sound Sensor?

[relto]

I plan to build robot that can sense the direction of voice and can turn to that direction.
The problem is how to make 20cm dimention robot can sense the direction of the voice.
please help make my dream come true > <
My Robot look like this


Thank you

[Parmin]

Place three sensors equidistant around your bot.
Measure the time when the sensor receive the required command.
and by triangulations you can "guess" the distance, angular location of the noise.

Problem you may encounter
1. echo of hard surfaces may confuse your logic.
2. ambient noises will confuse the logic - you have to have a good filtering routine for this.
3. willingness to try.. and feedback to the suggestions.

if you just hypothetically ask questions but do not folow up, whoever try to help you may not do the same next time.
goodluck

[relto]

Can it done with small robot 20cm diameter?
I think all sensor will receive at the same time at that distance.

if you just hypothetically ask questions but do not folow up, whoever try to help you may not do the same next time.
goodluck

I plan to do it for last year project but i'm not sure it can be done or not by myself.
I just ask for the probability.

[Parmin]

Definitely can be used on a 20cm robot.
Sound does NOT arrive the same time at that distance.

Consider that you have TWO ears and you CAN figure out where sound came from.

[afreakmachine]

hello!!
try make about 8 AXIS microphone use ADC with your MCU to compare 8 sound source's sound level

[orange]

Microphone Array Robot Sensor

http://www.circuitcellar.com/avr2006/winners/DE/DE_Entries/AT2931.zip

[Hamdi]

Place three sensors equidistant around your bot.
Measure the time when the sensor receive the required command.
and by triangulations you can "guess" the distance, angular location of the noise.

This is almost impossible, you know that the speed of sound at the room temperature on the air is 343m/s, which means in our case, with just 20cm diameter, the ears could be placed at maximum 3.2cm apart, making only a delay time between them at maximum of 9.33us, which requires a check on the sound signals at the minimum speed of 110KHz which only would work in the case of talking from the sides, from the front or back, the clock shall approach infinity, I think your solution is not optimal at all.

I plan to build robot that can sense the direction of voice and can turn to that direction.
The problem is how to make 20cm dimention robot can sense the direction of the voice.

You could use the microphone array measuring the signal strength which would enable you to do a source recognition in the 3D scope.

[solutions]

You are after direction, not ranging. 

Get some very directional microphones (or make them directional by putting them inside some tubing or smal piece of PVC pipe) and set them up on the periphery, more is better.....then head for the highest amplitude mic...in this setup you WANT the microphones close to each other or you will have to correlate (shift in time) the incoming audio to do the amplitude analysis. 

You can get some pretty tiny digital microphones (which allows you to use the digital ports on your microcontroller vs amplifiers and A/D channels) from Akustica http://www.akustica.com/products/digitalmic.asp , but you'll have to make them directional with a sound pipe (maybe as simple as a plastic pipe elbow?).

[Hamdi]

After all, it's measured by amplitude to decide the source direction, not using sound propagation, this is the point I was trying to say.

[Parmin]

This is almost impossible, you know that the speed of sound at the room temperature on the air is 343m/s, which means in our case, with just 20cm diameter, the ears could be placed at maximum 3.2cm apart,

Dude,  I am not sure where you get the 3.2cm figure,
maybe you ought to go back to primary school before opening your yap, pull some moronic math out of your ass
and criticize a post I made almost 2 years ago?

Let me enlighten you a bit,
Unless things has change or you are fully drunk,
 Circumference of a circle is Pi x diameter, in this case, we can round it to 3.14 x 20 cm or about 60.42 cm.

Assuming the sensors are located on the tip of the hemisphere, the equidistance location should be more than 20cm apart.
Surely if you stagger the location on the ball, you will get even larger distance between sensors.

Now, you are quick to point out the delay time of 9.33us and saying that it is way too short to use to measure distances.
Again dude, wake up and smell the coffee.. these days we are using hundred of megahertz microprocessors,
even to the GHz ranges on small boards such as Nano ITX and Pico ITX.
9.33 us is PLENTY!!

I hope you enjoy the reaming and stop being such an ass.


Posted on: March 10, 2010, 11:44:05 23:44 - Automerged

After all, it's measured by amplitude to decide the source direction, not using sound propagation, this is the point I was trying to say.

Again bullshit!
Although amplitude is required to ensure the clarity of the reception,
it is definitely the speed of sound propagation that determine the direction of source.

Go back to school newbie, before you offend more people.

