shogoyamashita

[shogoyamashita]

Shogo Yamashita

‒ CV (curriculum vitae)

http://yamasy.com/publications/

‒ Research Plan

Tittle: Human-Computer Interaction in Underwater  Keywords: Underwater Entertainment, Virtual Reality  

We introduced a surround-screen swimming pool filled with transparent tracer particles for water flow visualization. The particles enable interactions in underwater entertainment by tracing the water flows by a camera. Moreover, swimming training users can see his/her swimming form displayed on the bottom with visualized water flows caused by strokes in the swimming pool.   The transparent tracer particles have a flat shape. For this reason, the tracking system sometimes loses the visualized particles when they are vertical since they look very thin from the camera for tracking. Moreover, the width and height constantly change. This shift in size reduces the stability of blob detection since we can not define the threshold for blob size. To avoid this issue, we have to invent ball shaped tracer particles. In addition, the flat shaped tracer particles become recognizable when they reflect light from the background. Water absorptive polymer used for growing plants are ball shape and becomes quite transparent in water without reflection. With some stress on the surface, the plastic also shows the characteristic of photoelasticity. We suspect water absorptive polymer showing photoelasticity by default without stress can solve the issue.

‒ Social Issues and the Research

Although swimming is considered to be one of the best exercises to maintain our health, swimming in a pool is normally monotonous; thus, maintaining its motivation is sometimes difficult. AquaCAVE is a computer-augmented swimming pool with rear-projection acrylic walls that surround a swimmer, providing a CAVE-like immersive stereoscopic projection environment. The system can also provide swimming training with projections such as record lines or swimming forms.

‒ GCL Plan in 2017

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. 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.