Piezoelectric Micromachined Ultrasonic Transducer Array-Based Electronic Stethoscope for Internet of Medical Things

A piezoelectric micromachined ultrasonic transducer (PMUT) array-based smart electronic stethoscope is presented for Internet of Medical Things (IoMT). For the first time, an electronic stethoscope based on a high-performance PMUT array is demonstrated to record mechanoacoustic cardiopulmonary signals from the body. This electronic stethoscope can continuously capture the cardiopulmonary signals and enable the telemedicine as well as the digital smart medical becoming a reality. The measured cardiopulmonary signals are collected using the PMUT array and transmitted to a mobile terminal via Bluetooth. Then, primary diagnosis can be implemented in real time using a customized APP in the terminal. The PMUT array was designed with high acoustic pressure sensitivity, high noise resolution, and wide operation bandwidth. These crucial parameters enabled simultaneous monitoring of multiple health parameters associated with the cardiopulmonary system, namely, respiratory rate, heart rate, lung sounds, and heart sounds. A feasibility test was implemented on patients with preexisting medical condition, in order to detect weak mechanoacoustic signals related to tachyarrhythmia and asthma. This article demonstrates the potential use of smart electronic stethoscope in healthcare applications, such as the assessment of heart and lung diseases, which provides an innovative auscultation technology and brings great benefits to IoMT.