Jo Jeyeon, Park Heeju T
Department of Textiles, Merchandising, and Interiors, University of Georgia, Athens, GA, USA.
Department of Human Centered Design, Cornell University, Ithaca, NY, USA.
Wearable Technol. 2025 Feb 17;6:e7. doi: 10.1017/wtc.2024.26. eCollection 2025.
Real-time measurement of head rotation, a primary human body movement, offers potential advantages in rehabilitating head or neck motor disorders, promoting seamless human-robot interaction, and tracking the lateral glance of children with autism spectrum disorder for effective intervention. However, existing options such as cameras capturing the entire face or skin-attached sensors have limitations concerning privacy, safety, and/or usability. This research introduces a novel method that employs a battery-free RFID tag-based wearable sensor for monitoring head orientation, as a substitute for the existing options like camera. By attaching a pair of passive RFID tags to the front of the head at a specific distance from each other, the signal strength of each tag within the pair differs based on the discrepancy in distance from the RFID reader caused by head rotation. Important parameters including distance between the tags, distance from the reader, and tag types, are investigated to suggest optimal sensor design. In tests involving random head rotations by 10 healthy adults, there was a significant correlation between the orientation of the head and gaze in the yaw direction and the differences in signal strength from the sensor pairs. The correlation coefficients () were satisfactory, at 0.88 for head and 0.83 for left eye pupil orientations. However, the sensor failed to estimate pitch rotations for head and gaze, due to the insufficient vertical spacing between the tags. No demographic factors appeared to influence the results.
实时测量头部旋转这一主要人体运动，在恢复头部或颈部运动障碍、促进人机无缝交互以及追踪自闭症谱系障碍儿童的侧视以进行有效干预方面具有潜在优势。然而，现有的方法，如捕捉整个面部的摄像头或附着在皮肤上的传感器，在隐私、安全和/或可用性方面存在局限性。本研究引入了一种新颖的方法，即采用基于无源射频识别（RFID）标签的无电池可穿戴传感器来监测头部方向，以替代像摄像头这样的现有设备。通过将一对无源RFID标签以特定距离附着在头部前方，由于头部旋转导致的与RFID阅读器距离差异，该对标签中每个标签的信号强度会有所不同。研究了包括标签之间的距离、与阅读器的距离以及标签类型等重要参数，以提出最佳的传感器设计。在涉及10名健康成年人随机头部旋转的测试中，头部和注视在偏航方向的方向与传感器对信号强度差异之间存在显著相关性。相关系数（）令人满意，头部为0.88，左眼瞳孔方向为0.83。然而，由于标签之间的垂直间距不足，该传感器无法估计头部和注视的俯仰旋转。没有人口统计学因素似乎会影响结果。
