Your First Steps to HCI/BCI Projects

This instructable provides a step-by-step guide for configuring your Neuro Playground Lite to record and visualize EEG, ECG, EOG, and EMG signals using the CHORDS Web, an open-source web application.

Electromyography (EMG), Electroencephalography (EEG), Electrooculography (EOG), and Electrocardiography (ECG/EKG) are techniques used to measure the electrical activity of muscles, brain, eyes, and heart, respectively. These measurements can be applied in various projects for controlling devices.

Hardware:

1. Neuro Playground Lite
2. Vibz Playmate
3. Gel electrodes
4. BioAmp snap cables
5. Nuprep
6. Alcohol swabs
7. A laptop with a USB-C cable

Software:

1. NPG Lite Flasher
2. Chromium-based web browser
3. Chords web interface

About Neuro PlayGround (NPG) Lite

Neuro PlayGround (NPG) Lite is a compact Adafruit Feather form factor, a 3-channel wireless biopotential signal amplifier designed for EMG, ECG, EOG, and EEG recording.

It offers Wi-Fi, Bluetooth, Zigbee, and Thread connectivity, along with patient protection, LEDs (User LED, charging LED, six addressable RGB LEDs), buttons (Reset and user button), LiPo battery charging, and USB-C with ESD protection. Its lightweight and user-friendly design makes it perfect for research, education, and wearable applications.

Neuro PlayGround Lite will be available soon on CrowdSupply. Subscribe now to never miss out on any updates.

1. Power On: Toggle the switch on your Neuro Playground Lite to turn it on.
2. Download Flasher: Download and install the NPG Lite Flasher from the provided GitHub link.
3. Connect: Connect your NPG Lite to your laptop using a USB-C cable.
4. Select Firmware: Open the NPG Lite Flasher. Choose BLE firmware from the options.
5. Identify Port: Identify the correct serial port for your NPG Lite.
6. Flash: Click the Flash button to begin the firmware upload.
7. Disconnect: Once the firmware is flashed, unplug the NPG Lite from your laptop.

Important: Disconnect your laptop's charger to minimize AC noise during data acquisition.

Proper skin preparation is crucial for clear signal acquisition.

1. Apply Nuprep Gel: Apply Nuprep Skin Preparation Gel to the areas where electrodes will be placed. This gently exfoliates the skin, removing dead cells and oils.
2. Clean with Alcohol Swabs: After applying the gel, clean the prepared areas thoroughly using alcohol swabs.
3. Electrode Placement Areas:
4. EMG: Flexor carpi radialis muscle (forearm).
5. ECG: Both wrists.
6. EEG: Forehead and the bony area behind both ears.

What is Nuprep Gel?

Nuprep is a mildly abrasive, highly conductive gel that improves electrode contact by reducing skin impedance. It's safe, effective, and causes minimal skin irritation which gently exfoliates the top layer of the skin, removing dead cells and oils that can interfere with signal transmission

Once your skin is prepared, it’s time to connect BioAmp Snap Cables.

Connect the BioAmp Snap Cables to your NPG Lite .

1. Channel 1 (EMG): Connect to A0P (positive) and A0N (negative).
2. Channel 2 (ECG): Connect to A1P (positive) and A1N (negative).
3. Channel 3 (EEG): Connect to A2P (positive) and A2N (negative).
4. Reference Cable: Connect one cable to the REF port.

Channel 1 (EMG): Snap the positive and negative cables to two gel electrodes. Place these electrodes on your flexor carpi radialis muscle (forearm).

Channel 2 (ECG): Snap the negative cable to an electrode on your left wrist and the positive cable to an electrode on your right wrist.

Channel 3 (EEG): Attach the positive cable to an electrode placed on your forehead (between Fp1 and Fp2). Attach the negative cable to an electrode placed on the bony part behind one ear. Place the reference electrode on the bony part behind the other ear.

Follow the steps given below to use Chords Web, a web application for recording and visualizing EEG, ECG, EMG or EOG.

1. Open a Chromium-based browser like Google Chrome, Microsoft Edge, Opera, Brave, etc.
2. Search chords.upsidedownlabs.tech
3. Click on "Visualize Now."
4. Select "NPG-Lite" from the options at the bottom of the screen.
5. Ensure Bluetooth is enabled on your system (no manual pairing needed).
6. Click the "Connect" button to scan for available devices.
7. Select your NPG Lite from the list to begin real-time visualization.

Interface Features: The interface allows you to:

1. Select which channels to visualize.
2. Adjust the zoom level.
3. Play/pause the data stream for analysis.
4. Apply bandpass filters for EMG, ECG,EOG,EEG, and 50/60 Hz notch filters.
5. Record data from all channels and save it as a CSV file.

Disconnect: When you're finished, click "Disconnect."

This was just a demonstration of how Neuro PlayGround Lite can record, filter, and process 3-channel biopotential signals (EEG, EMG, EOG, ECG).

This is just the beginning. We are already working on creating much more interesting brain-computer interfaces and human-computer interfaces.

The possibilities are endless. Drop your feedback in the comments.

Need help? Reach out at support@upsidedownlabs.tech

Getting an accurate signal is very crucial . Please check the link below for the tips for best signal acquisition: https://docs.upsidedownlabs.tech/guides/troubleshoot/tips/index.html

In case a weak signal is detected, then ensure there is good electrode contact with the skin surface and you have prepared the skin using nuprep skin preparation gel properly.

If you face any issues with the Bluetooth connection, then restart NPG Lite and try to reconnect.