A Python library and example application for interfacing with the MyoMod EMG Armband via Bluetooth Low Energy (BLE).

The myomod_ble package provides a simple async stream interface to the MyoMod armband with built-in data recording.

python emg_viewer.py  # Launch GUI example application

import asyncio
from myomod_ble.connection import MyoModBLEClient, EMGDataType

async def run():
   client = MyoModBLEClient()  # or MyoModBLEClient(device_address="XX:XX:XX:XX:XX:XX")
   await client.connect()
   
   # Stream combined raw + filtered data
   async for pkt in client.stream([EMGDataType.COMBINED]):
      print(f"Raw: {pkt.raw}, Filtered: {pkt.filtered}")
      break
   
   # Get recorded data
   data = client.recorded()
   print(f"Recorded {data['raw_sample_count']} raw packets")
   
   await client.disconnect()

asyncio.run(run())

Two example applications are provided to demonstrate different use cases:

A minimal command-line example showing basic library usage:

python simple_example.py

That:

• Connects to a MyoMod device
• Streams combined EMG data
• Accesses recorded data
• Checks for packet loss

A more advanced, PyQt5-based graphical application with real-time visualization:

python gui_example.py

Features:

• Real-time EMG Visualization: Display 6-channel EMG signals using pyqtgraph (30 FPS)
• Dual View: Separate tabs for raw (1500 Hz) and filtered (100 Hz) EMG data
• Built-in Recording: Save EMG data to compressed .npz format
• Efficient Buffering: Deque-based data management with automatic limiting
• Clean Example Code: Demonstrates MyoModBLEClient integration with Qt (~350 lines)

What it demonstrates:

• Qt integration with async BLE operations
• Real-time plotting with frame rate limiting
• Recording control and data export
• Thread-safe signal/slot communication

• Python 3.8 or higher
• MyoMod Armband device
• Bluetooth adapter supporting BLE

1. Create a virtual environment (recommended)

   python -m venv venv
   source venv/bin/activate  # On Windows: venv\Scripts\activate

2. Install dependencies

   pip install -r requirements.txt

3. Run an example

   python simple_example.py    # Console example
   python gui_example.py       # GUI example

   or

# Setup script
./start_emg_viewer.sh

python simple_example.py    # Console example
python gui_example.py       # GUI example

• May require additional permissions for BLE access:

  sudo setcap cap_net_raw+eip $(which python)

• Or run the application with sudo (not recommended for production)

• Ensure Windows 10 version 1703 or later for BLE support
• May need to install Visual C++ redistributables for some packages

• macOS 10.14 or later required for BLE support
• May need to grant Bluetooth permissions in System Preferences

Recordings are saved as compressed NumPy archives (.npz):

EMG_Measurements/
└── emg_recording_20231212_143022.npz

File Contents:

• start_time: Recording start timestamp
• duration: Total recording duration (seconds)
• raw_sample_count: Number of raw data packets
• filtered_sample_count: Number of filtered data packets
• raw_sample_rate: Raw data sampling rate (1500 Hz)
• filtered_sample_rate: Filtered data rate (100 Hz)
• chnA, chnB, ..., chnF: Raw channel data arrays
• filtered: Filtered EMG data array
• raw_index, filtered_index: Packet indices
• state: Device state information

• Service UUID: f1f1d764-f9dc-4274-9f59-325fea6d631b
• Raw EMG UUID: 9c54ed76-847e-4d51-84be-7cf02794de53
• Filtered EMG UUID: 36845417-f01b-4167-afa1-81b322238fe1
• Combined EMG UUID: ab92c948-16ed-4ed2-b18e-d4c0a27808fc

• Channels: 6 (A, B, C, D, E, F)
• Sampling Rate: 1500 Hz (raw data)
• Raw Data: 15 samples per packet per channel
• Filtered Data: Single value per channel + state
• Data Format: IEEE 754 32-bit float (little-endian)

# Install dependencies
pip install -r requirements.txt

# Check Python version (3.8+ required)
python --version

# Test myomod_ble installation
python -c "from myomod_ble.connection import MyoModBLEClient"

• Device not found: Ensure MyoMod Armband is powered on
• Connection fails: Check Bluetooth is enabled
• Linux permissions: May need BLE access rights

  sudo setcap cap_net_raw+eip $(which python)

• Permission errors on Linux: Run with appropriate privileges or set capabilities

• High CPU: Check other background processes interfering with Bluetooth

• Path issues: Use absolute paths or verify relative path is correct

MyoMod-Python-BLE-Interface/
├── myomod_ble/
│   ├── __init__.py
│   └── connection.py          # MyoModBLEClient core library
├── simple_example.py          # Console example (~50 lines)
├── gui_example.py             # PyQt5 GUI example (~350 lines)
├── requirements.txt           # Python dependencies
├── start_emg_viewer.sh        # Setup and launch script
├── README.md                  # This file

MyoModBLEClient (myomod_ble/connection.py):

• Async BLE connection and streaming
• Built-in chunked data recording
• Packet index tracking for loss detection
• Support for raw, filtered, and combined data types
• Automatic device discovery

Example Applications:

• simple_example.py: Minimal async implementation
• gui_example.py: Full-featured Qt5 GUI with visualization