An Empirical Study of Virtual Reality Sickness based on Self-motion Perception

在最近的虚拟现实（VR）系统中，在诸如医学、康复和教育的许多领域中已经期望各种实际应用。因此，需要充分考虑人的因素，以构建安全舒适的虚拟现实系统。然而，很少有一个VR系统，充分考虑到人的因素，实际上。需要一个安全的虚拟现实系统的指导方针，以防止人类的不良反应，如晕动病。因此，我们开展了一项研究项目，如何预防或减少虚拟环境中的VR疾病。首先，我们开发了一个集成的VR刺激系统，可以同时控制和显示视觉，听觉和前庭刺激，然后是人体反应的监测系统。其次，使用这些系统，我们研究了视觉诱导的自我运动知觉（vection）是否可能与VR疾病有关，是否可以通过不同类型的感官刺激（如听觉或前庭刺激）进行控制。从我们的实验结果可以确定，声音和前庭刺激是有效的，以减少向量。此外，我们研究了在混合现实下，使用视频透视MHD的真实的和虚拟的字之间的时间和空间的差距对人体的影响。从我们的实验结果中，可以确定，在使用3D-HMD的操作效率优于2D-HMD，虽然效率强烈依赖于时间延迟。除了上述研究之外的副作用结果是1）长时间使用HMD对人类视觉系统的影响，2）从宽视野HMD产生的视动刺激对站立平衡的影响，3）注视目标对扭转视动性眼球震颤的影响，4）与老年人的福尔斯有关的视觉系统，以及5）开发使用透视HMD和自动语音识别系统两者的助听器系统。

In recent Virtual Reality (VR) systems, various practical applications have been expected in many fields such as medicine, rehabilitation and education. Therefore, enough considerationn of human factors are needed to construct the safe and comfortable VR systems. However, there is seldom a VR system that sufficiently considered the human factors actually. A guideline for the safe VR systems to prevent human from undesirable reactions such as motion sickness is desired. So we carried out a research project how to prevent or reduce VR sickness in virtual environments. First, we developed an integrated VR stimulation system that could control and display visual, acoustic and vestibular stimuli simultaneously, and then a monitoring system of human body reactions. Secondly, using these systems, we examined whether visually induced self-motion perception (vection) that was possible to relate the VR sickness could control or not by a different kind of sensory stimulation such as an acoustic or vestibular stimulus. From our experimental results, it was ascertained that the acoustic and vestibular stimulus was effective to reduce the vection. In addition, we examined influence on human body concerning temporal and spatial gaps between a real and a virtual word under Mixed Reality using a video see-through MHD. From our experimental results, it was ascertained that manipulation efficiency in using a 3D-HMD was better than a 2D-HMD although the efficiency strongly depended on time delay. Side results except the above-mentioned studies were 1) influence on human visual system by using a HMD for a long time, 2) effects of optokinetic stimulations produced from a wide view HMD on standing balance, 3) effects of a fixation target on torsional optokinetic nystagmus, 4) visual system associated with falls in the elderly, and 5) development of a hearing aid system using both a see-through HMD and an automatic speech recognition system.