standalone proximity sensor trigering MP3 playback

Hello,

I am currently looking at the feasability of a project involving playback of audio triggered by the presence of a person entering a 3m area. The sensor/arduino/playback device/loudspeaker would be packaged and put in a tree. When someone walks near the tree, the playback starts. I think I can handle the programing, I just need help with some basic feasability questions:

I have experience using the SRF404 sensor and arduino hooked up to Processing triggering a sound oscillator.

This worked, and actually the ultrasound sensors worked well at picking up people.

For my current project I would like to do away with the PC and have the arduino trigering a standalone audio playback board, is this possible ? I would need to store , say 5 MP3's and have them triggered to play back one after the other, as long as someone is near the sensor.

please let me know your thoughts/tips/issues!

Many Thanks
Twogan

For my current project I would like to do away with the PC and have the arduino trigering a standalone audio playback board, is this possible ?

Lady Ada has a wave shield that might be useful.

I SWEAR by these:
http://www.mdfly.com/index.php?main_page=product_info&cPath=9_53&products_id=284

Absolutely 100% the cheapest way to play audio using an Arduino.

Here is the REAL datasheet (the one on mdfly is actually just a quick reference)
http://www.thaieasyelec.net/archives/Manual/TDB380%20datasheet%20V2[1].0%20.pdf

I've had good luck with the mp3 trigger from Sparkfun, very easy to use:

Many thanks for all your help.

I shall look into these links and see what will work best...

Thank you
Twogan

"I SWEAR by these:
http://www.mdfly.com/index.php?main_page=product_info&cPath=9_53&products_id=284

Absolutely 100% the cheapest way to play audio using an Arduino."

Too bad they are sold out - replacement looks to be $20 more.

Yes these look perfect.

Can anybody help me with hooking this up to Arduino ?

For my last project I used an SRF04 sensor and used the data to control the pitch of an oscillator in processing.

Now I want to to trigger an Mp3 when someone comes within 2m of my sensor. Then, if the person has left the area stop the playback. When the next person comes within range play the next mp3...

Without the PC involved I am a bit stuck on how this all goes together. Basically how to hook the Mp3 trigger to the Arduino, and how to make Arduino convert distance data from the sensor into playback commands for the trigger?

Sorry to be such a newbie. If someone could point me in the right direction to learn how to do this it would be greatly appreciated.

Many Many Thanks
Twogan

I used this sharp distance sensor http://sharp-world.com/products/device/lineup/data/pdf/datasheet/gp2y0a21yk_e.pdf (Adafruit) to do something similar. I was a little nerdy about it: I used the Vout vs Dist chart in the datasheet, plugged the x/y values in a graphing calculator and determined the best fit line, then coded the output voltage into the "best fit" equation to find the distance.

An easier way would be to measure a distance, say 5 meters in .5 meter increments and measure the output at .5m, 1m, 1.5m, 2m, etc.

What mp3 player did you end up buying? If it's the mp3 Trigger (Spark Fun) the set up is pretty easy. Connect your Vcc, grn, and the RX and TX to Arduino and use serial commands to the trigger. Their datasheet explains all the commands.

I am looking at buying this, the rogue rmp3 shield:

http://www.active-robots.com/products/accessories/rmp3-playback-module.shtml

I want to use this with my arduino UNO and SRF 05 ultrasound sensor. I will be using the arduino to read the data from the SRF 05 and convert it to commands for the Rmp3....Does that sound reasonable ?

Many thanks
Twogan

Sure. Lot of people have had good results with that unit.

CrossRoads:
"I SWEAR by these:
http://www.mdfly.com/index.php?main_page=product_info&cPath=9_53&products_id=284

Absolutely 100% the cheapest way to play audio using an Arduino."

Too bad they are sold out - replacement looks to be $20 more.

Worth noting that these are back in stock.

Yes they are - I just received 1 each of these 3 SD/MP3 units, looking forward to playing with them at some point.
http://www.mdfly.com/index.php?main_page=index&cPath=9_53