detect single water drops with touch sensor

hi there !

i was curious if somebody has already created sth similiar:

for an audioinstallation i need to detect singel waterdrops that fall onto aluminium-foil from 3meter height. (one waterdrop falls every 60 seconds).
in maxmsp (i use arduino2max) the drop then triggers various audioprocesses.

i used a piezzo-pick and a threshold-detection within max so far which works somehow, but it is not so precise as i need it and somehow , since a waterdrop is a very fast and not too strong impuls, it can be triggered also to easy by other things as well (exspecially sudden rapid changes of the serial communication).
which makes me not a 100% happy.

so i was just curious if anybody has an suggestion for a certain touch senor that would work for this?

any other ideas are welcome !

cheers,

peter

I did this many years ago when investigating chaos from a dripping tap. I use an IR beam and sensor to pick up the drop close to where it left the nozzle. This worked very well and was quite easy to set up.

thank you. i was thinking about that too but i donĀ“t likr the idea that the detector is visible for the visitors, while i could "hide" the piezzo underneath the aluminium foil...

anyways, do you have any suggestions concerning a certain type of IR beam sensors for such an installation?

This is a link to my 1994 article on it.

http://www.doc.mmu.ac.uk/STAFF/A.Wiseman/Acorn/BodyBuild/BB_94/BBC132.txt

http://www.doc.mmu.ac.uk/STAFF/A.Wiseman/Acorn/BodyBuild/BB_94/BBC132.TIFF

P.S. I no longer work at that University and a collogue kindly hosts my old pages.

EDIT Just tried the TIF file and it appearers to be missing, I will put up something else tonight (U.K. time)

I did this many years ago when investigating chaos from a dripping tap.

As you do... :D

--Phil.

OK here it is, I was also timing the drop from the passage through. You will see the double pulse as the drop passes the sensor. I used a latch so that the computer wouldn't have to sit continuously looking for a drip and so it would never miss one if it was off doing something else when the drip happened.