Sonar Drawing Tablet
Posted by Ben-Goldberg@reddit | CrazyIdeas | View on Reddit | 8 comments
This drawing tablet looks like a clipboard, and is a clipboard, but it also has microphones on the corners and edges.
These mics listen to the sound of you drawing, and locate where your pencil is drawing using the difference in timing and volume of the sounds arriving at the mics.
It would probably also work if you drag a retracted pen or fingernail across the surface.
Almond_Tech@reddit
That sounds (pun intended) like it'd be very hard to make work well bc you'd have to prevent other sounds from messing it up
Ben-Goldberg@reddit (OP)
The more microphones it has, the more easily it could say "this sound originated from elsewhere, it can be thrown out."
One on each corner and edge is probably enough for a home or office environment.
L
Almond_Tech@reddit
But if a sound is like 10 feet away, it'd reach all the microphones at a similar volume and they'd all pick it up the same, and at the same time, how would it know the difference between a tap in the center, cough 10 feet away, or snap in the center? Maybe AI to identify what is a scratching sound or not? But that seems to be overcomplicating it imo lol
Ben-Goldberg@reddit (OP)
A sound from the ten feet to the left would arrive earlier to the microphones on the left side of the tablet.
A sound in the center of the tablet would arrive at the edge mics before it reaches the corner mics.
A tap in the center and a finger snap 🫰 in the center would be very similar, but the further away the snap is, the closer the sound arrival times would be to one another.
Almond_Tech@reddit
What about longer sounds though? Like a fan running or AC, someone singing or even talking, etc That would initially have whatever latency there is, but then become one long thing it wouldn't know what it is And it has to support long sounds bc otherwise scratching on the surface won't work
Ben-Goldberg@reddit (OP)
I expect that the sound "shapes" could still be matched up, and the differences between them measured.
Do submarine sonar systems get confused by a long sound source? I don't think so!
damontoo@reddit
This has already been done like 10 years ago using cheap piezo disks that detect the vibrations from the surface they're attached to. It was used as touch input for a projected display.
If you want stylus input that works anywhere, try a Quest 3/3S + the MX Ink stylus.
Ben-Goldberg@reddit (OP)
What did they call their piezo disk system?
Who made it?
Is it passive, relying on the sounds to be made by the user, or active, with ultrasonic emitters whose sounds get blocked by a finger?