Getting Pressure Sensitivity on Piezo "drum"


So I am trying to make a pressure sensitive "drum". I want the pressure sensitivity to be translated to an openframeworks application, ie the harder you hit the farther/harder an image will "fly".

I have tried the "Knock" program, and it seems to be working fine. I modified the program to just spit out the value it gets from the AnalogRead() and I only get useful information when I am directly tapping the sensor, if I tape it to a table or box, I barely get anything. I don't need it to be intensely accurate, but I do need some indication that the force I hit is causing a proportional reaction.

so my questions are:

I have a pile of old telephone mouthpiece microphones, I am using them inside a practice drum pad for picking up drum strikes. Started this project in 1989-1990, then we bought a house and moved and it went into a box. I am resurrecting the project now with arduino-based controller to play back sound from SD card. Have to dig up my opamp & ADC/DAC schematics, had all the trigger circuitry working to amplify & capture strike "volume" to control playback volume of sound sample stored in SRAM. Making inexpensive PCBs now will really let this thing take off once I get a little free time from making designs for other folks!

hey crossroads, that sounds cool, please upload if you get a hold of any of that stuff.

I think for now I am going to try FSR's based on this:

(see figure 6).

and a bunch of other FSR + arduino videos on youtube.