Pulse Sensor – Heart Rate Detector

Description

1. Working Principle: The sensor typically uses an infrared (IR) or optical method to detect changes in blood volume in the capillaries under the skin, which occur with each heartbeat. These changes in blood volume are used to calculate the heart rate.
2. LED and Photodetector: It usually consists of an IR LED (infrared light-emitting diode) and a photodetector (phototransistor or photodiode) placed on opposite sides of a finger or an earlobe. The LED emits light, and the photodetector measures the light transmitted or reflected through the tissue.
3. Analog Signal: The sensor produces an analog signal that corresponds to the changes in blood volume. This signal is typically in the form of a voltage waveform.
4. Signal Processing: To extract the heart rate information, the analog signal is processed to identify the pulse peaks, and the heart rate is calculated based on the time interval between these peaks.
5. Analog or Digital Output: Some sensors provide analog output, while others may have digital output with heart rate data already processed.
6. Compatible with Arduino and Raspberry Pi: These sensors are compatible with popular development platforms like Arduino and Raspberry Pi, making it easy to interface and process the heart rate data.
7. Connection: They can be connected to these platforms using GPIO pins or analog pins.
8. Power Supply: Typically, they require a supply voltage in the range of 3.3V to 5V.
9. Real-Time Monitoring: They enable real-time monitoring of heart rate and can be used for various applications, including fitness trackers, heart rate monitors, and biofeedback systems.
10. Applications: In addition to health and fitness applications, they can be used in medical devices, sports equipment, and even as part of DIY smart wearable projects.