Archives of Design Research

The students who participated in this study have a weak science and engineering education. The design college that the students attended granted admission based on a specific drawing exam. Most students in this kind of design college had more experience with drawing rather than studying other subjects such as mathematics and science, which makes them reluctant to study interactive physical prototyping requiring technical knowledge. The subjects were thirty students attending <Interactive physical prototyping>, with seventeen and thirteen students in two classes. All of the students had taken the prerequisite class – <UX & interaction design 1>, in which they had learned and practiced user-centered design methods, and were taking <UX & interaction design 2>, in which they conducted three projects: service design, mobile design, and interactive media for five weeks each. <UX & interaction design 2> simultaneously proceeds with <Interactive physical prototyping> as presented in figure 1.

Figure 1 Class structure of <Interactive physical prototyping> and <UX & Interaction design>

To reduce the burden of studying technical issues in prototyping, this study uses Entry (2019), a block-based coding tool developed by KAIST (Korea Advanced Institute of Science and Technology), similar to Scratch, developed by MIT. The block-based coding tool uses a visual structure and logic, which allows everyone to easily access the code. In fact, Entry is mostly utilized in elementary schools. With its ease of use, the visualization of Entry helped the subjects of this study overcome their hesitance caused by their lack of technical understanding, as they are familiar with visual data and information.

Choi and Jung (2016) claim that the prototyping class should not only focus on the technology required for implementation of an interactive physical prototype but also on user experience. Balanced utilization of technical skills and a user-centered design method has been recommended by design educators. Nam (2006) designed an interaction design course with ten small exercises for practicing technical electronic skills and a final project integrating all knowledge acquired from the exercises. According to the students’ feedback in this study, the number of exercises was too high, and some students faced difficulties in electronic circuit construction. Similarly, the author also observed that the longer the students learned the technical skills related to electronics and programming, the more they lost interest in learning in class and faced difficulty in prototyping.

Considering the problems determined in recent studies and the present author’s teaching experiences, this study set two goals for the class projects: 1) gaining technical knowledge necessary for interactive physical prototyping; 2) developing the ability of utilizing technical skills in designing user experience; and 3) maintaining interest in learning through the course.

To achieve these goals, the first five weeks were spent understanding electronic materials such as breadboards, LEDs, resistors, and sensors; Entry as a software tool; and Arduino as a hardware platform with exercises.

The TtoX project, conducted by students between the sixth and tenth weeks, integrated small exercises for training each part of the electronic materials. This enhanced the students’ technical knowledge acquired from the first five weeks and reduced the number of small exercises.

In the TtoX project, students were first provided with forty-eight electronic materials – sensors, actuators, and LEDs – that could be connected to Arduino and enable input or output interactions (figure 2). Students were required to choose more than one material from each given input and output material and create a story for the defined user and context. The TtoX project required students to embody interactions with input and output elements by solving technical issues and to explain the meaning of their design in terms of user experience. The TtoX project was conducted in teams of two students. Group work reduces the burden of the project and enhances learning effects through teamwork (Nam, 2006).

Figure 2 Given materials in the TtoX project

The XtoT project was designed alongside the interactive media project of the <UX & Interaction design 2> class (figure1). In the XtoT project, students were asked to design an “Interactive Game” and create a digital prototype to allow people to experience how the game works. The XtoT project was a team-based project.

In short, in the TtoX project, students engaged in UX design following technical prototyping with given materials, while in the XtoT project, they first designed a UX concept and then prototyped it, as seen in Figure 3.

Figure 3 TtoX and XtoT projects

Both projects were designed for students to integrate their knowledge of technology and user experience.

After the two projects, we conducted interviews with eight students who had taken the class.

The TtoX project resulted in fourteen prototypes, while the XtoT project in twelve prototypes produced by thirty students. The documentations of all project outputs were collected and stored on an online server, and the simulations in project presentations were recorded on video. Some cases of prototype have been presented in this paper based on the interviewees’ answers.

One-on-one interviews were conducted with eight students. The interviewees’ answers were transcribed, followed by coding the data based on the grounded theory (Charmaz, 2006). First, each sentence in the data was open-coded. Thereafter, the extracted codes were clustered by meaning, such as action, technology, trouble, and negotiation. (Muller & Kogan, 2010).

An analysis of the interview scripts showed that the relationship between electronic materials and actions plays an essential role in students’ learning processes. Students often used it when describing difficulties they faced in the TtoX project as well as how the experience of the TtoX project helped them in the XtoT project. Students had no prior experience with coding or controlling basic electronic materials from breadboards to Arduinos and sensors. The TtoX project enabled students to understand how each electronic material works.

S01’s TtoX project was called Finger Wresting. In the working prototype, a finger’s push force bends a polystyrene stick, as shown in Figure 4. S01 described how they developed the concept as follows.

