the actual process of sketching and designing. It appears that the most significant differences between these two groups – novices and experts – could be the thoughts involved in the process of sketching while looking for a specific design solution, and not describing a sketch within a non-design context. The second way to approach these findings could be ask to relevant questions related to the methodology and procedures adopted in this research.

The first question could be related to the experiment itself. The experiment focused exclusively on the mental process involved in the interpretation and verbal description of conceptual sketches, and not on the actual sketching activity neither on the design process itself. However, the tasks clearly involved mental synthesis, as participants were asked to analyse the images and describe their thoughts. Mental synthesis is considered to be fundamental for any design activity. If mental synthesis is one of the core aspects of design process, then expert design students should be better at both analysis and description of conceptual sketches than novices. Was this research wrong in assuming that novices would do these tasks differently to experts?

Another possible explanation could be related to the subject groups. Only architecture students formed the groups, and even first year students might be seen to belong to the same culture. This probably represents a limitation for the findings. It seems reasonable to suggest that a major difference could be obtained between very expert architects with at least 20 years of professional practice and novices from a population of first year law students with little sketching experience.

According to previous cognitive literature, individual or common interests could also affect performance during the description tasks (Bartlett 1950). At the time of the experiment, First Year students were much easier to invite to participate than Diploma Year students. Expert students were heavily involved with other work and preoccupied in the studio. Another explanation could be related to the standard of students, which was not matched between groups. It is possible for example, that the first year students were the top students of the group and the diploma students were not. However, as it was difficult to find a clearly relevant way to identify the better students, they were randomly invited.

7 – CONCLUSIONS AND IMPLICATIONS
Evidence from both cognitive psychology and design literature supports the idea that architects, especially in the conceptual stages of the design process, have a strong interaction with their own sketches. This interaction with drawings seems to be more relevant to designers than the physical skill to draw. There are some studies that already indicate what role sketching may play in design [11, 14, 15, 17, 20, 35, 36]. However, there have been a small number of empirical studies that have focused on the role of these representations in the early design process and, despite their importance sketches seem to have a perceived low status.

This research revealed that expert architecture students used more verbal cognitive actions per minute than novices while describing the same images. This suggests that the way they describe and the way they use formal and symbolic verbal references might reflect the way they think and the way new thoughts might emerge during the interaction with sketches. If this is right, this could support future research to approach the designer’s reasoning process in a more rational and critical way. The results appear to suggest that the designer’s interaction with sketches may be, in part, tied to the facility to associate them with something else using analogy. However, there is no evidence yet if this is also true in a design context and this is clearly indicative of the next step to examine.

7.1 – Future work
Because of the objective of this research, it concentrates only on the analysis of verbal cognitive actions used by the participants while describing the images. However, in the videotapes it is possible to see a strong link between verbal and physical cognitive actions, which suggests a very interesting field for new research. The question that might be asked is if there are connections between the participants’ mental activity and their body language while analysing and describing conceptual sketches. If yes, what might this suggest about mental synthesis, body language and sketching activity during the design process? Are there differences between the two groups and the two images?

This research focused on the participants as a group and did not deeply analyse just one subject separately. Based on the results, it seems to be possible to investigate the interaction of the best drawing produced, that is, the one that got a better rank from the referees, and the description that it was originated from. Is the better rank related to the length of the description or to the number of verbal cognitive actions used by the subject? Is it related to the number of formal and symbolic references used during the description? The longest and the shortest descriptions and their influence in the drawings produced could also be examined. The descriptions that used more and less number of verbal cognitive actions, more and less formal/symbolic references and their impact on the drawings produced could be compared.

During the experiment the participants were required to remember and to draw by memory what they described. However, no analysis was conducted to investigate the relationship between remembered information and its previous description. Did the subjects remember the images in the same sequence as they described them? Is there any connection between the way we describe things and the way we remember them? If yes, how can this help to understand how designers’ might remember relevant information while searching for a design solution? What are the differences between novice and expert designers related to this? All these considerations suggest interesting fields for new research.

7.2 – Future implications
This research suggested that identifying some verbal cognitive actions during the process of interaction and description of conceptual sketches could support future research into the designer’s reasoning process while sketching, and might inform as to how they approach design. This could also help to study how designers interact with conceptual sketches and how they might use drawings to allow new and unexpected thoughts to emerge. Therefore, the preceding discussions seem to have inevitable implications for design education and practice, implications that are essential for researchers to address and articulate.

This research intended to contribute to the investigation of how and when to teach drawings skills to designer students, and especially, how to use conceptual sketches to allow unexpected ideas to surface while sketching and examining them. The results of this study suggest that the facility to associate the sketches with something else seems to promote the interaction with them. These appear to be fundamental issues for teaching drawings skills on schools of architecture. However, there are some questions that seem to remain unanswered. What are the implications of this on CAD? Can computers also support this early design activity?

The general agreement between researchers seems to suggest none really intend to completely replace freehand sketching at the conceptual stage [7, 12, 20, 37-40]. There is no reason to assume that, if emergence and imagery can be amplified using sketches, they also can be further amplified using a computer. This research intended to contribute to the better understanding of how designers think, perceive and describe sketches, and then, motivate new research for computational tools that possess the functionality of enriching perception. The suggestion was that such computer tools should be intuitive and their use should not require specialized knowledge to facilitate emergence and reinterpretation.

It can be assumed that free hand sketching is still prevalent in the conceptual phase of design, and computers can support freehand sketch activity, but more work and more research is needed. Inevitably the new generation of computers should hold enough knowledge to be able to interpret conceptual sketches and to approach design problems. However, it seems to be necessary that these computer tools allow designers to communicate with them in a much more natural form of language and they should be able to infer meaning and intention and then, they could indeed be a useful partner in the design studio. Until that time, this study is in agreement with Lawson and concludes that computers can assist with various jobs for people in design, but whether this can really be called computer-aided-design remains questionable [35].

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