I had this idea a few weeks ago, and noodled around, thinking about whether or not it could be done.Some of the hardware guys I know said it’s probably doable, but others said it’d be expensive and fragile and not precise enough. In order to have that conversation, though, I did a few sketches (I can’t draw to save my life!) and finally did a rigged demo to illustrate how it would work if it worked.
It wouldn’t actually work like an actual guitar; it’d be more like a Guitar Hero controller that could be used to jam along with a karaoke track or something like that.
I took some velcro, zip ties, wires, a remote audio amplifier and a camera remote control, and stuck it together so it looks about right, did the “demo” and then asked a friend who plays guitar to improvise appropriate sounds which I then rendered in to the final cut of the demo.
Several people started encouraging me to do a kickstarter for this. The problem is, I don’t think you could build a commercial version of this thing for under $250 a unit by the time you had all the R&D, which means it wouldn’t be cheap. And I hate the idea of doing a kickstarter in general: it’s like a start-up (I’ve done those!) where instead of having a board of directors as your boss, you have a great big flock of chickens. Instead of having 5 or 6 people telling you what to do, you’ve got thousands and they’re all contradicting eachother and yelling at you. Sounds like fun? I don’t think so.
Pierce R. Butler says
An air piano might be easier.
Marcus Ranum says
Pierce R. Butler@#1:
It’s been discussed. The piano would probably have to be a couple position sensors and some impact switches on the fingertip. Pianists I know say it would be unconscionable because you couldn’t feel the keys.
The guitarist who did the sounds for me said “I want one.”
Pierce R. Butler says
Call your friendly neighborhood patent attorney a sap!
komarov says
Okay, an interesting idea. However, wouldn’t this defeat the purpose of the air guitar, which, as I understand it, is that it always sounds good. Still, 21st century: everything must be gizmogrified. Today it’s the cheapest instrument there is, tomorrow you can get a used one for 600$ from ebay, if you’re lucky… (but at least its IOT-capable)
But your video with the hands moving about just screams ‘motion capture’ to me. I’m about as far from expert as can be, but it would seem to be the easier approach. Not only are there commercial kits out there for end uses and developers, I think the whole tracking system would a lot simpler. Instead of several battery-dependent sensor/transmitter units you might be able to get away with just a pair of gloves with optical markers on each joint and maybe the fingertips. I’m not even sure the markers are still be necessary; maybe tracking of the hands and fingers could already be done precisely enough without them.
The fingertips might present a problem though as they’re probably the most important bit (speculated the non-guitarist loudly) and barely visible to the cameras, if at all. My ad hoc solution: RFID-tags in each tip, with a flexible battery and charging mechanism sown right into the glove. (Recharging could be done e.g. from elastic stretching of the fabric.) The receiver / scanner could be added to the motion capture unit.
Not that I play the piano well (wrong side of the spectrum) but maybe that’s precisely why I’d loathe anything with the wrong ‘tactile feedback’. Not being any good I get confused that much more quickly when things feel or sound different, because I start thinking ‘wrong‘. At one point I briefly considered getting one of those piano-mats but dismissed the notion for that very reason. Well, that and their apparent inability to handle more than two or three notes at once, which would make it a piano that can’t play chords and barely accomodates two hands.
consciousness razor says
Right, it’s not just an arbitrary button attached to a black box that spits out a pre-recorded noise when you push it. There are very precisely-engineered mechanisms for hammering the strings when you press a key and use the pedals. (Which is part of the reason good ones cost tens of thousands of dollars…. So if it worked well, a lot of people would very happily pay a few hundred bucks, Marcus!)
Anyway, it shouldn’t be hard to imagine the details of the sound have a rather complicated relationship with exactly what those mechanisms and the string(s) are doing at every moment, in response to a sort of violent act that has all sorts of wild effects. At first glance, the algebra and such looks nice and clean and simple, but it gets pretty messy when you have to apply it to a bunch of physical objects. The important point is that a pianist has control over some of that, by pressing a key more or less forcefully, holding it down for some amount of time, slightly altering the timing/duration of the pedal(s), and so forth. Most wouldn’t want to lose that.
A guitarist (or any instrumentalist) is in a similar situation, although some may not worry as much as others of course. It’s still the same basic set of problems, about how you’re physically modeling the strings and the box and various methods of getting the strings to move.