Hi! I'm a total newbie in the world of PD and look for help finding a a way to create a patch that triggers sound with a sensor (IF movement)+eobody sensor box(connects with usb to a computer). Id like the sound to be started when someone gets in to the zone of the sensor and stop when stepping out of the zone. If it's possible to have the wav file doing pause and continue from pause forward on the sound when stepping in and out of the zone that would be even better.

The installation is for and old radio, idea is that it would seem to haunt or work on it's own. I will put the speakers and computer in side the radio and plan to direct the ray towards the people walking in. Or maybe pointing upwards, so that it will detect the movement only when somebody comes really close. It's for an exhibition of my art diploma. I love working with sound but I'm not yet familiar with pure data.

The thing that worries me is the sensor, if its too sensitive and sound will be played too easily and won't stop + the sensitivity of the sensor. Would an external webcam be a better solution?

The other problem is that I'm a total newbie. I tried to look the patches, and as far as I could get something from it, it seems that I need the patch to read the sensor, and and a patch that triggers the sound. How can I connect those two? The only things I could find where too complicated and often with video or for midi which is no my case. Do I have to have arduino or is it possible just with pd extended?

Do you have experiences using sensors for triggering sound, please help, I think aI need it badly !
Thanks,
Julia

You don't necessarily have to use an Arduino, but it's probably the easiest solution. Pd-extended comes with the [Pduino/arduino], which makes working with the Arduino really easy if you aren't familiar with how to program it. You just have to load the Standard Firmata to the Arduino board, and everything else can be done in Pd, so you don't need to learn how to use both languages. You just have to make sure your sensor is connected properly.

It sounds like a simple IR distance sensor might be just fine for this. As far as the sensitivity goes, that's just something you'll always have to work around when dealing with sensors. But really, all you would need is to set a threshold for when someone is close enough to trigger the audio and one for when someone is far enough to turn it off. If you don't have a different value for both, you can get some nastiness when someone is standing right at the threshold. You can set that up like this:

[moses 10] <-- whatever your "off" threshold is
| |
| [moses 20] <-- "on" threshold
| /
[0( [1(
| /
| +-----------+
|/
[change]

On the audio side, for your needs I would suggest taking a look at [readsf~] and/or [tabplay~].