Ultrasonic tracking
Ultrasonic tracking is a kind of 3D tracking that uses sound waves. It uses high-frequency sound emitted from source components and received by microphones.[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 classes of methods of acoustic tracking. The first is to measure time-of-flight of the sound from the transmitter(s) to the receivers, performing multilateration. The second is to measure the phase coherence of the sound.[2] It is called phase coherent ultrasonic tracking.
It requires line of hearing, which is essentially the same as line of sight. 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 Mattel Power Glove.[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/.