Recording ECG Signals Using Heart BioAmp Candy

In this project we will be recording ECG using Heart BioAmp Candy.

What is Electrocardiography (ECG)?

Electrocardiography is the measurement of electrical activity in the heart.

About Heart BioAmp Candy:

Heart BioAmp Candy is a candy-sized sensor for recording ECG signals easily. It is perfect for students and researchers as it offers reliable and accurate ECG recordings, making heart monitoring accessible and convenient for educational and research purposes.

The entire BioAmp Hardware series of sensors from Upside Down Labs is designed in a way to teach you the basics of the instrumentation amplifier, active bandpass filtering, soldering, programming, neuroscience, HCI, and BCI just to name a few concepts.

HARDWARE:

1 x Heart BioAmp Candy Kit which contains the following (Upside Down Labs Store | Tindie Store)

1. 1 x Heart BioAmp Candy
2. 1 x BioAmp Cable v3 (100cm)
3. 12 x Gel Electrodes
4. 3 x Jumper Cables
5. 1 x Heart BioAmp Candy

1 x Arduino Uno R4 (You can use any other 3.3V or 5V microcontroller development board with an ADC as well but we chose Arduino Uno R4 as it is compatible with CHORDS and has an ADC of 14 bits so the quality of the signal acquisition will be very good)

1 x Nuprep Skin Preparation Gel

1 x Wet wipe

1 x Electrode Gel (only if using Heart BioAmp Band)

1 x Laptop (It is must to use a laptop and not a desktop (PC) as using a desktop will cause lot of 50/60Hz interference noise in the signals)

SOFTWARE:

Arduino IDE

CHORDS

Connect Heart BioAmp Candy to Arduino Uno R4 using the jumper cables as shown above:

1. VCC to 5V
2. GND to GND
3. OUT to A0

Note: BE VERY CAREFUL and follow the above diagram while making the connections between your Heart BioAmp Candy & Arduino Uno R4, especially the GND and VCC else it may damage the sensor.

Connect the BioAmp Cable v3 to Heart BioAmp Candy.

Apply Nuprep Skin Preparation Gel on the skin surface where electrodes would be placed to remove dead skin cells and clean the dirt from skin. After rubbing the skin surface thoroughly, clean it with a wet wipe.

About Nuprep Gel:

Nuprep skin preparation gel is a mildly abrasive, highly conductive gel that should be applied before placing the electrodes on the skin to improve measurements. When applied gently, it strips away the top layer of skin and moistens the underlying skin layer which reduces the skin impedance with minimal skin irritation and discomfort.

Complete guide for skin preparation: https://docs.upsidedownlabs.tech/guides/usage-guides/skin-preparation/

So now we have 2 options to measure the ECG signals, either using the gel electrodes or using dry electrode based ECG band. You can try both of them one by one.

Option 1 - Measuring ECG using Gel electrodes:

1. Connect the BioAmp Cable v3 to gel electrodes,
2. Peel the plastic backing from electrodes
3. Place the IN- , IN+ and REF (reference) as shown above.

Complete guide on using gel electrodes: https://docs.upsidedownlabs.tech/guides/usage-guides/using-gel-electrodes/

Option 2 - Measuring ECG using Heart BioAmp Band, a dry electrode based ECG band:

1. Place the IN- cable on the left side, IN+ in the middle and REF (reference) on the far right side as shown above.
2. Now put a small drop of electrode gel on the dry electrodes between the skin and metallic part of BioAmp Cable v3 to get the best results.

Complete guide on using BioAmp Bands: https://docs.upsidedownlabs.tech/guides/usage-guides/using-bioamp-bands/

Download the Arduino IDE from the link given below:

https://www.arduino.cc/en/software

After downloading, connect the Arduino Uno R4 to your laptop using the USB Cable (Type A to Type C)

Note: Make sure your laptop is not connected to a charger and sit 5m away from any AC appliances for best signal acquisition

Copy paste the Arduino firmware given below in Arduino IDE.     

Chords Arduino Firmware: https://github.com/upsidedownlabs/Chords-Arduino-Firmware

Note: We are uploading UNO-R4 firmware as we are using Arduino Uno R4 but in case you are using Arduino Uno R3 then make sure to upload UNO-R3 firmware.

We will be using CHORDS which is an open source web application developed by us and it is designed for real-time signal visualisation, particularly tailored for bio-potential signals like EEG, EMG, ECG and EOG.

For this project, we will be using it to visualize ECG signals using the steps given below:

1. Visit https://chords.upsidedownlabs.tech/
2. Click on visualize now
3. Click on connect
4. Select the correct COM port and then click on connect to connect your development board to CHORDS
5. Now you will be able to visualize ECG signals.

CHORDS is equipped with a lot of features. Please find below some of the features which may be helpful for this project

1. Record and save data: You can record your ECG data in a CSV file and save it in your laptop for further analysis.
2. Freeze Stream: Freeze the stream to analyze the data. Resume the stream when you are ready to continue.
3. Zoom in / Zoom out: It gives you more control as you can either zoom in to look at specific data points or zoom out for an overall view.

Congratulations on successfully completing the project!

Let us know your feedback in the comments and feel free to ask any questions.

In case of any issues, you can check the following links:

1. Tips for best signal acquisition: https://docs.upsidedownlabs.tech/guides/troubleshoot/tips/#
2. Fixing hardware setup: https://docs.upsidedownlabs.tech/guides/troubleshoot/fix-hardware-setup/
3. Resolving software issues: https://docs.upsidedownlabs.tech/guides/troubleshoot/resolve-software-issues/

You can also mail us at support@upsidedownlabs.tech for any kind of support while you are making this project.