Position and rotation tracking

Position and rotation tracking is the tracking of an object's position and rotation in space. 6DOF tracking is the tracking of the position and orientation of something in space. It is named 6DOF because it refers to the 6 degrees of freedom: three for position and three for rotation.

6DOF tracking is often called positional tracking. It is used in an absolute positioning system. One way is to do magnetic tracking. It can be done using a number of different hardware technologies, such as electromagnetic tracking and camera-based tracking. Methods of camera-based tracking include methods using SLAM or VIO.

Native simple 6DOF tracking solutions are necessary for robust 3D communication systems. This includes doing low level computer programming using a 3D tracking system. A 3D tracking system without computation dependencies is preferred.

Position can be represented in a computer system using a 3D vector. Rotation can be represented using a quaternion.

PnO tracking is related to rotation tracking, which uses 3DOF of space.

Methods

• Markerless inside-out tracking, which is camera-based tracking (SLAM/VIO)- This is used on headsets such as Meta Quest headsets and the Project North Star. An open source method is Basalt.
• Marker-based tracking - Camera based tracking that uses markers in the environment, which is simpler to implement.
• Electromagnetic tracking. Electromagnetic tracking requires an external source. It gets jittery when there is metal around, like a metal laptop computer. Magnetic tracking is typically wired, but it does not have to be.
• UWB tracking
• Mechanical tracking
• Acoustic tracking

Magnetic tracking

240Hz is generally sufficient if using Magnetic tracking with no filtering.

History

3D tracking has been used for motion capture for 3D animated movies.

The 3DOF regime of cheap tracking was embraced by Oculus VR with the original Oculus Rift. The CV1 of the Oculus Rift used (and the DK2) constellation tracking, which is a complex method of 6DOF tracking added on to a robust 3DOF system.