try to put some medium sized resistor in series with the piezo and see if it gets more tangible data input. Piezzos can output very high voltages.<br><br><div class="gmail_quote">2010/9/20 david lemarechal <span dir="ltr"><<a href="mailto:d_lemarechal@yahoo.fr">d_lemarechal@yahoo.fr</a>></span><br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div><div style="font-family: verdana,helvetica,sans-serif; font-size: 12pt;"><div><span style="font-family: times new roman,new york,times,serif;">Hi<br>
<br>I think the easier way to get info from the piezo is to plug it in a sound card preamp and then use [peakamp~ ]<br>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. <br>
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)<br>
The electronic part is not so difficult to build, I think you can get the schematic on the web.<br>Good luck<br><br>David<br><br></span></div><div style="font-family: verdana,helvetica,sans-serif; font-size: 12pt;"><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;">
<font size="2" face="Tahoma"><hr size="1"><b><span style="font-weight: bold;">De :</span></b> FernandoG <<a href="mailto:dataferx@gmail.com" target="_blank">dataferx@gmail.com</a>><br><b><span style="font-weight: bold;">À :</span></b> <a href="mailto:pd-list@iem.at" target="_blank">pd-list@iem.at</a><br>
<b><span style="font-weight: bold;">Envoyé le :</span></b> Lun 20 septembre 2010, 17h 58min 29s<br><b><span style="font-weight: bold;">Objet :</span></b> [PD] piezo sensor to pduino object<br></font><div><div></div><div class="h5">
<br>Hi <br><br>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.<br>
Anybody knows a efficient way to do this? how can i improve the accuracy?<br><br>Thanks ¡¡<br>
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<br></blockquote></div><br><br clear="all"><br>-- <br>Fagote / Contrafagote<br>Bassoon / Contra-bassoon<br><a href="http://myspace.com/ricardolameiro">http://myspace.com/ricardolameiro</a><br>