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Abstract High spatial‐resolution detection is essential for biomedical applications and human‐machine interaction. However, as the sensor array density increases, the miniaturization will lead to interference between adjacent units and deterioration in sensing performance. Here, inspired by the cochlea's sensing structure, a high‐density flexible pressure sensor array featuring with suspended sensing membrane with sensitivity‐enhanced customized channels is presented for crosstalk‐free and high‐resolution detection. By imitating the basilar membrane attached to spiral ligaments, a sensing membrane is fixed onto a high‐stiffness substrate with cavities, forming a stable braced isolation to provide an excellent crosstalk‐free capability (crosstalk coefficient: 47.24 dB) with high‐density integration (100 units within 1 cm2). Similar to the opening of ion channels in hair cells, the wedge‐type expansion of the embedded cracks introduced by stress concentration structures enables a high sensitivity (0.19 kPa−1) and a large measuring range (400 kPa). Finally, it demonstrates promising applications in distributed displays and the condition monitoring of medical‐surgical intubation.

Micro rotary structures have attracted increasing attention in many industrial applications. However, the fabrication of complex micro rotary structures with high strength, high hardness, and low rigidity, poses a significant challenge to traditional machining methods. To solve this difficult problem, this study proposes a novel method of fabricating complex micro rotary structures by using wire electrochemical grinding (WECG), which is an anodic dissolution process and has no machining force. WECG, a type of ECM, has some major advantages over wire electrical discharge grinding (WEDG): no electrode wear, absence of residual stress, good surface quality, low machining cost, and high machining efficiency. Firstly, this study investigated the influences of the process parameters on the dimensional accuracy of the micro grooves produced, then optimized these process parameters. A qualitative simulation of WECG was conducted to reveal the reason for the trumpet-like micro grooves fabricated by WECG. Finally, based on the optimal process parameters, several different kinds of rotary structures were successfully produced by WECG. The experimental results demonstrate that WECG is a promising method for fabricating complex rotary structures of difficult-to-cut materials at low cost and with high efficiency.

The instability of machining process caused by the difficulty of the electrolyte refresh in electrochemical micromachining (EMM) of micro through-hole has been an unsolved problem. Thus, this paper investigates the electrochemical micromachining of micro through-hole by using a micro helical electrode combining with the jetting electrolyte. With the help of high-speed rotation of micro helical electrode and its spiral shape, the internal electrolyte can be stirred while the external jetting electrolyte can flow into the hole along the spiral groove to refresh the electrolyte effectively, thereby, improving the machining stability of EMM. Firstly, the influence of the process parameters on the fabrication of micro through-hole in the EMM by using micro helical electrode without non-conductive mask is investigated. Based on the optimization of the process parameters, a micro through-hole with an inlet dimension of 121.6 μm and an outlet dimension of 114.9 μm is obtained successfully. Furthermore, this paper also tries to use the micro helical electrode coated with the non-conductive mask to decrease the bad influence of the stray corrosion attack. It is found that the non-conductive mask coated on the surface of micro helical electrode can improve the machining accuracy significantly under the condition of low pulse frequency (≤1 KHz). However, its good effect on preventing the stray corrosion decreases along with the increase of the pulse frequency.