The objective of Virtual Aquarium is to promote good toothbrushing practices. The system is set up in the lavatory where it turns a mirror into a simulated aquarium. Fish living in the aquarium are affected by the users’ toothbrushing activity. If users brush their teeth properly, the fish prosper and procreate. If not, they are weakened and may even perish.

In this system, we used a 3-axis accelerometer that is attached to each toothbrush in a household. Since toothbrushes are usually not shared and each Cookie has a unique identification number, we are able to infer which user is using the system at a given time. Toothbrushing patterns are recognized by analyzing the acceleration data. The toothbrush is able to observe how a user brushes his/her teeth passively without requesting extra actions to play the game.

In this prototype, the ideal behavior was defined as follows:

• Users should brush their teeth at least twice per day.
• One session should involve at least three minutes of brushing.
• Brushing should involve patterns that ensure the teeth are properly cleaned.

User behavior is compared to this ideal and translated to feedback. We believe that the existence of an aquarium is in-artificial in a lavatory, but the aquarium enriches our daily life.

When a user begins to brush her teeth, a scrub inside the aquarium starts cleaning algae off the aquarium wall. At the same time, a set of fish associated with the user starts moving in the aquarium in a playful manner. When the user has brushed for a sufficient time, the scrub finishes cleaning and the fishes’ dance turns to a more elegant pattern. When the user finishes brushing, the fish end their dance and resume their normal activities. Both the activity of the fish and the movement of the scrub are designed in such a way as to give the user hints regarding the correct method of toothbrushing.

At first, the eggs are not very likely to hatch. If the user continues to brush consistently for a number of days in row, the incubation ratio increases. This way, the accumulated feedback gives clues to the correct behavior and attempts to maintain motivation over a period of time.

References

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  Nakajima, T., Kimura, H., Yamabe, T., Lehdonvirta, V., Takayama, C., Shiraishi, M., and Washio, Y. 2008. Using Aesthetic and Empathetic Expressions to Motivate Desirable Lifestyle. In Proceedings of the 3rd European Conference on Smart Sensing and Context (Zurich, Switzerland, October 29 - 31, 2008). D. Roggen, C. Lombriser, G. Tröster, G. Kortuem, and P. Havinga, Eds. Lecture Notes In Computer Science, vol. 5279. Springer-Verlag, Berlin, Heidelberg, 220-234. DOI= http://dx.doi.org/10.1007/978-3-540-88793-5_17
  
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  Nakajima, T., Lehdonvirta, V., Tokunaga, E., and Kimura, H. 2008. Reflecting human behavior to motivate desirable lifestyle. In Proceedings of the 7th ACM Conference on Designing interactive Systems (Cape Town, South Africa, February 25 - 27, 2008). DIS '08. ACM, New York, NY, 405-414. DOI= http://doi.acm.org/10.1145/1394445.1394489
  
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  Nakajima, T., Lehdonvirta, V., Tokunaga, E., Ayabe, M., Kimura, H., and Okuda, Y. 2007. Lifestyle Ubiquitous Gaming: Making Daily Lives More Plesurable. In Proceedings of the 13th IEEE international Conference on Embedded and Real-Time Computing Systems and Applications (August 21 - 24, 2007). RTCSA. IEEE Computer Society, Washington, DC, 257-266. DOI= http://dx.doi.org/10.1109/RTCSA.2007.45