Psychophysical influence of mixed-reality visual stimulation on sense of hardness

In a mixed-reality (MR) environment, the appearance of touchable objects can be changed by superimposing a computer-generated image (CGI) onto them (MR visual stimulation). At the same time, when humans sense the hardness of real objects, it is known that their perception is influenced not only by tactile information but also by visual information. In this paper, we studied the psychophysical influence on the sense of hardness by using a real object that has a CGI superimposed on it. In this experiment, we deform in an extreme way the CGI animation on the real object, while the subject pushes the real object using his/her finger. The results of the experiments found that human subjects sensed different hardnesses by emphasizing the dent deformation of the CGI animation.