Abstract
Shadows are usually natural and unintentional in real space. In virtual space, they play an important role in threedimensional effects and the perceived reality of the virtual space. An avatar’s shadow can have interactive effects with the avatar itself in the virtual space. In this study, we develop an embodied avatar system using avatar-shadow color expressions with an interaction-activated communication model. This model is based on the heat conduction equation in heat-transfer engineering, and has been developed to enhance empathy during embodied interaction in avatar-mediated communication. A communication experiment is performed with 12 pairs of participants to confirm the effectiveness of the system. The results of the sensory evaluation show that interaction activation is visualized by changing avatar-shadow color.