Respiratory rate monitoring system based on inorganic halide perovskite humidity sensor
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摘要: 呼吸率检测中存在主观因素强、信号提取复杂、设备不易获取和有线连接不方便测试者移动等问题。人体呼吸周期为3 s~6 s,呼吸气流是呼吸动作的最直接反应,与周围空气存在湿度差。本文采用研制的新型无机卤化物钙钛矿湿度传感器测量呼吸率,克服了市面上湿度传感器响应和恢复时间长(10 s以上)的问题。系统使用Zigbee无线通信传输检测信号,使信号检测和处理部分分离,方便测试者移动。使用上位机软件进行数据处理计算呼吸率,并根据呼吸暂停阈值判断呼吸状态。测试结果表明,系统可实时准确监测呼吸率,最大误差1次/分钟,具有准确率高、信号处理简单、便携和成本低的优势。Abstract: The traditional respiratory rate measurement technologies have several deficiencies, such as subjective appraised results, complicated signal extraction processes, difficult access to equipment, and inconvenience to move due to the wired connection setting. The respiratory airflow can directly reflect the human breath, and the respiratory frequency is usually 10~12 breaths/min (1 ventilation every 5~6 seconds). The humidity difference between exhalation and inhalation can be directly used to measure respiratory rate. In the present work, a wireless respiratory rate monitoring system based on inorganic halide perovskite humidity sensor was developed. The sensor exhibits an ultrasensitive humidity sensing performance, which overcomes the long response/recovery time (> 10 seconds) of the commercial humidity sensors. The system utilized a Zigbee wireless communication to transmit the measurement signal, which separates the signal detection and processing parts, making it easier for the tester to move. The upper computer software was designed and used for data processing to calculate the breathing rate. The system can accurately monitor the respiratory rate in real-time, recognize and alarm the apnea successfully by comparing with a setting threshold value. The test results show that the system can accurately monitor the breathing rate with a maximum error of 1 time per minute. The system possesses great potential for application in respiratory rate monitoring due to its high accuracy, simple operation, portability, and low cost.
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表 1 呼吸率测试
Table 1. Respiratory rate testing
编号 呼吸率(次/分钟) 慢速 正常 快速 实际 测试 实际 测试 实际 测试 测试者1 7 6 17 17 28 28 测试者2 8 8 15 14 24 25 测试者3 11 11 18 18 26 26 测试者4 9 9 16 15 25 24 测试者5 8 7 16 16 24 24 -
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