Photoelastic Tracer Particles: Visualizing Water Flows with Transparent Tracer Particles for a Surround-Screen Swimming Pool

A surround-screen swimming pool can realize various forms of underwater entertainment and enable enhanced swimming training with supplemental visual information during underwater activities. However, one of the big challenges for such an augmented swimming pool is user interaction because the surround screen and water can make existing position-tracking methods unusable. In this paper, we propose a water flow visualization method with transparent tracer particles to enhance interactivity. We used an optical property of clear plastics called birefringence that provides vivid colors on transparent tracer particles when they are between two circular polarization sheets. Tracing objects using cameras in front of a complex background is not a stable method, but this technology enables visible tracer particles on a simple and dark background. For underwater entertainment, the water flow tracing works as a user interface because the transparent tracer particles do not stop users from viewing the images on the screen. For enhanced swimming training, swimmers can view visualized water flow caused by strokes in the augmented swimming pool. From the results of our stability evaluation of water flow tracing, the proposed method is valid even for complex backgrounds. We also conducted a feasibility test of the enhanced swimming training. According to the trial, the tracing particles could visualize the water flow caused by the strokes made by a swimmer.

 

Publications

  • Shogo Yamashita, Shunichi Suwa, Takashi Miyaki and Jun Rekimoto, “Water Flow Measurement Technology Assessing Spatial User Interaction in an Underwater Immersive Virtual Reality Environment”, The 25th IEEE Conference on Virtual Reality and 3D User Interfaces (IEEE VR2018), March 18-22, 2018, Reutlingen, Germany. (デモンストレーション発表) Organizer: IEEE

 

  • Shogo Yamashita, Shunichi Suwa, Takashi Miyaki, Jun Rekimoto, “Investigation of Tracer Particles Realizing 3-Dimensional Water Flow Measurement for Augmented Swimming Training”, The 9th Augmented Human International Conference(AH2018), Article No. 2, February 7-9, 2018, Seoul, Republic of Korea. DOI: 10.1145/3174910.3174918 Organizer: IEIE sigAH (ICPS published by ACM)

[Best Paper Award]

Patents

  • 特願2018-12298、“3次元流体計測法”、1月・2018年

Grants

  • JST (科学技術振興機構) ACT-I、300万/1.5年、10月・2017年 水泳プール中の水の流れを3次元計測する技術の開発