Blog 2 - HRV

 Blog 2 -  HRV


Heart Rate Variability (HRV) Sensor

The heart rate variability sensor is used to measure a persons heart rate. The sensor shines an LED into a persons finger, which some is absorbed and some is reflected back. The reflected light is read by the photo diode (a semiconductor device with a P-N junction that converts photons (or light) into electrical current). Every time the heart beats, the amount of reflected light changes due to the volume of blood in a person finger tip, which is detected by the by the photo diode.


Block Code


Devices




            Power supply                             Heart rate variability sensor                            Micro:bit


For the setup, I have a micro:bit controller connected to a breadboard / power supply, with the HRV sensor connected to pin 0 of the breadboard

Results

Digital

Analog

 Video



I found this lab very interesting. I would love to extend this further and see if there's a sensor that could measure blood oxygen levels. It was fun to work using a micro:bit for the first time. I can see how there is plenty of learning opportunity and things you can do with a micro:bit.








Comments

Post a Comment

Popular posts from this blog

Blog 2 - HRV Demo

Image
Lab 2 - Simple Heartrate Sensor Demo For the second lab, our task was to explore the capabilities of the Micro-Bit platform by connecting an external sensor to the microcontroller through its' GPIO pins. Readings were aquired through a simple serial read script created in Microsoft Makecode. In this case, the external sensor measures heart rate / pulse by shining a bright green LED light into skin tissue and measuring the light reflected back. As the heart circulates blood around the body, a small variation in pressure occurs within blood vessels, arteries and capillaries. This pressure variation can absorb more or less light at various stages of the heartbeat and is the primary mechanism of the HRV sensor. By detecting fluctuations in light reflected back from the body, it is possible to get an acurate reading on our heartbeat. A similar mechanism of measuring bloodflow is used in other 'smart' technology such as smart watches, fitness bracelets and even in professional me...
Read more

Week 1: HRV Review

Image
  What is it? Heart rate variability (HRV) is the measure of the variation between heartbeats. It is controlled by your autonomic nervous system (ANS). This system operates automatically and regulate process such as the heart rate and other bodily functions that are are not under conscious control. This system is broken into two branches the flight or fight (which preparing the body for action and stress) and the rest + digest (which promotes relaxation + recovery). HRV is influenced by the ability to smoothly shift between these two branches.  High HRV: Larger difference between successive heartbeats - Indicates a more flexible and adaptable autonomic nervous system.  Low HRV: Smaller differences between successive heartbeats - Indicates a less flexible autonomic nervous system.                                                ...
Read more

Blog 5 - FFT & HRV

  Week 7 Project Meeting This week, we discussed a direction we would like to take the HRV sensor in. Using the programs we have created over the past few weeks; the aim is to create a system for monitoring the HRV sensor using the MicroBits.   What is Fast Fourier Transform (FFT) Fast Fourier Transform is an algorithm that helps to identify what frequencies are in a signal. These signals can be anything from audio, communications and biomedical signals. Slower heart rates happen when you're resting or relaxed, and faster rates happen when you're active, stressed or when you’re in danger.   What is HRV https://my.clevelandclinic.org/health/symptoms/21773-heart-rate-variability-hrv Heart Rate Variability is the fluctuation in variability between heartbeats. These variations are very small, adding or subtracting a fraction of a second between beats.   Ethics https://www.geeksforgeeks.org/computer-ethics/
Read more