Orienta is a 3-DOF head-tracking application for Windows. It reads accelerometer and gyroscope data from a serial-connected IMU, estimates yaw, pitch, and roll with a complementary filter, and sends orientation data over UDP into opentrack.
The idea is to be able to track your head movements in games. Some huge names in the business are trackIR and Tobii, but their complete kits can be quite expensive, making the cost of entry into immersive simulation games quite high.
While you can build your own kit, you would typically need an IR-sensitive camera with a high frame rate, carefully consider camera distance to head, design a clip for holding the 3 LEDs - it's possible, but can be tricky to get good results with.
The space between these options is where Orienta could work for you. While there are some shortcomings to using an IMU, the arguments for it are compelling: You can build your own for probably under 15$, are completely free of any camera or viewing angle calculations, it works the same whether your room is brightly lit or pitch black, and can track your head movements at over 240hz, giving you a buttery smooth experience.
The only diy required is soldering up your sensor and your board and mounting it to your headset. Example included further below.
- Real-time serial IMU acquisition with support for a wide range of sensors
- Quaternion-based complementary-filter implementation
- Gyro-bias calibration and correction
- Smooth autocentering when stationary and near center
- PyQt5 interface with light and dark themes.
build\dev\setup_dev.bat creates a virtual environment, installs dependencies, and creates a desktop shortcut, if you so desire.
git clone https://github.com/anmagx/Orienta
cd Orienta\build\dev\
python -m venv .venv
.venv\Scripts\activate
python -m pip install -r requirements.txt
cd ..\..\
python orienta.pyAfter running build\dev\setup_dev.bat, build a single-file, windowed executable with:
build\build_exe.batThe script installs the pinned build requirements and creates build\dist\Orienta.exe
from build\orienta.spec. The executable includes the application icon, logo,
and themes. Preferences and logs are stored outside the executable, as described
in User data.
- Windows Operating System
- Python
- PySerial
- PyQt5
- Keyboard
- Pygame
- PyInstaller
Any device that emits numeric CSV values on a serial port is supported. The bundled firmware is an ESP32-C3 Super Mini example using a FastIMU-supported MPU6500, configured to run at 500000 baud. The project prototype used an Arduino Nano. The sensor data must be structured as follows:
time_seconds,accel_x,accel_y,accel_z,gyro_x,gyro_y,gyro_z
Accelerometer values are expected in g units and gyroscope values in degrees per second. Configure the serial port and baud rate in the application to match your device.
Magnetometers are currently not supported.
You will obviously need to find a way to mount your sensor on your head. In the example I use a 3D-printed case for the sensor itself and the arduino nano that both clip to my headset. Many, if not most IMUs will want to be mounted a specific up-direction to give accurate accelerometer readings - tilted on the side or on it's head will probably not work, but flipped 180° is fine. The app allows for flipping axis in the preferences section.
- Flash the supplied Arduino sketch, or connect a compatible IMU source.
- Select its serial port and baud rate, then start the serial reader.
- Keep the device still and level while calibrating gyro bias.
- Mount the device, reset orientation as needed, and enable UDP output.
- Configure OpenTrack to receive UDP packets at the selected address and port.
Orienta always sends zero translation and orientation as yaw, pitch, and roll.
Preferences and logs are stored in %LOCALAPPDATA%\Orienta, for both source
and packaged executable runs. The directory is created automatically:
config.cfgstores user preferences.orienta.logstores application logs; rotated logs remain in this directory.
If LOCALAPPDATA is unset, Orienta uses AppData\Local\Orienta under your home directory.
Check out the example device in action here!
Orienta is distributed under the MIT License.