PhotoelasticTouch: transparent rubbery tangible interface using an LCD and photoelasticity

PhotoelasticTouch is a novel tabletop system designed to intuitively facilitate touch-based interaction via real objects made from transparent elastic material. The system utilizes vision-based recognition techniques and the photoelastic properties of the transparent rubber to recognize deformed regions of the elastic material. Our system works with elastic materials over a wide variety of shapes and does not require any explicit visual markers. Compared to traditional interactive surfaces, our 2.5 dimensional interface system enables direct touch interaction and soft tactile feedback. In this paper we present our force sensing technique using photoelasticity and describe the implementation of our prototype system. We also present three practical applications of PhotoelasticTouch, a force-sensitive touch panel, a tangible face application, and a paint application.