Abstract: The cybersickness is still a huge obstacle for virtual reality (VR) system. Current researches on cybersickness are mostly based on static or dynamic simulators, while studies in the real movement state is rare. An evaluating system which employed a head-mounted display (HMD) with a running vehicle was proposed to study the cybersickness in the real movement state. In this system, users sitting in the vehicle could see virtual scenes which was consistent with the real motion through the HMD. Subjective and objective evaluating experiments were proposed to analyze the different levels of the cybersickness caused by visual-vestibular conflict. The results show that the consistency of real movement and visually perceived movement have a great impact on cybersickness. Cybersickness gets worse when the consistency decreases. Serious cybersickness may lead to extreme situation where the discomfort may not be afforded by users.

Key words: cybersickness, real movement, visual-vestibular conflict, head-mounted display