Passengers of level 3-5 autonomous personal mobility vehicles (APMV) can perform non-driving tasks, such as reading books and smartphones, while driving. It has been pointed out that such activities may increase motion sickness, especially when frequently avoiding pedestrians or obstacles in shared spaces. Many studies have been conducted to build countermeasures, of which various computational motion sickness models have been developed. Among them, models based on subjective vertical conflict (SVC) theory, which describes vertical changes in direction sensed by human sensory organs v.s. those expected by the central nervous system, have been actively developed. However, no current computational model can integrate visual vertical information with vestibular sensations. We proposed a 6 DoF SVC-VV model which added a visually perceived vertical block into a conventional 6 DoF SVC model to predict visual vertical directions from image data simulating the visual input of a human. In a driving experiment, 27 participants experienced an APMV with two visual conditions: looking ahead (LAD) and working with a tablet device (WAD). We verified that passengers got motion sickness while riding the APMV, and the symptom were severer when especially working on it, by simulating the frequent pedestrian avoidance scenarios of the APMV in the experiment. In addition, the results of the experiment demonstrated that the proposed 6 DoF SVC-VV model could describe the increased motion sickness experienced when the visual vertical and gravitational acceleration directions were different.

翻译：Level 3-5自主个人移动车辆（APMV）的乘客在驾驶过程中可以执行非驾驶任务，例如阅读书籍和使用智能手机。已有研究表明，此类活动可能加剧晕动症，尤其是在共享空间中频繁避让行人或障碍物时。为建立应对措施，多项研究已展开，并开发了多种计算性晕动症模型。其中，基于主体垂直冲突（SVC）理论的模型得到了积极发展，该理论描述了人体感官感知的垂向方向变化与中枢神经系统预期方向之间的差异。然而，目前尚无计算模型能将视觉垂直线信息与前庭感觉进行整合。我们提出了一种六自由度SVC-VV模型，该模型在传统六自由度SVC模型中增加了视觉感知垂直线模块，通过模拟人类视觉输入的图像数据预测视觉垂直线方向。在一项驾驶实验中，27名参与者体验了APMV的两种视觉条件：向前看（LAD）和使用平板设备工作（WAD）。通过模拟APMV在实验中频繁避让行人的场景，我们验证了乘客在乘坐APMV时会出现晕动症，尤其是在执行任务时症状更为严重。此外，实验结果证明，所提出的六自由度SVC-VV模型能够描述当视觉垂直线方向与重力加速度方向不一致时晕动症加剧的现象。