Title: Patina Engraver: Visualizing Activity Logs as Patina in Fashionable Trackers
Authors: Moon Hwan Lee, Seijin Cha, Tek Jin Nam
Institution / lab: KAIST (Korea Advanced Institute of Science and Technology), Department of Industrial Design, CIDR Lab
Research Questions:
How can activity logs be visualized physically using patina rather than digitally?
Can embedding activity data directly into the wearable itself improve the motivation to exercise, emotional attachment to the tracker, and social interaction?
Does treating activity trackers as fashion objects change how users experience and value them?
What Is Already Known:
Activity Tracking: From previous HCI research, it has been noted that people use activity trackers to ask about their history, goals, and status (Weigel et al., 2015).
The paper states that users also often lose interest over time as the tracking becomes routine.
Most trackers rely on mobile apps and use graphs and numerical values.
However, emotional and long-term motivation remains a challenge.
Activity trackers are worn publicly but are only used as technical, not expressively.
Visualization of Activity Data: Prior work explored virtual media (growing pets or using interactive displays) to physical artifacts like 3-D printed objects, but each has its limitations, from being slow and impractical to representing only one moment of data or visualization being separate from the wearable itself.
Fashionable Wearables: It is already known that wearables have both a technological and a fashionable function. Current trackers are visually generic, and some companies collaborate with fashion brands, but only to change the appearance, not how that data is experienced.
Methods: How the Researchers Answered the Questions:
The researchers designed the Patina Engraving System to engrave the user's data directly into the tracker using a piercing technique that creates dot-based patterns similar to patina (natural aging marks on materials).
The Patina Engraving System consists of two components: the tracker itself (a wristband with a Fitbit sensor) and an engraver, the machine that inputs the design onto the wristband.
Method: Had 8 participants from the same badminton club for a 5-week period, where the trackers were engraved twice a week with the steps, calories, sleep, and walking distance info. They conducted the trial in such manner to get rich insight from the experience rather than statistical generalization.
Findings:
The participants became more motivated to exercise because they wanted to create visually appealing patina patterns. The permanence of the engraving created pressure to stay active and also served as a reward system.
Participants also developed emotional attachment to the trackers. They described the engravings as symbolic objects that represented their personal history and achievement.
Third, the physical visibility of patina encouraged spontaneous social interaction. People asked questions about patterns, compared trackers with friends, and shared stories about their activity history. This created face-to-face social engagement without the need for social media sharing or virtual connections
How Others Can Use These Results:
Other researchers can use these results to design future wearables that integrate physical data visualization instead of relying only on screens. Designers can apply the concept of patina to other domains, such as rehabilitation devices (e.g., quit-smoking), health behavior tracking, or even financial spending tools. As the authors state, “All fashionable items have physical, psychological, and social functions” (Lee et al., 2015), supporting the idea that designers can rethink wearables as personal artifacts rather than purely technical devices.
What We Now Know:
This research shows that physical visualization of data can meaningfully change how users relate to their devices. Embedding personal history directly into wearable materials can increase motivation, emotional attachment, and social interaction. We used to only think of activity data as digital information. Now we know it can be treated as part of a lasting, fashionable physical object.
Interesting Findings:
What stood out to us was that the tracker, over time, became more of a personal artifact rather than just a device. It became a symbol of the user's achievements and held a personal history of how they've done.
This concept could also be applied to other domains, such as financial tracking, where a “patina wallet” could visualize spending behavior and encourage reflection through emotional and symbolic feedback rather than exact metrics.
Reference
Moon-Hwan Lee, Seijin Cha, and Tek-Jin Nam. 2015. Patina Engraver: Visualizing Activity Logs as Patina in Fashionable Trackers. In Proceedings of the 33rd Annual ACM Conference on Human Factors in Computing Systems (CHI '15). Association for Computing Machinery, New York, NY, USA, 1173–1182. https://doi.org/10.1145/2702123.2702213