Ultrasonic fingerprint readers have made their mass-market debut, but there are other uses for ultrasonic technology in today’s gadgets. For example, TDK subsidiary Chirp Microsystems is powering a number of Virtual Reality (VR) systems, including the HTC Vive Focus and the Qualcomm Snapdragon 845 Mobile VR.
Both VR headset use 6-DoF, which means Degrees of Freedom. It means that the user can not only look around by turning his/her head around but can also move forward, backward, left, right, up and down. This is key to having immersive 3D worlds.
The SonicTrack chip’s role is to provide the data that make it possible to position the VR controllers relative to the headset, from the inside out.
From a consumer standpoint, it is much more convenient than having to setup infra-red (IR) equipment around the play area. Read our HTC VIVE Pro review if you’re not familiar with the external trackers concept.
But perhaps “how” SonicTrack works is the most impressive part. Despite being tiny, it is capable of sending ultrasonic waves 240 degrees around it, then use the bounce-back signal to construct a dataset of the surrounding. The technique is called Time-Of-Flight (ToF).
This technique for tracking controllers is also much less computationally expensive than if developers were using RGB cameras to perform the same task.
By being able to know precisely where the controllers are, wire-free VR headsets can execute the most complex VR applications that require minute positioning of the controllers (longbow, precise fencing, using virtual tools, etc.)
The first generation sensor called CH-101 could track to a distance of 120cm. But the newer CH-201 model can sense up to 500cm away, making virtually all gaming accessories, including sticks, swords, or replica rifles manageable and accurate.
When we tried the demos, things felt quite precise, and the responsiveness was good as well. At the moment, it doesn’t quite rival bulkier systems, but the added convenience, ease of setup and lower price makes SonicTrack a desirable solution.