4.1 Comparative analysis of the concept generation process
The concept generation process was comparatively analyzed by time based on the type of design tools. The significant difference between TA and TB was found in the initial ideation phase (ID). Initial ideation phase configured at an average at 35.9% in TB, while initial ideation configured at 50.3% in TA. On the contrary, during the concept generation process the participants spent longer time on concreate ideation (CI) and make decision (MD) in TB. While about 6.9% of the time was spent in MD phase in TA, TB accounted for 11.6 %, that is, nearly twice more.
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Through the analyzing the data in the process of design concept generation in TA and TB, it was found that the cognitive design actions that occur during initial ideation phase, concrete ideation, and make decision need to be closely analyzed. Therefore, based on notable differences in the design concept generation process, we analyzed the remarkable cognitive design actions and design thinking that occur in the design process. In addition, the close linkage between cognitive design action, design thinking and its characteristics was analyzed in more detail.
4.2 Comparative analysis of cognitive design actions
The protocol analysis of cognitive design actions revealed differences in the total number of actions (Table 4). An analysis of the types of cognitive design action showed differences in the frequency of physical action and perceptual action between TA and TB.
Between TA and TB, there was a significant difference of in the PM (Make depictions) categorie in physical action. When using the 3D sculpture tool, the participants’ rates of PM (24.7%) were much higher than when making a sketch without 3D sculpture tool (11.8%). The difference was in conceptual design action, in which the designers undertook more conceptual thinking when using the 3D sculpture (19.6%) tool than when making a conventional sketch (14.1%). A significant difference in conceptual design action shows that aesthetic evaluation (CE) accounted for nearly 2 times more in TB (9.9%) compared to TA (5.6%). More repetitive evaluations of the development process occurred when participants used the 3D sculpture tool than when they made sketches without the 3D sculpture tool. When using the 3D sculpture tool, participants iteratively paused and reviewed their work to evaluate the whole design and determine whether the development process should continue or stop. Participants continually evaluated the aesthetic factors of their drawings using a digital tool and modified them or developed a new idea through rigorous self-critique. The immediate visualization of an idea with a 3D sculpture tool involved review activities such as “self-critique” and “aesthetic evaluation” for idea generation. Participants identified the 3D shape from initial drawings and developed a specific 3D drawing using a 3D sculpture tool and recognition of a new idea and value occurred during the phase of refining critiques about the visual and aesthetic factors using a digital tool.
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4. 3 Comparative analysis of types of design thinking
As a result of comparative analysis of types of design thinking, the key features of design thinking were observed in TB were visual thinking (VT) and analogical thinking (AT). The frequency of visual thinking and analogical thinking were higher in TB (Table 5). In addition, as shown in Table 5, stimulus factors (SF) and making decision (MD) also exhibited higher frequencies in TB.
However, cognitive thinking (CT) has emerged more frequently in the type of design thinking in TA.
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This data analysis result enables the inference that visual thinking and analogical thinking may be linked to the frequency of stimulus factors and making decision phases. From the result, it can be deduced that immediate visualization of the idea generation process can form an important part of design thinking. This reasoning was further strengthened through the analysis of design thinking flow that show the interaction and linkage between design actions and design thinking.
4.4 Analysis of design thinking flow
The design thinking-flow charts (Figures 6) provided below were illustrated to analyze by episodes in design concept generation process, and the features of design actions and design thinking types. At least one key event or episode would consist of a single phase, therefore, every major episode of the design process was initially considered. We observed verbal and visual information in the experiments, content of the segments, word and sketch density of the segments and incubation periods for the segment from retrospective protocol to confirm the design thinking flow. The coding scheme is in three parts: design concept generation processes, cognitive action modes, and design thinking. To understand the role of visual stimuli of a 3D sculpture tool in the design thinking process, we analyzed the relationship between design thinking (divergent thinking, convergent thinking) and design thinking types (visual thinking, analogical thinking, cognitive thinking) in the design development process. Figure 6 summarizes the thinking types and the relationship in between design thinking and design actions the various stages of idea generation and visual image implementation.
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According to analysis of design process by the design thinking-flow charts, new ideal source and make decision phases occurred more frequently by visual stimulating with 3D sculpture tool. Dealing with the conceptual aspect of the design and the tendency to focus on visual abstraction and exploration of visual features through simulation for design ideation and conception were also recorded mainly in experiments using a 3D sculpture tool. We found that early initial ideation has various transformational moments by visual stimuli with 3D sculpture tool. For example, during the phase of drawing an idea using a 3D sculpture tool, the participants tended to focus on the visual-spatial features of design elements such as colors, materials, and shapes by stimuli factors. As shown on figure 6, after creating a new visual form by a 3D sculpture tool participants derived various metaphorical keywords such as “flower brunch, birds eyes’ view, lavender pink and olive green” (P1TB), “owl, wolf, face, bon-structure, cycle, metal, wire, futuristic, classical transforming” (P2TB), “split, broken, tornado, whirlwind, incompleteness space” (P3TB). New design idea drawings related to them also appeared more frequently. A 3D sculpture tool encouraged participants to integrate and apply new ideas and the visual aspects of designs to generate new drawing ideas.
In addition, as the result of analysis verbal and visual data and participants' design behavior in the conceptual design process as design thinking-flow charts and time units; it was found that that the larger numbers of physical actions such as drawing new design ideas and noting new keywords were higher in the design process using 3D sculpture tool (Table 6).
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According to analysis of analyzing sequence of design thinking-flow in TB (Figure 6), we also found that the visual stimulating by 3D sculpture tool could facilitate the rapid change and modification of design direction. It was discovered that when a new stimulus factor was created by 3D sculpture tool, it caused analogical thinking and visual thinking, resulting in the creation of new keywords and new ideal source. In addition, the new ideas thus generated are converged through cognitive thinking, resulting in a process of new evaluation and make decision, thus generating “transformative linkage” in the design process. Many thought stages were accrued, and it connected in a variety of ways by immediate stimulation.
Furthermore, visual thinking and analogical thinking occurred sporadically and interacted with each other were observed. Participants had higher frequency levels of analogical thinking and visual thinking in relation to making decision had a high frequency of both subsequent evaluations and non-sequential evaluations. In other words, the cognitive design process was advancing through active image reasoning and evaluation. After the visual stimulus by a sculpting tool caused, it can be found that the visual thinking, making decision and analogical thinking occurs. The cognitive design actions connected and interacted with visual thinking and analogical thinking caused new sources of ideas such as new keywords, new visual aspects of designs to occur in the process. The ideal sources based on analogical and visual thinking contribute transformative linkage on design thinking flow.
Figures 7 was shown the characteristic of design thinking process by divergent and convergent thinking in the design concept generation process using 3D sculpture tool. The X-axis shows the flow of time, and the Y-axis shows the degree of immersion that was estimated by continuously focusing on design thinking types. The sporadic design thinking process is a characteristic of the design concept generation process using 3D sculpture tool that the process of divergence and convergence through short term commitment and repeatedly several times tends to take. the process of divergence and convergence are repeated over a short cycle in the design thinking process. In addition, the process of convergent thinking that integrates ideas using intuition such as divergent thinking and verifying ideation were performed smoothly.
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