Perception of finger angle position in grip-type haptic display based on grasping force

In this study, we propose a novel grip-type haptic display for controlling a virtual (or robotic) hand (Fig. 1). This grip-type haptic display enables us to control a virtual hand and perceive haptic information based on a reactive force and a spatially distributed tactile feedback. Because this proposed display does not need any actuators to produce the reactive force, a simple haptic display is developed. In a grip-type haptic display, it is difficult to perceive the finger position because of the fixed position of the user´s fingers. However, we consider that it is possible to perceive the finger position by means of the effort exerted. Therefore, we performed an experiment to discriminate the applied force and confirm that the force discrimination threshold was sufficiently small. Then, we constructed a one-fingered prototype using an electrotactile display. Using this prototype, we qualitatively confirmed that the reactive force with the spatially distributed tactile feedback can produce dynamically changing haptic information.