Speak With Your Eyes: Build a Mind-to-Words (M2W) Interface

What if a person who cannot speak could still express basic needs using only eye blinks? In this project, we explore the world of Human-Computer Interaction (HCI) and Brain-Computer Interface (BCI) by creating a system that translates eye blinks into spoken words.

Mind to Words (M2W) is a communication system designed to help ALS patients and individuals with limited voluntary movement interact with their environment. Using the Neuro PlayGround (NPG) Lite—a powerful, wireless bio-potential sensor—we capture tiny electrical signals from the eyes (EOG) to control a speech-assistance application.

This is a completely "hands-free" communication tool. By capturing these bio-potential signals, users can hover through a menu of six essential needs—Water, Food, Washroom, Help, Outing, and Television—and select them to be spoken aloud simply by blinking. This low-cost assistive technology provides a vital voice to those who need it most, turning biopotential signals into meaningful human connection

Supplies

Hardware:

• 1 x NPG Lite
• 1 x Vibz Playmate
• 3 x BioAmp Snap Cables
• 3 x Gel electrodes
• 1 x Nuprep skin preparation gel (Optional )
• 1 x Alcohol swab
• 1 x Laptop

Tip: You can get everything in the Ninja Pack From ROBU.IN, , Upside Down Labs online store , International Customer (Tindie)

Software

• NPG Lite Flasher web Application
• M2W Web Application
• Chromium-based browser (Google Chrome, Brave, or Microsoft Edge) for the M2W app.

Step 1: Skin Preparation

• Apply a small amount of Nuprep gel (optional)
• Gently rub on electrode placement areas
• Clean with alcohol swabs

This removes oil and dead skin, improving signal quality

Step 2: Connecting BioAmp Cable:

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

• Positive of Channel 1 to A0P
• Negative of Channel 1 to A0N
• Reference cable to REF

Step 3: Electrode Placements

Measuring EEG using Gel electrodes:

• Connect the BioAmp Cable to gel electrodes,
• Peel the plastic backing from the electrodes.
• Place the cable connected to A0P between the Fp1 and Fp2 positions
• Place the cable connected to A0N on the bony part behind the earlobe on one ear.
• Place REF on the bony part behind the earlobe of the other ear.

Step 4: Powering ON the NPG Lite

Before connecting the device to the software, we first need to properly power the NPG Lite.

• Connect the battery cable properly to the NPG Lite board to power the device wirelessly. Make sure the connector is securely attached before starting.
• Turn ON the NPG Lite board by switching the ON/OFF button to the ON position. The board is now ready to connect and use.

Step 5: Uploading the Firmware

• Connect NPG Lite to your computer via USB
• Open NPG Lite Web Flasher.
• Click Connect → Select USB JTAG
• Click Get from GitHub → Select “BCI-Blink-BLE”
• Flash firmware

Once done, disconnect USB — the device will work wirelessly.

Step 6: Connecting to M2W App

• Open the M2W Web app in chrome/brave: https://upsidedownlabs.github.io/M2W/
• Turn on Bluetooth (Note:Just turn on Bluetooth and donot manually connect NPG Lite to bluetooth)
• Click Connect to scan for BLE devices.
• In the dialog box, select ESP32C6_EEG (your NPG Lite device).
• Once connected, electrode signals are streamed in real-time.
• Try blinking:

1. Double blink: Hover menu items

2. Triple blink: Speak/select the option

Step 7: How It Works?

The system detects blink patterns:

• Single Blink: No action
• Double Blink: Navigate through the menu
• Triple Blink: Select the option and speak it out loud

Step 8: Performance Tips

• Perform strong, deliberate blinks rather than natural eye flutters.
• Sit still, keeping your head steady and jaw relaxed to avoid muscle artifacts.
• Stay at least 5 meters away from heavy appliances (microwaves, fluorescent lights) to reduce electrical noise.
• Ensure firm electrode contact with the skin.

Step 9: Quick Troubleshooting

• If the signal is poor, clean the skin, reapply gel, and check placement.
• Verify the BCI-BLINK-BLE firmware is flashed and select ESP32C6_EEG when pairing.
• Keep the NPG Lite within 10 meters of your system.
• If the browser won't scan for Bluetooth, type chrome://flags in your URL bar, enable Web Bluetooth, and restart the browser.

Step 10: Applications & the Future

• Current uses include assistive communication, hands-free accessibility, and BCI/HCI education.
• Future upgrades aim to include machine learning classification, custom blink patterns, free-form text-to-speech, and multi-user profiles.