Aria Gen2 Device Calibration
Each Aria Gen2 device is individually calibrated in the factory to ensure accurate sensor measurements and proper spatial relationships between sensors.
Overview
Aria Gen2 devices contain multiple sensors with factory calibration data. Depending on the sensor type, calibration may include:
- Intrinsic calibration: Corrects for sensor-specific distortions and biases (e.g., camera lens distortion, IMU bias, microphone sensitivity)
- Extrinsic calibration: Defines spatial relationships (position and orientation) between sensors in the device coordinate frame (available for cameras, IMUs, and LED rings)
The calibration data is stored in a standardized JSON format and is accessible as Python DeviceCalibration objects through Client SDK or from Project Aria Tools.
Sensor Calibration Availability
The following table shows which calibration data is available for each sensor type:
| Sensor Type | Sensor Label(s) | Intrinsics | Extrinsics |
|---|---|---|---|
| RGB Camera | camera-rgb | ✅ FisheyeRadTanThinPrism | ✅ T_Device_Camera |
| SLAM Cameras | slam-front-leftslam-front-rightslam-side-leftslam-side-right | ✅ FisheyeRadTanThinPrism | ✅ T_Device_Camera |
| Eye Tracking Cameras | camera-et-leftcamera-et-right | ✅ KannalaBrandtK3 | ✅ T_Device_Camera |
| IMU | imu-leftimu-right | ✅ Accelerometer + Gyroscope (Bias, Rectification) | ✅ T_Device_Imu |
| Magnetometer | mag0 | ✅ Bias + Rectification | ❌ |
| Barometer | baro0 | ✅ Offset + Slope | ❌ |
| Microphones | mic0 - mic6 (contact-mic is not calibrated) | ✅ Sensitivity (dBV @ 1kHz) | ❌ |
| Speakers | LSPK, RSPK | ✅ Sensitivity (dBV) | ❌ |
Camera Projection Models
Details of the camera intrinsics model can be found in calibration insight
-
FisheyeRadTanThinPrism: Used for RGB and SLAM cameras
- Parameters: focal length (f), principal point (cx, cy), radial distortion (k0-k5), tangential distortion (p0, p1), thin prism (s0-s2)
-
KannalaBrandtK3: Used for eye tracking cameras
- Parameters: focal lengths (fx, fy), principal point (cx, cy), Kannala-Brandt distortion coefficients (kb0-kb3)
IMU Calibration Components
Details of the IMU models can be found in calibration insight
- Accelerometer: Bias offset (m/s²) and 3x3 rectification matrix for scale/cross-axis corrections
- Gyroscope: Bias offset (rad/s), rectification matrix, and G-sensitivity matrix
Device Coordinate System
Origin Specification
By default, the origin is located at the slam-front-left camera. All sensor transformations (T_Device_Sensor) defines device (i.e. origin) to be slam-front-left.
Coordinate Frame Convention
Aria Gen2 uses a right-handed coordinate system:
- X-axis: Points to the right when viewing from behind the glasses
- Y-axis: Points downward
- Z-axis: Points forward (out from the front of the glasses)
For more details on coordinate frame convention, please visit Coordinate Convention.
Additional Resources
- Coordinate Frame Conventions - 3D Coordinate Frame Conventions for Project Aria Glasses
- Client SDK API Reference - Complete API documentation
- Calibration Tutorial - Working with calibration data
- Device Profiles - Sensor configurations and profiles