Arduino Forum

Using Arduino => Audio => Topic started by: Celteek on Mar 29, 2011, 07:08 pm

Title: Whistle detection
Post by: Celteek on Mar 29, 2011, 07:08 pm
Hello everyone!

I'm working on a robotic project, and I'd like my robot to detect when I whistle. But I'm not that good in electronics... :( Do you know how I can do that? I thought of amplifying the sound with an amplificator and then look for the frequency using the arduino. But is ths possible?
Maybe I should use a frequency-voltage converter? But I want the electronic to be as simple as possible...
Thanks a lot for your help! :)

(Remember I'm a noob :D)
Title: Re: Whistle detection
Post by: RuggedCircuits on Mar 29, 2011, 07:19 pm
A simple way to do it is with a small microphone and amplifier circuit, like the one on our Gadget Shield (http://ruggedcircuits.com/html/gadget_shield.html) or a stand-alone module like this one (http://www.sparkfun.com/products/9964).

The question is are you just looking for a sound/no-sound decision or are you actually trying to measure the frequency of the whistle and only want to respond to a certain whistle frequency? Selecting a single frequency is a little bit more work, though there have been some Arduino FFT projects recently that can help with this (searching for "Arduino FFT" will give lots of results).

--
The Rugged Motor Driver (http://ruggedcircuits.com/html/rugged_motor_driver.html): two H-bridges, more power than an L298, fully protected
Title: Re: Whistle detection
Post by: Big Oil on Mar 29, 2011, 07:46 pm
FYI I tried to hack a small 'lost car-key finder' device that would beep when you whistle, but the thing broke before I could get it to talk to the Arduino. 
Title: Re: Whistle detection
Post by: Grumpy_Mike on Mar 30, 2011, 07:19 pm
There is a chip that will do the whistle detection for you.
The UM3763 contains a signal amplifier and frequency detector and is housed in a small 8 pin package.

Other chips are here:-
http://uk.farnell.com/jsp/search/results.jsp?N=500006+1004414&Ntk=gensearch_001&Ntt=tone+decoder&Ntx=mode+matchallpartial&isGoback=false&displaytext=&isRedirect=false (http://uk.farnell.com/jsp/search/results.jsp?N=500006+1004414&Ntk=gensearch_001&Ntt=tone+decoder&Ntx=mode+matchallpartial&isGoback=false&displaytext=&isRedirect=false)
Title: Re: Whistle detection
Post by: Celteek on Apr 02, 2011, 07:14 pm
Do you think a LM567 can work?
Title: Re: Whistle detection
Post by: Magician on Apr 02, 2011, 07:49 pm
Regular piezo buzzer is a whistle detector due it extra nonlinear frequency response.
Probably, operational amplifier thats all you need to get sensitivity level .
Title: Re: Whistle detection
Post by: Grumpy_Mike on Apr 04, 2011, 02:56 pm
Quote
Do you think a LM567 can work?

Yes that would work.