A wireless on-skin inertial sensor based on free-moving liquid metal is introduced. The inertial sensor comprises a eutectic gallium–indium (eGaIn) droplet that modulates the capacitance between two electrodes. The capacitive output of the sensor is connected to a planar coil to form an LC resonator whose resonant frequency can be read out wirelessly. Liquid metal electrodes and the coil are fabricated on a 20 μm thick silicone membrane, which can stretch up to 600%, using spray-deposition of eGaIn. The moving droplet is encapsulated on the opposite side of the membrane using spray-deposition of Dragon Skin 10 silicone. The output characteristics, electrical simulations of the capacitance, and dynamic characteristics of the sensor are shown. The sensor is used for measuring tilt angles and recording arm gestures.

中文翻译：

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皮肤上液态金属惯性传感器

介绍了一种基于液态金属自由移动的无线皮肤惯性传感器。惯性传感器包括一个共晶的镓铟铟（eGaIn）小滴，可调节两个电极之间的电容。传感器的电容性输出连接到平面线圈以形成LC谐振器，其谐振频率可以无线读取。液态金属电极和线圈是在厚度为20μm的硅膜上制造的，该膜可通过eGaIn的喷涂沉积而拉伸至600％。使用Dragon Skin 10有机硅的喷涂将移动的液滴封装在膜的另一侧。显示了输出特性，电容的电仿真和传感器的动态特性。该传感器用于测量倾斜角度并记录手臂手势。