Electronic stethoscope used to detect cardiac sounds that contains essential clinical information is a primary tool for diagnosis of various cardiac disorders. However, the linear electro‐mechanical constitutive relation makes conventional piezoelectric sensors rather ineffective to detect low‐intensity, low‐frequency heart acoustic signal without the assistance of complex filtering and amplification circuits. Herein, we find that triboelectric sensor features superior advantages over piezoelectric one for micro‐quantity sensing originated from the fast saturated constitutive characteristic. As a result, the triboelectric sensor shows ultrahigh sensitivity (1215 mV/Pa) than the piezoelectric counterpart (21 mV/Pa) in the sound pressure range of 50 – 80 dB under the same testing condition. By designing a trumpet‐shaped auscultatory cavity with a power function cross‐section to achieve acoustic energy converging and impedance matching, triboelectric stethoscope delivers 36 dB signal‐to‐noise ratio for human test (2.3 times of that for piezoelectric one). Further combining with machine learning, five cardiac states can be diagnosed at 97% accuracy. In general, the triboelectric sensor is distinctly unique in basic mechanism, provides a novel design concept for sensing micromechanical quantities, and presents significant potential for application in cardiac sounds sensing and disease diagnosis.This article is protected by copyright. All rights reserved

中文翻译：

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用于超灵敏心音传感和疾病诊断的声学增强摩擦电听诊器


用于检测包含重要临床信息的心音的电子听诊器是诊断各种心脏疾病的主要工具。然而，线性机电本构关系使得传统压电传感器在没有复杂的滤波和放大电路的帮助下检测低强度、低频心声信号相当无效。在这里，我们发现摩擦电传感器由于其快速饱和本构特性而在微量传感方面比压电传感器具有优越的优势。因此，在相同的测试条件下，摩擦电传感器在 50 – 80 dB 的声压范围内表现出比压电传感器 (21 mV/Pa) 更高的灵敏度 (1215 mV/Pa)。通过设计具有幂函数截面的喇叭形听诊腔，实现声能汇聚和阻抗匹配，摩擦电听诊器可为人体测试提供36 dB的信噪比（是压电听诊器的2.3倍）。进一步结合机器学习，可以诊断五种心脏状态，准确率高达 97%。总的来说，摩擦电传感器在基本机制上具有明显的独特性，为传感微机械量提供了新颖的设计理念，在心音传感和疾病诊断方面具有巨大的应用潜力。本文受版权保护。版权所有