Help me!

Hey,

I'm working on a project and getting a little nervous.

I need to get a make controller to communicate with pd.

The plan is that I get a piezo sensor hooked up to the make controller and then have the signal sent to pd. I want to get pd to play different sounds based on the value of the piezo.

I plan on making a presure sensing mat using piezo cable, I know I will need to amplify the signal to something that the make controller will be able to read, but I'm not sure what that would be.

I don' t have any experience with this and I'm not sure how how the make controller and pd will interpret the signals from the pressure sensing mat in order to get the results I'm looking for.

Any help is appreciated.

-Rich

Hi there - you may have some luck simply connecting the piezo to the analog inputs as the op amps on there make them pretty sensitive. If not, you might look around for an additional op amp circuit to boost the signals a bit. This is a pretty common circuit and there are lots of examples out there - maybe somebody here can suggest their own? In pd you'll most likely want to communicate with the Make Controller via OSC and you'll get values from 0-1023 depending on the value of the piezo. A pd-specific tutorial would be nice, but in the meantime you can probably get a good overview from the Max tutorial - http://www.makingthings.com/documentation/tutorial/max-msp

hello,

here are some examples of some circuits using piezos.

http://www.makingthings.com/Members/dudailev/images-of-circuits/Arduino.jpg/view
http://www.makingthings.com/Members/dudailev/images-of-circuits/Piezosensor_OP_amp_MC.jpg/view

i hope this helps

OK, I am calming down a bit. So the controller's ADC uses a reference voltage of up to 3.3V and amplifies the signal. The ADC is meant to read within the range of 0-3.3V and your output is scaled with 10-bit resolution. So if the signal from my piezo doesn't put out much voltage, I would be on the low end of the scale. I will have to hook it up and see if I'm getting values I can use... then decide if I need to amplify the piezo signal.

As far as communication goes, I'm thinking I will use the ethernet connection on the app. board and hook that up to my laptop. I will then have to determine how to get PD to communicate in OSC over the ethernet connection. I will have a look at the links you guys sent. Thanks.

-Rich