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Electronics => Electronics => Topic started by: clone on March 08, 2009, 04:35:56 AM

Title: drum sensors?
Post by: clone on March 08, 2009, 04:35:56 AM

im sure its been done before.. but what im trying to figure out is what kind of sensors to use to detect when a drum is hit.  The project is for a psychedelic lighting system for a concert.  It will turn on certain light sequences depending on what the band does with their instruments.  the guy on drums wants whatever drum / symbol he hits to light up.  So what kind of sensor would you suggest to attach to the drum or symbol to detect when it gets hit??

like i said im sure its been done before... i'd be happy just copying whatever they did.. lol

Title: Re: drum sensors?
Post by: paulstreats on March 08, 2009, 07:16:40 AM

I know somebody who has some drums, hes got some small sticky pads that go on them and then to an amplifier. Probably a thin film piezo microphone. They are commercially available

Title: Re: drum sensors?
Post by: Soeren on March 08, 2009, 11:51:23 AM

Hi,

This can be done in several ways. The easy part is sensing the hit, but differentiating eg. a rim shot from a regular beat and whiskers vs. drum sticks may be a bit more work.

Sensors for the impact can be; Piezo disks, ferrite core coils, several types of microphones (but they will be sensitive to other sound as well), a magnet and pickup coil (or linear Hall element) and so on.
Coils will not sense other sound, but may be prone to picking up magnetically induced noise, piezo might sense other sound, depending on how it's done, but is not sensitive to magnetic fields.
Several parameters must be judged against each other, as well as your ability to mount the sensor, which will differ depending on choice of sensor.

So, what kind of precision is needed?
And what output do you need?

Title: Re: drum sensors?
Post by: clone on March 08, 2009, 08:34:01 PM

i want it to sense the hit when you hit the drum with a drum stick.. but not pick up other vibrations or sounds.  peizo disks sound like a good option.  i'll probably be using an arduino board to hook it all up to.

Title: Re: drum sensors?
Post by: clone on March 09, 2009, 09:34:47 PM

i need it to be something that can easily be put on and taken off the drum kit..

i was thinkin maybe something like an ultrasonic sensor that u could clip onto the lip of the drum, and it would be about 1/16" away from the drum surface, and measure the vibrations that way.  just wondering if there are ultrasonic sensors that accurate? any othr suggestions?

or maybe a little microswitch that rests on the surface of the drum, and when the drum is hit it moves the surface of the drum down slightly which is just enough to trigger the swtch? hmm

Title: Re: drum sensors?
Post by: Admin on March 25, 2009, 12:39:51 AM

You could mount an accelerometer to the side of the drum . . .

Title: Re: drum sensors?
Post by: SmAsH on March 25, 2009, 02:11:03 AM

would that not be like crazy expensive?

Title: Re: drum sensors?
Post by: Asellith on March 25, 2009, 05:47:35 AM

Ok time for a KISS solution. a weighted rod that is mounted to the side of the drum. It will need a limit switch attached to it and a fulcrum at the right point to let it bounce up every time the drum is hit. The weighted end will pull it back down to rest on the drum but the slight bounce needs to be enough to trigger the switch then attach that to your lighting equipment (LEDs or whatever).