We present Ring-a-Pose, a single untethered ring that tracks continuous 3D hand poses. Located in the center of the hand, the ring emits an inaudible acoustic signal that each hand pose reflects differently. Ring-a-Pose imposes minimal obtrusions on the hand, unlike multi-ring or glove systems. It is not affected by the choice of clothing that may cover wrist-worn systems. In a series of three user studies with a total of 30 participants, we evaluate Ring-a-Pose's performance on pose tracking and micro-finger gesture recognition. Without collecting any training data from a user, Ring-a-Pose tracks continuous hand poses with a joint error of 14.1mm. The joint error decreases to 10.3mm for fine-tuned user-dependent models. Ring-a-Pose recognizes 7-class micro-gestures with a 90.60% and 99.27% accuracy for user-independent and user-dependent models, respectively. Furthermore, the ring exhibits promising performance when worn on any finger. Ring-a-Pose enables the future of smart rings to track and recognize hand poses using relatively low-power acoustic sensing.

翻译：本文提出Ring-a-Pose，一种能够追踪连续三维手部姿态的独立无束缚指环。该指环位于手掌中心，发射人耳听不见的声学信号，不同手部姿态会对信号产生不同的反射。与多指环或手套系统相比，Ring-a-Pose对手部的干扰极小。它不受可能遮挡腕戴系统的衣物选择的影响。通过三项共计30名参与者参与的用户研究，我们评估了Ring-a-Pose在姿态追踪和微手指手势识别方面的性能。在未收集用户任何训练数据的情况下，Ring-a-Pose追踪连续手部姿态的关节误差为14.1毫米。对于经过微调的用户依赖模型，关节误差可降低至10.3毫米。在识别7类微手势任务中，用户无关模型和用户依赖模型的准确率分别为90.60%和99.27%。此外，该指环佩戴在任何手指上均表现出良好的性能。Ring-a-Pose为未来智能指环利用相对低功耗的声学传感实现手部姿态追踪与识别提供了可能。