Sensor Types: Which One?

[Q__Hybrid]

I'm back, inquisitive as always.

I want to create a project that uses several sensors to determine the distance between a common surface (wall) and its observers (people.)

The sensors must not create interference for each other. The data returned will be fed into digital potentiometers that will then be used to manipulate audio generators. The idea is to create a "wall of sound" that can be manipulated in real-time by the participating audience.

I would love to use lasers for this, but that would mean aiming radiation at the audience, plus I would have to design a very complex solution for detecting the reflected angles.

I could use supersonic sonar modules, but they would interfere with each other, as well as with the audio being emitted by the wall. Well, it's possible at any rate.

So, that leaves me with IR modules, right? If I'm wrong, let me know. Also, what would be the major hurdle in pulling off a design like this, aside from building all of the audio hardware from scratch?

That reminds me, I need to find plans for audio effects like Reverb, Echo, Flange, Overdrive, LFO, Panpot (using a digi pot, of course). So, if anyone knows a good schematics page...(audioguru?)

Thanks,
+Q__

 

[TekNoir]

Find a number of quite good DIY stompboxes and effects here -- http://www.generalguitargadgets.com/

There is a vast amount of support for many of the projects and I can even recommend them from personal experience. There are also links to a number of other very good sites with information and schematics for many more related projects.

 

[iso9001]

New cars use 4-6 ultrasonic sensors to detect if you are about to run over somthing in reverse. They don't interfere with each other.

 

[Nigel Goodwin]

New cars use 4-6 ultrasonic sensors to detect if you are about to run over somthing in reverse. They don't interfere with each other.

They probably use them sequentially, rather than simultaneously!.

 

[tansis]

Picking up on Nigel's point about sequential interrogation of the sensors
could something as simple as a "Theramin" circuit be used in large numbers as these can be constructed from little more than a handfull of logic gates and a capacitive plate/ antenna.

 

[Q__Hybrid]

Theremins are a terrific idea, but I'm fairly certain they require the participant to hang on to something metal in order for it to work.

I want the audience to be able to just walk in off of the street and be able to interact with this thing without having to do anything special. In most cases, people choose to hang back rather than dig in if audience participation is optional. I want to take away that decision so they don't have a choice.

I'll take a look at all of the stuff later on. Not enough time tonight.

Thanks everyone,
+Q__

 

[tansis]

http://www.geocities.com/SunsetStrip/Studio/2987/theremin.html

Theramins are so rare these days , gotta be fifteen years since I saw one played live on kids tv show. However the circuit is still used often to be found living the quiet life as a proximity sensor along long runs of chainlink fence at many a high security installation.
No physical contact is required to complete the circuit. Range varies and is a product of the oscilator power / RF output combined with the sensor plate area/ antenna length
[ oft found about 12" from the ground, cable tied to the fence with the electronics in plastic capped 3" metal pipe spaced every 30-50' will detect human body at two feet ..but I digress and must not ramble about my mispent youth]

 

[Q__Hybrid]

Sorry, I was vague in what I meant by "hang on to something."

As far as I know, theremins are not actually detecting the human body, but thinks like metal rings, zippers in clothing, things like that. If this is wrong and it is detecting the human body itself, awesome.

I watched a documentary about the official theremin device and I know that the volume of the emitted sound relies on the proximity of the performer's hand. When they actually hold on to the volume controller it's silent, but when they pull away it gets louder. I assume I'm gonna have to invert this somehow.

Thanks again,
+Q__

 

[Nigel Goodwin]

As far as I know, theremins are not actually detecting the human body, but thinks like metal rings, zippers in clothing, things like that. If this is wrong and it is detecting the human body itself, awesome.

They work by the capacitance effect of the hand near an RF oscillator, no metal required!.