Figure 4 Finger Wresting - S01 concept in the TtoX project

“Servo motors are rotative but can pull and push something when connected to the appropriate structure. This means that the pulling force can be controlled with the parameter of the Servo.” – S01

Thus, S01 matched “servo motor” with the action of “pulling.”

S02 stated that he wanted to try as many sensors as possible, so his concept, “Sensitive Tanto,” uses four kinds of sensors – touch, vibration, sound, and tilt sensors – in an elephant doll, as shown in Figure 5. The doll reacts to the user’s action - talking, dropping, stroking its head, and shaking hands. In the interview, S02 stated that the TtoX project helped him learn how those sensors worked and he had no critical trouble in the next project.

Figure 5 Sensitive Tantor - S02’s concept in the TtoX project

Four students - S01, S02, S04, and S07– answered that they derived the user experience from the action in the XtoT project. They stated that they first came up with fun and creative interactions for interactive games. They made user experience stories using these interactions, then they iteratively modified the action and experience alternately.

In other words, the TtoX project gave the students the chance to learn what actions could be produced by technical materials. Understanding the relationship between technology and action helped the students match appropriate materials to a certain action, which is very important in designing the interaction and experience.

Compared to the XtoT project, the students faced many technical difficulties in the TtoX project. The students first had to select and purchase electronic materials to implement a working prototype with them. S03 described how he was shocked that the LED modules he purchased could not be connected to his Arduino because of a lack of digital pins. S04 mentioned the trouble she faced regarding the voltage of a string LED, which required an additional power supply. S01 recalled an embarrassing moment in which he found that the force of the servo motor was weaker than he had expected. S05 needed to abandon the heartbeat sensor she had purchased, which was neither sensitive nor accurate, to sense whether the user is walking or running. Interviewees also cited troubles they faced in determining purchasing appropriate materials online due to a lack of information and too many similar sensors and actuators.

“I never used breadboards and wires to make something before. The TtoX project made me become familiar with (+) and (-).” -S06

Like S06’s statement, many students learned how to solve the problems they faced in coding or controlling sensors and actuators. At first, most students connected the materials together, but then found that there is no way to know where an error occurs. Students then started to verify each step by checking each connection with an LED.

S07 used pressure sensors to recognize bad posture while sitting on a chair in the TtoX project (left of figure 6). In the next project, she developed a set of cooking toys and used pressure sensors to determine what is being cooked (right of figure 6). She stated that the experience of using a pressure sensor in the TtoX project helped her develop the cooking toy.

Figure 6 Pressure sensors used in the TtoX and XtoT projects by S07

“For the first five weeks, practicing exercise tasks with the professor gave us a basic knowledge of materials and coding. I thought I understood many of them at that time. However, in the first TtoX project, I did not know how to do anything. The first experience of coding in Entry and connecting sensors and LEDs was very helpful.” – S05

As S05 mentioned, the TtoX project was helpful in that it gave her the opportunity to become familiar with electronic materials and coding processes to embody the knowledge required for prototyping.

S06 described the process of developing her concept in the XtoT project as follows.

“When an idea for interaction was derived, we thought about whether we could implement it with Arduino. We tried to find fun and implementable interactions and made stories combining the interactions.” – S06

S08 illustrates the embarrassing moment of realizing he would have to develop a much simpler interaction compared to his original idea.

“We targeted kids for our interactive game. Changing sensors in the prototyping process resulted in a simpler interaction than our original idea. We believed that kids would not like the result, so we produced more ideas for richer interactions.” -S08

As seen in S08’s case, technical barriers made students negotiate the interaction and create more ideas to make richer interactions. Since the XtoT project was more focused on the user experience factor than the TtoX project, students struggled to design rich and creative interaction for target users. The technical difficulties they faced made the students iteratively modify the experience, interaction, and technology.

In the TtoX project, many students failed to implement their first idea. S05 needed to give up on her attempts to use a heartbeat sensor, which her team had curiously explored. As a result of wasting time with the heartbeat sensor, her team developed a simple interaction. In their final prototype, a slider brightens five LEDs linearly, presenting a story for children who want to be space explorers. Each LED represents a planet in the solar system and sliding indicates exploring from the sun to Mars (figure 7).

Figure 7 Simple interaction can dress user experience.

S04 had a similar experience. She also failed to combine two heartbeat sensors to recognize a couple’s level of affection for each other. After giving up using both sensors, she only had an LED that blinks in response to a heartbeat. Having read an article about how the hearts of old and unhealthy dogs are often irregular, she and her team finally developed a “pet health checking device” by enabling the sensor to be attached to the thigh of a dog’s hind leg with a Velcro string and visualizing the pet’s heartbeat.

These cases indicate that the purpose of the project in the prototyping class is not only to develop technical skills for using electronic materials and coding but also creating user experiences with limited access to technologies.