Department of Materials, School of Natural Sciences, The University of Manchester, Manchester M13 9PL, U.K.
Computer and Informatics Engineering, Istanbul Technical University, Istanbul 34469, Turkey.
ACS Sens. 2022 Aug 26;7(8):2281-2292. doi: 10.1021/acssensors.2c00824. Epub 2022 Jul 22.
Despite the importance of respiration and metabolism measurement in daily life, they are not widely available to ordinary people because of sophisticated and expensive equipment. Here, we first report a straightforward and economical approach to monitoring respiratory function and metabolic rate using a wearable piezoelectric airflow transducer (WPAT). A self-shielded bend sensor is designed by sticking two uniaxially drawn piezoelectric poly l-lactic acid films with different cutting angles, and then the bend sensor is mounted on one end of a plastic tube to engineer the WPAT. The airflow sensing principle of the WPAT is theoretically determined through finite element simulation, and the WPAT is calibrated with a pulse calibration method. We prove that the WPAT has similar accuracy (correlation coefficient >0.99) to a pneumotachometer in respiratory flow and lung volume assessment. We demonstrate metabolism measurement using the WPAT and the relationship between minute volume and metabolic rates via human wear trials. The mean difference of measured metabolic rates between the WPAT and a Biopac indirect calorimeter is 0.015 kcal/min, which shows comparable performance. Significantly, unlike the Biopac indirect calorimeter with an airflow sensor, an oxygen gas sensor, and a carbon dioxide gas sensor, we merely use the simple-structured WPAT to measure metabolism. Thus, we expect the WPAT technology to provide a precise, convenient, and cost-effective respiratory and metabolic monitoring solution for next-generation medical home care applications and wearable healthcare systems.
尽管呼吸和代谢测量在日常生活中非常重要，但由于设备复杂且昂贵，普通民众无法广泛获得这些测量。在这里，我们首次报道了一种使用可穿戴式压电气流换能器（WPAT）监测呼吸功能和代谢率的简单经济方法。通过将两个具有不同切割角度的单轴拉伸聚 L-乳酸薄膜粘贴在一起，设计了自屏蔽弯曲传感器，然后将弯曲传感器安装在塑料管的一端，以设计 WPAT。通过有限元模拟理论确定 WPAT 的气流感测原理，并使用脉冲校准方法对 WPAT 进行校准。我们证明 WPAT 在呼吸气流和肺量评估方面与气动流量计具有相似的准确性（相关系数>0.99）。我们通过人体佩戴试验证明了 WPAT 可用于代谢测量，以及分钟通气量与代谢率之间的关系。WPAT 和 Biopac 间接热量计测量代谢率的平均差异为 0.015 kcal/min，表明性能相当。值得注意的是，与具有气流传感器、氧气传感器和二氧化碳传感器的 Biopac 间接热量计不同，我们仅使用结构简单的 WPAT 来测量代谢率。因此，我们期望 WPAT 技术为下一代医疗家庭护理应用和可穿戴医疗保健系统提供精确、方便且具有成本效益的呼吸和代谢监测解决方案。
