基于可穿戴光电容积脉搏波的母鸡心率测量方法

Heart Rate Measurement Method for Hens Based on Wearable Photoplethysmography

摘要:

心率是母鸡的重要生理指标, 但目前对鸡心率的测量往往是侵入性的。 光电容积脉搏波 (Photoplethysmography,PPG)技术是一种低成本、可穿戴的非侵入式心率检测技术。 本文设计了一种基于光电容积脉搏波技术的可穿戴心率检测装置,用于从母鸡胸部裸区测量心率信号。 并在对母鸡束缚与非束缚状态下进行了心率穿戴测量实验。 采用巴特沃斯(Butterworth)无限脉冲响应(Infinite impulse response,IIR)带通滤波器对 PPG 信号进行滤波,以去除低频漂移和高频噪声。 随后,通过快速傅里叶变换分析其频谱特征,并提取主要频率分量以估算心率。 之后以心电图(Electrocardiogram,ECG)信号作为标准评估 PPG 信号的质量,在束缚状态下,皮尔逊相关系数达到 0. 983 3, 平均绝对误差(Absolute error, MAE)为 1. 970 2 B / min, 均方根误差(Mean square error, RMSE)为 2. 533 8 B / min;在非束缚状态下,皮尔逊相关系数为 0. 978 4,计算所得平均绝对误差为 5. 196 0 B / min, 均方根误差 7. 232 9 B / min。 实验结果表明,基于 PPG 技术的心率测量与 ECG 技术具有高度一致性,验证了 PPG 技术在母鸡心率检测中的可行性与可靠性。

Abstract:

Heart rate is an important physiological indicator for hens, yet current methods for measuring chicken heart rate are often invasive. Photoplethysmography (PPG)is a low-cost, wearable, and non- invasive technique for heart rate detection. A wearable device based on PPG technology was designed to measure heart rate signals from the bare chest area of hens. Experiments were conducted to monitor heart rate under both restrained and unrestrained conditions. A Butterworth infinite impulse response (IIR)bandpass filter was used to process the PPG signals, removing low-frequency drift and high-frequency noise. The filtered signals were then analyzed by using fast Fourier transform to extract spectral characteristics and estimate the dominant frequency component corresponding to heart rate. The quality of the PPG signal was evaluated by using ECG as the reference standard. Under restrained conditions, the Pearson correlation coefficient reached 0. 983 3, with a mean absolute error (MAE)of 1. 970 2 B / min and a root mean square error (RMSE)of 2. 533 8 B / min. Under unrestrained conditions, the Pearson correlation coefficient was 0. 978 4, the MAE was 5. 196 0 B / min, and the RMSE was 7. 232 9 B / min. The experimental results demonstrated a high degree of agreement between PPG-based heart rate measurements and electrocardiogram (ECG)readings, confirming the feasibility and reliability of using PPG technology for monitoring heart rate in hens. The research result highlighted the potential of non- invasive heart rate monitoring in poultry by using PPG-based techniques.