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Utilizing the advantages of a liquid metal (LM) (i.e., mercury) and its electro‐mechanical properties (i.e., high density, high surface tension, and high electrical conductivity), a novel capacitive‐type two‐axis accelerometer is proposed. The device employs a liquid‐type proof mass (i.e., liquid metal droplet) and is located in a cone‐shaped guiding channel. The Laplace pressure induced by the guiding channel and the LM droplet in the device acts as a spring due to the high surface tension of LM. To accurately set the spring constant of the device, a 2D mathematical model is established. Based on this mathematical model, the influence of the channel shape on device sensitivity is analyzed. Despite measuring the two‐axis accelerations using a single proof mass, the accelerometer yields a cross‐axis sensitivity of less than 1% for the x‐ and y‐axes. The accelerometer demonstrates an output similar to that of a reference accelerometer for a randomly applied acceleration. Owing to the nature of the liquid‐type proof mass, even if it is destroyed, its functionality is recovered by simply shaking the accelerometer. Finally, a 1.4% change in the accelerometer output is observed in the 15 000‐cycle test, and the device is applied to a maze escape game for verification.

Flexible capacitive‐type touch sensors have significant potential in robotics, foldable displays, and wearable electronics. However, the general parallel‐plate structure of these sensors unintentionally changes initial values and sensitivity in various situations, such as in electromagnetic interference (EMI) and bending. In the present study, a double side EMI‐shielded bending‐insensitive capacitive‐type touch sensor is proposed with a linear response over a wide detection range. The device has a novel design that includes double‐sided silver nanowires (AgNWs) embedded on the surface of pyramidal‐polyurethan sponge (AeSoPS) facing the opposite direction. The double‐sided AeSoPS structure offers various advantages, such as bending‐insensitive property, EMI shielding, and linearity and detection range improvement. The fabricated device exhibits excellent linearity (R2 = 0.999) up to 700 kPa, bending‐insensitive property on rigid (up to a radius of curvature of 0.7 mm) and soft surfaces, and accurate pressure measurement with superior EMI shielding effectiveness of 99.9% attenuation from EMI (30 dB within a broad frequency range from 0.5 to 12 GHz). Therefore, the developed sensor with improved performance is promising for use in flexible touch sensors, as it offers reliable sensing functions and EMI protection in various environments.

Dip coating has demonstrated great potential as a multimaterial coating method providing additional functions to substrates or producing a freestanding microscopic layer upon removal of the substrate. In dip coating, a liquid layer is applied on a substrate by dipping and withdrawing it from a liquid bath, and then curing the layer in air. Thus, manufacturing uniformly thick layers on serpentine 3D substrates is difficult due to the influence of gravity during the prolonged curing process, thus hindering the overall potential applications of this method. Herein, a new dip coating method is proposed to overcome the problems of the conventional method by using an immiscible, density‐matched, and interfacial‐tension‐minimized liquid phase, termed the supporting liquid. This new method is performed by dipping and oscillating a serpentine 3D substrate in a biphasic liquid bath with a small amount of prepolymer solution floating atop the supporting liquid. The prepolymer coating, immersed in the supporting liquid, is then cured. The effect of gravity on the prepolymer coating is eliminated by the buoyancy of the supporting liquid and Laplace pressure is weakened by the minimized interfacial tension. This study demonstrates that the new method can fabricate uniformly thick layers covering the entire surface of a serpentine 3D substrate and can be used during the generation of vascular replicas.

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In this paper, a design method to develop a bendinginsensitive capacitive-type touch sensor is reported. To achieve bendinginsensitive properties and a shielding effect to block the parasitic capacitance, the sensor is composed of a silver nanowire-based stretchable top electrode layer, a microstructured dielectric layer, and a film-type bottom electrode layer. The stretchability of the top electrode (i.e., tension or compression according to bending) and the pitch of microstructures, which affect the performance (i.e., initial value and sensitivity) of the sensor in bending situations, are analyzed using mathematical modeling and bending tests based on two perspectives. The analysis is conducted in both bending directions, that is, inward and outward, and the differences in the performance in both directions are analyzed. The fabricated sensor is capable of measuring a wide range of pressures (up to 700 kPa) with a sensitivity of ∼0.14 MPa −1 . The sensor can be successfully applied to soft robotics applications.

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