HeadTurner: 透過輔助肩部與頭部驅動提升虛擬與混合實境頭戴式裝置在躺臥時的視野範圍與舒適度

Abstract

Apple Vision Pro 與 Meta Quest 等虛擬與混合實境頭戴式顯示器，自 2024 年起開始支援仰躺姿勢的使用模式，以因應偏好或需要此種姿勢的使用者。然而，使用者所倚靠的平面會限制肩膀與頭部的旋轉，進而降低視野範圍與舒適度。為了確認這項議題的存在性與量化其重要性，我們進行了一項形成性研究（n=16），比較站立與仰躺姿勢下的頭戴顯示器使用情況，結果顯示頭部的水平旋轉範圍從 261º 降至 130º，垂直方向則從 172º 降至 94.9º。為了改善此問題，我們進行了一系列迭代測試並提出 HeadTurner，一種動態輔助使用者轉頭的創新方法，透過驅動承托使用者後背的平面與頭枕，藉由在水平旋轉上的讓位行為與抬頭低頭時的貼合跟追，模擬人類在站立姿勢下上半身的自由旋轉，以此提升視野與舒適度。在總結性使用者研究（n=16）中，我們評估了這樣的方法在偏靜態與動態的商業應用中的有效性，發現 HeadTurner 相較於固定的平面顯著擴展了可視範圍並提升了使用舒適度；另外雖然使用者的暈眩感也有略微降低，但統計上未達顯著差異。整體而言，75% 的受試者偏好使用 HeadTurner。我們目前的概念性原型是以床為實作情境，但此方法可延伸應用至更輕巧且常見的智能家居設備上，如電動可調式座椅，這也是我們預期最能展現長時間躺臥使用頭戴式裝置價值的未來。

Virtual and mixed reality headsets, such as the Apple Vision Pro and Meta Quest, began supporting use in reclined postures in 2024, accommodating users who prefer or require this position. However, the surfaces on which users rest restrict shoulder and head rotation, reducing viewing range and comfort. A formative study (n=16) comparing usage while standing vs. lying down showed that head rotation range decreased from 261º to 130º horizontally and from 172º to 94.9º vertically. To improve viewing range and comfort, we present HeadTurner, a novel approach that assists user-initiated head rotations by actuating the resting surface to yield in pitch and yaw axes. In a user study (n=16), HeadTurner significantly expanded the field of view and improved comfort compared to a fixed surface. Although VR sickness was slightly reduced with HeadTurner, the difference was not statistically significant. Overall, HeadTurner was preferred by 75% of participants. Although our proof-of-concept device was prototyped as a bed, the approach can be extended to more compact and affordable device form factors, such as motorized reclining chairs, offering the potential for comfortable use of VR and MR headsets over extended periods, and was shown to inspire users with interested applications in back-rested scenarios.