Stretchable electronics have the fundamental advantage of matching the complex geometries of the human body, providing opportunities for real-time biomechanical sensing. We report a method for high-frequency AC-enhanced resistive sensing that leverages deformable liquid metals to improve low-power detection of mechanical stimuli in wearable electronics. The fundamental mechanism of this enhancement is geometrical modulation of the skin effect, which induces current crowding at the surface of a liquid metal trace. In combination with DC sensing, this method quantitatively pinpoints mechanical modes of deformation such as stretching in-plane and compression out-of-plane that are traditionally impossible to distinguish. Here we explore this method by finite element simulations then employ it in a glove to detect hand gestures and tactile forces as well as a respiratory sensor to measure breathing. Moreover, this AC sensor uses lower power (100X) than DC sensors, enabling a new generation of energy-efficient wearables for haptics and biomedical sensing.

可拉伸电子产品具有匹配人体复杂几何形状的基本优势，为实时生物力学传感提供了机会。我们报告了一种高频交流增强电阻传感方法，该方法利用可变形液态金属来改善可穿戴电子设备中机械刺激的低功率检测。这种增强的基本机制是趋肤效应的几何调制，它会在液态金属迹线的表面引起电流拥挤。结合直流传感，该方法可以定量地确定变形的机械模式，例如平面内拉伸和平面外压缩，这些模式传统上是无法区分的。在这里，我们通过有限元模拟探索这种方法，然后在手套中使用它来检测手势和触觉力以及呼吸传感器来测量呼吸。此外，这种交流传感器比直流传感器使用更低的功率（100 倍），从而为触觉和生物医学传感提供新一代的节能可穿戴设备。