Physiological recording using BITalino
- 3 minsThis is the official BITalino website.
The EMG sensor datasheet provides a general description of how the sensor works, the typical shape of raw EMG data, bioelectrical specifications, and electrode placement guidelines.
The OpenSignals software overview video introduces the main features and operations.
Materials and Equipment
- BITalino Core BT (MCU+BT+PWR): The main board that enables real-time data streaming. Details can be found here, including a diagram of the functional blocks and components.
- 1500 mAh 3.7 V battery
- EMG sensors: Built specifically for measuring muscle activity
- BITalino sensor cable (100 cm): Connects the EMG sensors to the main board
- 3-lead electrode cable: Connects the EMG sensors to the electrodes
- Disposable Ag/AgCl electrodes*: Standard pre-gelled, self-adhesive disposable electrodes
- 3D-printed casings: Protect the circuit board and sensors for durability
*The number of electrodes varies depending on your needs.
Get started with using BITalino for physiological measurements
Before recording signals, please review the BITalino Quickstart Guide.
Step 1. Install the software
Download the OpenSignals software from this link. For more details, see the OpenSignals datasheet.
Step 2. Connect the battery
Attach the 3.7 V battery to the main board and switch on the power.
Step 3. Establish bluetooth connection
Open the OpenSignals software and connect your computer to the main board via Bluetooth.
Enter the password 1234 when prompted (see p. 18 of the user manual).
Click the GUI symbol at the bottom to “Find and configure your devices.”
Step 4. Select channels
The main board has six available channels (see the back of the board). Select the number and type of channels you want to use (e.g., A1 & A2 for EMG), and disable the others by deselecting the blue dots.
Note: a blue dot means the channel is already active—no need to click “Enable” again.
Step 5. Configure file saving
Click the GUI symbol at the bottom to “Change OpenSignals settings.” Here you can:
- Choose the file format (.txt, .h5, .edf). A .txt file is sufficient for processing in Python or MATLAB.
- Specify the save location for your recordings.
For details, see the file formats description.
Step 6. Connect electrodes
Assemble the setup by connecting:
- Sensor cable → EMG sensor
- EMG sensor → 3-lead electrode cable
Ensure the channel number matches the sensor selected in Step 4.
Important: The EMG sensor has two sets of outputs:
- The socket labeled A1, AVCC, REF, GND connects to the main board.
- The socket labeled IN-, REF, IN+ (marked “EMG” on the side) connects to the 3-lead electrode cable.
If connected incorrectly, the bipolar recording system will not work.
Step 7. Place the electrodes
Attach the gelled Ag/AgCl electrodes to the 3-lead cable and place them on the target muscle.
The middle electrode serves as the reference/ground.
Step 8. Record data
Click the red Record button to start acquisition.
When finished, click “Start the file viewer on the current file” to review your recording.
You can also watch this video for a demonstration of OpenSignals features, including generating reports.
The data are now saved in your chosen location and ready for processing.
Common Issues and Troubleshooting
Bluetooth connection issues:
Sometimes a Bluetooth error may occur. If this happens:
- Turn Bluetooth off and back on, or delete the existing BITalino connection from your computer.
- Reconnect by entering the PIN again.
See p. 185 of the user manual for a full error list, or refer to the dedicated Bluetooth troubleshooting guide.
Additional Resources
