The PIC16F628A based heart rate meter is one of the most popular projects published on Embedded Lab. In this article, I am going to show how to replicate the same project using a simpler platform like Arduino. The Arduino heart rate meter will use Arduino Uno, Easy Pulse Plugin, and 4-digit SPI seven segment LED display module. It computes the heart beat rate by processing the analog pulse signal output from the Easy Pulse Plugin sensor and displays it on the seven segment display module. The heart beat rate is refreshed every ~3 sec.
Tag Archives: pulse sensor
Today we are happy to announce the release of a new addition to our Easy Pulse Sensor series named Easy Pulse Plugin. Like its predecessors, the original Easy Pulse and Easy Pulse V1.1, Easy Pulse Plugin also operates on the principle of Photoplethysmography, which is an optical technique of sensing blood volume changes in tissues by illuminating the skin surface with a light source and measuring the reflected or transmitted light using a photodetector. The photodetector output contains the cardiovascular pulse wave, which is synchronized with the beating of the heart. Easy Pulse Plugin provides all necessary instrumentation and amplification on board to detect the cardiovascular pulse signal from the fingertip. The most important characteristics of Easy Pulse Plugin is that it can be easily plugged into the left headers of Arduino Uno (or its compatible clone) board for easy interfacing, and the analog pulse signal can be fed to either A0 or A1 analog input through a 2-pin jumper selection. You can buy this sensor at our Tindie Store as well as from Elecrow with worldwide shipping.
The heart rate, also referred to as pulse rate, has been recognized as a vital sign since the beginning of medicine, and it is directly related to a person’s cadiovascular health. Today, we are going to make a PC-based heart rate monitor system using an Arduino board and Easy Pulse V1.1 sensor. Easy Pulse is a pulse detecting sensor that uses the principle of transmission photo-plethysmography (PPG) to sense the pulse signal from a finger tip. The sensor output is read by the Arduino board, which then transfers the data to the PC through a serial interface. A PC application is developed using Processing programming language to display the received PPG signal and instantaneous heart rate.
The Easy Pulse sensor is designed for hobby and educational applications to illustrate the principle of photoplethysmography (PPG) as a non-invasive optical technique for detecting cardio-vascular pulse wave from a fingertip. It uses an infrared light source to illuminate the finger on one side, and a photodetector placed on the other side measures the small variations in the transmitted light intensity. The variations in the photodetector signal are related to changes in blood volume inside the tissue. The signal is filtered and amplified to obtain a nice and clean PPG waveform, which is synchronous with the heart beat. The original version of Easy Pulse uses the TCRT1000 reflective optical sensor to sense the blood variation in the finger tissue and outputs a digital pulse which is synchronous with the heart beat. Today, we are pleased to announce the release of Easy Pulse Version 1.1, which has some improvements over the original design. The new version provides both analog PPG waveform as well as digital pulse signal as separate outputs. Easy Pulse Version 1.1 board is available for purchase on Tindie. Recently, our Chinese distributor Elecrow has also started selling it for $18.50, and they can ship it world-wide at lower cost.
Sergej Stoetzer and two of his students just finished their virtual jogging project, where the Easy Pulse board has been used to provide a biofeedback to their system. They interfaced an ear-clip sensor to the Easy Pulse board to detect the heart beat during virtual jogging. The output of the Easy Pulse board goes to a Lego Mindstorms NXT-Brick, which in turn hits the Arrow Up key on a keyboard connected to PC. On the PC, a Google Street view is opened which moves forward every time the Arrow Up key is hit. So, the idea is to give you a virtual scenic run while jogging on a treadmill. The Easy Pulse detects the heart beat and the Lego Mindstorms NXT hits the Arrow Up key after every 4th pulse. More you jog, faster would be your pulse rate, and the scene changes on the PC screen accordingly.
It was a very interesting project. Thanks to Sergej for informing us about this.