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[on:]

I'm working on an interactive sculpture project. There will be strings-I want to make it so if someone pulls a string, it will produce a sound.
I am thinking strain gauges are the way to go about doing this so I can have a different output depending on the reading of the gauge.

I've never done a project like this before but I understand the basics. I just need some guidance on what the proper (specific) hardware would be.
Any advice is welcome (when it comes to the programming part as well).

(Also-if I need to give more detail/explanation on my project, just let me know)

[Reply #1 on:]

How are you converting the strain guage output to a 0-5V output that the arduino can then make sound production decisions about?

[Reply #2 on:]

Please do not cross post. Delete the two identical threads you have posted.

[Reply #3 on:]

An alternate approach might be spring-loaded potentiometer, either linear that slides back & forth, or rotary, and pulling on the string moves the pot wiper back & forth.
Can add block & tackle like arrangement to allow for bigger string movement & smaller wiper movement.

[Reply #4 on:]

Another alternative to a traditional strain gauge would be to attach the strings to conductive rubber.  The rubber would be electrically connected as part of a voltage divider from +5 V_DC to ground, with a wire connected between the cord and a constant resistor.  The wire would then connect to an analog input, and when the voltage goes below a threshold (because the rubber's resistance increases as it is stretched) you can have the Arduino signal a WAVE shield, MP3 shield, or other playback device.

[Reply #5 on:]

I'm interested in learning more bout the conductive rubber-I'll look into it.

I guess I'm not really clear on how the reading from whatever sensor part that I use translates into sound [or the steps I need to take to make that happen].

Will I be able to program the WAVE shield/MP3 shield/whatever playback device to have more than one option for the sound output or will it just play back one file repeatedly?

[sorry for all of the questions, just trying to figure things out]

[Reply #6 on:]

I believe you can find a way to play selected files:

http://www.mdfly.com/index.php?main_page=product_info&cPath=9_53&products_id=806

Make a decision about what to play based on sensor readings from the string pulls.

Another option
http://www.roguerobotics.com/products/electronics/rmp3

[Reply #7 on:]

There are basically two ways to make sound with an Arduino.
One is to use tones. 
http://arduino.cc/en/Tutorial/Tone

The other way is to use a shield such as the Wave shield or an MP3 shield.
These shields use an SD card to store files, so you can add as many sound files as you like.
Last year I converted an old radio into an MP3 player. http://arduino.cc/en/Tutorial/Tone

[Reply #8 on:]

A third way is using the Arduino to synthesis the sound from scratch -

http://rcarduino.blogspot.com/2012/08/the-must-build-arduino-project-illutron.html

http://rcarduino.blogspot.com/2012/08/adding-audio-to-arduino-projects.html

http://rcarduino.blogspot.com/2012/09/algorithmic-music-on-arduino.html

http://rcarduino.blogspot.com/2012/10/arduino-modular-synthesizer-part-one.html

Lots of other examples out there as well.

Duane B

rcarduino.blogspot.com

[Reply #9 on:]

Thanks for all of these examples.

Here's a dumb question -- is the WAVE shield able to do everything alone (meaning react to the sensors/whatever I end up using) or is it just an add on that has to go with another board?

[Reply #10 on:]

Just an add on - you need the Uno/whatever below to read the sensors and make decisions about what file to call up for playing.

[Reply #11 on:]

Awesome, I've purchased both pieces.

Any suggestions on speakers??--they need to be fairly small.

[Reply #12 on:]

Define "fairly small" in inches/mm/wattage, etc.

[Reply #13 on:]

I have tested/used some small 1.1" diameter 1.5w/2w max speakers before...

the WaveShiled.. (IMHO) has VERY low volume by default...

I would read up on doing the volume hack for it..

[Reply #14 on:]

This speaker or something similar should work fine.
https://www.sparkfun.com/products/9151