TrackIR
TrackIR is an optical motion tracking game controller for Microsoft Windows created by NaturalPoint Inc.. TrackIR tracks head motions with up to six degrees of freedom (6DOF) in later models, allowing handsfree view control for improved game immersiveness and situational awareness. Head position and orientation are measured by a purpose-built video camera, mounted on top of the user's monitor, which observes invisible infrared (IR) light (hence the name) reflected or emitted by markers on a rigid model worn by the user. TrackIR software is used to access and control the camera, as well as adjust tracking and manage game profiles. The ratio of actual head movement to virtual head movement can be changed, allowing the virtual head to turn 180 degrees whilst the user still looks at the monitor.

NaturalPoint have maintained the possibility of TrackIR eventually entering the video game console market.

History

The original TrackIR product was an affordable assistive technology device used for Windows cursor control. An early customer provided feedback to NaturalPoint that the product could be used in some flight simulators. This prompted NaturalPoint to re-brand the original device as SmartNav and launch a new TrackIR with improved gaming features to specifically target the flight simulation market. TrackIR was embraced by PC flight simulation enthusiasts who saw it as a better alternative to a joystick hat switch for view control. The technology used in SmartNav and TrackIR was later extended to another brand called OptiTrack, creating a more affordable professional motion capture solution.

Between 2002 and 2005, five different TrackIR camera models were released with steadily improving specifications. Frame rate doubled and resolution increased substantially, resulting in more responsive and accurate tracking. In 2003 the NaturalPoint President (also the principle hardware engineer) described these improvements to the original TrackIR as, "not critical for flight and driving sims, but very important to other types of games like first person shooters."

The TrackIR 3 was split into a cheaper standard model and a more expensive PRO model but the cheaper model was abandoned for the next version, TrackIR 4:PRO.

The TrackIR 4:PRO departs from the previous models' clamshell case with a new slim compact design, not much bigger than the diameter of a golf ball. It has a wider field of view than its predecessors and a new base so it can be attached to flat panel displays.

The TrackIR 5 was introduced in early 2009 with a similar design as the TrackIR 4:PRO. It features a wider field of view and higher resolution tracking sensor than previous models.

TrackIR interface with games

The proprietary TrackIR interface has become the de facto standard for view control in PC games and simulations and is only intended for use with TrackIR products. As NaturalPoint convinced more developers and games to support it, other devices inspired by the TrackIR have sought to access the same view control and been successful in reverse engineering the interface. This has allowed non-TrackIR devices to be used for view control, including common video devices like webcams.

Early on NaturalPoint updated the interface to require validation using text strings copyrighted by NaturalPoint, and only granted permission for use of the strings to game and simulation developers. This meant other applications wishing to use the interface without approval from NaturalPoint would have to risk potentially violating NaturalPoint's copyright. Proponents of third party head tracking devices which rely on the TrackIR interface for support in many titles believe the text strings are exempt and fall under fair use for the purposes of interoperability.

In October 2008 NaturalPoint changed the TrackIR interface and began encrypting the data stream sent to some new titles. Third party devices which had reverse-engineered the previous TrackIR interface were rendered incompatible with these new game titles due to the encryption. The older TrackIR-1 and TrackIR-2 products that use software drivers which are no longer maintained are also incompatible with titles using the new encrypted interface.

As of 20140610, the protocol version 5 has again been reverse-engineered, providing support for possibly all titles using the NPClient protocol.

Supported games

As of 2009 there are around 100 TrackIR Enhanced games that can natively use TrackIR cameras for view control with up to six degrees of freedom.

Criticisms

TrackIR 4 Pro

Some reviewers found the TrackIR 4 Pro with TrackClip Pro bundle to be expensive at the $200–$220 price, while still considering it a worthwhile purchase for serious simulation users. As of June, 2009 the bundle is available for $120.
Additionally, one review noted that the TrackIR 4 Pro runs at a temperature which they consider higher than normal when it is actively tracking.

TrackClip PRO

Some reviewers found the TrackClip PRO to have loose joints, be less durable than desired, and one was disappointed that it was unable to be positioned on the right side of the head, while still recommending the product.

See also
FreeTrack, an open-source and free head-tracking software which users can build their tracking hardware with webcams and infrared LEDs cheaply. Freetrack is no longer maintained.
 FaceTrackNoIR, an open-source and free head-tracking software which requires only a webcam and no infrared LEDs.
 opentrack, an active open-source project combining many features of FreeTrack and FaceTrackNoIR. Input sources include facial recognition, IR point tracking, paper marker tracking, and more.

References

External links
 NaturalPoint Inc. official website
 opentrack software project website

Video game controllers
Mixed reality
Tracking