Ultrasonic tracking
Ultrasonic tracking is a kind of 3D tracking that uses high-frequency sound emitted from source components and received by microphones and software to detect the position of objects.[1] It uses ultrasound. It involves using an ultrasonic positioning system. It is done using an acoustic tracking system. It can be used to either track the position of an object, or its full position and orientation.
There are two explored classes of methods of acoustic tracking. One is to measure time-of-flight of the sound from the transmitter(s) to the receivers, performing multilateration. Another is to measure the phase coherence of the sound.[2] It is called phase coherent ultrasonic tracking.
Ultrasonic tracking requires "line of sight" but for sound. It can be done in a very small form factor.
It can use MEMS ultrasonic transducers.[3]
It can be used in a pen form factor.
Ultrasonic tracking was used by Ivan Sutherland's head-mounted display.
Phase coherent tracking was used by Ivan Sutherland in his head mounted three-dimensional display.[4]
Time-of-flight based[edit]
Examples of time-of-flight trackers are the Logitech 6DOF ultrasonic head tracker and the Fly mouse.[4]
For something like a pen, 5DOF tracking can be used, where a pen as two transceivers total: one at each end. In a 3D system where the user is only on one side, three counterpart transceivers can be used to sense the two transceivers from the pen. The full position of the pen is tracked, except for twisting the pen about its axis, which is fine.
Construction[edit]
Acoustic tracking systems may use sets of at least three ultrasonic sensors and at least three ultrasonic transmitters on devices in order to calculate the position and orientation of an object such as a handheld controller.[2]
Examples[edit]
An iteration of the Pico Neo headset uses ultrasonic tracking for its controller.[5]
Hybrid systems: IS-600 and IS-900
References[edit]
- ↑ 3D User Interfaces: Theory and Practice, page 98
- ↑ 2.0 2.1 "Pose tracking". 2017-04-11. https://en.wikipedia.org/wiki/Pose_tracking.
- ↑ "A New Tracking Technology in 3D space". 2024-07-31. https://article.murata.com/en-eu/article/new-tracking-technology-and-use-in-3D-interaction.
- ↑ 4.0 4.1 Mazuryk, Tomasz; Gervautz, Michael (1999-12-30). "History, Applications, Technology and Future". https://www.researchgate.net/publication/2617390_Virtual_Reality_-_History_Applications_Technology_and_Future.
- ↑ Hayden, Scott (2017-12-26). "Pico's New 6DoF Standalone VR Headset is Coming Westward, Including 6DoF Controllers". https://www.roadtovr.com/picos-new-6dof-standalone-vr-headset-coming-westward-including-6dof-controllers/.