I'm more impressed by the videos of the hand tracking around the keyboard than the tracker in the keyboard! Is that fidelity just using the Vive's outward facing camera? They don't show any tracking gloves in the mockups.
Its actually pretty simple. If you know where the keyboard is, you can clip out that part of the camera's input. Then you just need some edge detection to get the hand silhouettes.
And actually...that seems like a portable idea. So I suppose you could do this for any tracked thing.
And actually...that seems like a portable idea. So I suppose you could do this for any tracked thing.