Verification of Haptic Illusions Using a Haptic Interface and Consideration on its Mechanism

In these days, a haptic interface, which is a force/tactile display device, is attracting great interest in virtual reality. With regard to this technology, researchers have reported ways to construct virtual environment and development of new devices with a unique mechanism but rarely explored the relationships between human perception and virtual dynamics. This paper suggests that it is necessary to clarify the relationships to provide more realistic force/tactile sensation for users. The main purpose of this study is to evaluate the force sensations displayed by haptic interfaces. This study focused on two haptic illusion phenomena, which are a haptic horizontal-vertical illusion and a size-weight illusion. Results of experiments using the haptic interface verified that such haptic illusions are reproducible in virtual reality. This implies that perceptual experiments can be realized using haptic interfaces, which may have potential to discover new haptic illusions. Further, this paper attempts to study the size-weight illusion by using functions of the haptic interface such as position and force sensing functions and propose a new hypothesis on the size-weight illusion. These results demonstrate that the effectiveness of haptic interfaces for perceptual experiments.