A filtered analog voltage (0–5V) that mimics an ECG signal. Add a 0.1µF capacitor between output and GND to smooth PWM ripple. Part 3: Software Heartbeat Simulator (Python for Testing) For testing heart rate algorithms or generating synthetic data, use Python with numpy and matplotlib . Python Code: import numpy as np import matplotlib.pyplot as plt def generate_ecg(sample_rate=500, duration=10, bpm=75): t = np.linspace(0, duration, int(sample_rate*duration)) ecg = np.zeros_like(t)
# T wave def t_wave(t_center, t): return 0.35 * np.exp(-((t - t_center)**2) / (0.1)) heartbeat simulator
beat_interval = 60 / bpm for i in range(int(duration / beat_interval)): center = i * beat_interval + 0.2 # offset to place QRS ecg += qrs(center, t) ecg += p_wave(center - 0.15, t) ecg += t_wave(center + 0.3, t) A filtered analog voltage (0–5V) that mimics an ECG signal