High Accuracy + Low Latency for
Tight Spatial Synchronization

December 3, 2018

How it Works

Technology Overview

Atraxa combines electromagnetic (EM) and inertial technologies into a single sensor-fusion tracking platform. The IMU (inertial measurement unit) returns acceleration and angular velocity data from an accelerometer and gyroscope. The EM tracker delivers true position and orientation data.

When used alone, IMUs are prone to measurement drift. The EM tracker acts as a ground truth reference, improving the accuracy of the IMU positional data. The EM tracker also establishes the measurement volume and local coordinate system in which movement is tracked.

Atraxa is comprised of two main components: a tracker module and receiver module. The tracker module houses the IMU and an EM transmitter coil that generates the magnetic field (i.e. the measurement volume). The tracker modules are embedded into the handheld controllers (or other peripherals).

The receiver module is found inside the headset; it’s the ‘brains’ of the platform. The receiver module measures the magnetic field; calculates the 6DOF pose of each peripheral device; and serves the fused or unfused pose data to the OEM host application. The position and orientation of the controllers (trackers) are reported relative to the headset’s (receiver) position.

Data synchronization between the tracker and receiver modules is achieved via an accurate timestamp. This data, along with peripheral device data (i.e. game actions) is communicated wirelessly via the BLE (Bluetooth® Low Energy) protocol. The pose data is transmitted to the OEM host application via BLE or USB.

How it Works

  1. Transmitter coil generates the magnetic fields
  2. EM sensor detects the magnetic field and produces position and orientation data
  3. IMU produces acceleration and angular velocity data
  4. IMU data is sent to the receiver via BLE
  5. Timestamp synchronization and peripheral device data (game actions) are sent via BLE
  6. Receiver calculates accurate and continuous 6DOF data from EM sensor and IMU
  7. Receiver serves 6DOF data to the OEM host application via USB or BLE

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