Paper Reading # 14

Reference:
PhotoelasticTouch: Transparent Rubbery Tangible Interface on an LCD and Photoelasticity
October 4-7, 2009 Victoria, British Columbia, Canada
Toshiki Sato, Haruko Mamiya, Hideki Koike, Kentaro Fukuchi

Summary

This paper talks about a system called PhotoelasticTouch that is tabletop system that is touch-based interaction. Three applications are described in this paper: a touch panel, a tangible face application, and a paint application. The main concern these researchers have is that current touch-based systems have rigid surfaces and therefore lack tactile expresiveness. The paper proposes elements such as no equipment that limits natural movement, flexible surface, surface should not block the image of the display, and interaction such include touching, pinching, kneading or pulling. They also describe other elements being proposed by other researchers in their systems. Most of these relied in IR camera and did not have tactile feedback in most. Photoelastic Touch is made up of an LCD, high speed camera, polarizing filters, and a transparent elastic body made of polyethylene or silicon rubber. The way PhotoelasticTouch works is by capturing deformations on the elastic polyethylene. The camera detects linear and circular polarized light from the deformations. The changes in pressure allows PhotoelastichTouch to infer direction without having to slide your finger. The three applications described are the Pressure-Sensitive Touch Panel, Tangible Face, and Paint Application. The touch panel senses multiple touches and also their perspective pressure values. With this application you can also rotate objects without sliding your finger. The tangible face is an application where you can deform a face image by applying different pressures with your fingers. The paint application is used by the user applying more pressure to draw thicker lines, and low pressure to draw thinner lines. In addition, the user can create elastic shapes such as stars, hearts, and circles to draw with.
Discussion
It is interesting to see that people are researching surfaces that allow pressures to be identified, and give the user more options rather than the now classic rigid surfaces. Graduate students were asked to use the elastic surface and most of them seemed to like it. However, we have to look into what type of applications a soft surface can be beneficial for.