A method for evaluating motion sickness induced by watching stereoscopic images on a head-mounted display
Hiroki Takada, Kazuhiro Fujikake, Tomoki Watanabe, Satoshi Hasegawa, Masako Omori, Masaru Miyao · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2009
It has been reported that even users of virtual environments and entertainment systems experience motion sickness. This visually induced motion sickness (VIMS) is known to be caused by sensory conflict, for instance, the disagreement between vergence and visual accommodation while viewing stereoscopic images. The simulator sickness questionnaire is a well-known tool that is used herein for verifying the occurrence of VIMS. We used the SSQ and also quantitatively measured head acceleration and sway of the center of gravity of the human body before and during the exposure to stereoscopic images on a head-mounted display. During the measurement, the subjects were instructed to maintain the Romberg posture for the first 60 s and a wide stance (with the midlines of heels 20 cm apart) for the next 60 s. We proposed a method to obtain stochastic differential equations (SDEs) as a mathematical model of the body sway on the basis of the stabilogram. While there are several minimal points of time-averaged potential function in the SDEs, the exposure decreases the gradient of the potential function. We have succeeded in estimating the decrease in the gradient of the potential function by using an index called sparse density.