[PD] Re : piezo sensor to pduino object

[david lemarechal]

Hi

I think the easier way to get info from the piezo is to plug it in a sound card 
preamp and then use [peakamp~ ]
Otherwise you should do a bit of electronics to transform the tiny AC voltage of 
the piezo output into a DC amplified voltage to match the analog input of 
arduino. 

You'll have then to use [peakamp~] or something similar in arduino to be sure to 
take the highest value in a certain time, rather than take a "snapshot" of the 
analog input at the arduino clock frequency (like you would do for a knob)
The electronic part is not so difficult to build, I think you can get the 
schematic on the web.
Good luck

David





________________________________
De : FernandoG <dataferx at gmail.com>
À : pd-list at iem.at
Envoyé le : Lun 20 septembre 2010, 17h 58min 29s
Objet : [PD] piezo sensor to pduino object

Hi 

I need to use a piezo to trigger a bang in a pd patch but i am having some 
problem of inestability. I use the piezo like an analog input to arduino board, 
then comunicate with pduino ( firmata 2.1.) Once in the patch i use an arduino 
object to detect the signal from piezo and a threshold object to trigger a bang 
when the value of the signal goes up the threshold. The problem is the acuraccy 
of the sistem, because is really unprecise, sometimes trigger doestn work and 
some times trigger more bangs than hits to the piezzo.
Anybody knows a efficient way to do this? how can i improve the accuracy?

Thanks ¡¡



      
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