fig1

Figure 1. From surface sensing to subsurface intelligence for wearable hand tracking. Conventional methods infer hand motion from surface-level electrical or kinematic proxies (left), while contemporary subsurface sensing directly images deep tissue dynamics (center). This progression drives real-time reconstruction of continuous 22-DOF hand kinematics for VR control, rehabilitation, and teleoperation (right). DOF: Degree of freedom; VR: virtual reality; EMG: electromyography; AR: augmented reality.