[Hamdi]

Dude,  I am not sure where you get the 3.2cm figure,

You are true here, I made a mistake since my English is too bad, I thought 20cm is circumference and calculated the radius by mistake, but it's a diameter.

it is definitely the speed of sound propagation that determine the direction of source.

But this slightely makes diffrence for the propagation time while in the sides, but not useful at all for the front or back, it's the same as clock shall reach infinity for the same propegation time on both microphones, if three or more microphones are used, it may be became useful, but what about if the transmission is not limited to one clock time which is definetly not limited to that, then you would need to use correlation alogorithms which makes this too complicated and may yeld to huge processing in order to know the start and the end of transmission while recording the transmission in order to correlate it, this is crazy.

maybe you ought to go back to primary school before opening your yap, pull some moronic math out of your ass

I hope you enjoy the reaming and stop being such an ass.

Again bullshit!

I think you deserve being reported to the moderators here, thanks for being so gentle

and criticize a post I made almost 2 years ago?

I don't think there exist a role to prevent replying to a 100 years replay, am I wrong?

Go back to school newbie, before you offend more people.

Stop hanging in your opinions, and being newbie in the forum, doesn't mean newbie in robotics.

The amplitude would diffrentate even with small ranges, wich is easily measure then contered by ADC, then compare and decide!! too easy way to do that.

[pickit2]

for a monent I thought I was in entertainment topic, but then could not see pic of bbarney. so funny

[Hamdi]

I don't know nor can understand the English jokes since it's not my culture, but I believe that pickit2 wants to indicate that he wants not to handle the case of Parmin insulting me.

Unfortunately, I really liked this entire website/forum too much, but this forum is uglier than what I thought.

[pickit2]

but I believe that pickit2 wants to indicate that he wants not to handle the case of Parmin insulting me

Im sorry if you think like that, but here as in the real world, you have to stand up for your self, as you tried to do and failed.
but to post in a near 2 year topic, that original poster must have sorted by now, and then give an answer Parmin and others, pointed out the down side of the solutions given. you only gave Parmin the ammo he needed to shoot your answer down. take care you don't get biten by the ferret if you play with the animals in here.
Also the jokes are to take pressure out of the topic, sorry if you can't see that.

[metal]

You are true here, I made a mistake since my English is too bad, I thought 20cm is circumference and calculated the radius by mistake, but it's a diameter.

3.2cm, as it was meant to be 32cm, or what ever it was meant to be, I don't care. Explain to us Hamdi, how this bad english problem made you write the period ".", or if the error was not the period, then what was the error?

Unfortunately, I really liked this entire website/forum too much, but this forum is uglier than what I thought.

BTW, if you really think that this forum is so ugly, then I can book you one way ticket out of here, what do you think? I will not charge you this time...

You are causing so much troubles and nuisance here (Hope you know, understand, and perceive the concept of DOMESTIC DISTURBANCE), I don't like it at all the way you are behaving, attacking members and moderators. I promise you, you will pay for your stupid actions Try not to make your last move the reason for me banning you, just help your self and try... I have been watching your behavior, and when I write such words in public for someone, then the last episode is so close, so try to extend your staying here, and close your mouth for a while... Stop reporting posts like crazy, you are making us spend more time on your invalid behavior, read the rules again, may be you english becomes better!

Don't reply to my message, I don't want to hear what you want to say!

[Parmin]

I think you deserve being reported to the moderators here, thanks for being so gentle

YOU ATTACK ME FIRST!
Now that I replied, you say that this forum is ugly?
You want to report me? well go bloody ahead YOU MORON!!
The most the forum can do to me is to ban me.
If that happen, you will only get stupider..

I don't give a shit as to whether or not you are an expert in robotic or not.
Your answer is pathetic and simply untrue.
If you don't even know the difference in usages for velocity VS amplitude,
then you are a lost case, I wont event bother to argue with you.

Go back to school newbie, you are pathetic.

[solutions]

Settle down, children. We have cultural clashes here that don't call for banning anybody, IMO

"Bullshit" is one of the highest forms of challenge to a position of certainty.... in western culture.  It is not profane, but a proclamation that your public confidence, or proclamation, is either a bluff, uninformed, or fraudulent.  You could even say that it is an engineering term.

The appropriate response to being called out in this manner is to either concede the call as valid (which is actually safe because everyone knows someone in the group is brave enough to out the truth) to come up with an answer that makes the proclaimer of "Bullshit" feel like what's known as "feeling like an ass" - without actually calling him one.

Calling him one is ad hominem, which should be discouraged.  Attacking ones facts should be open season.

Don't confuse the two or inadvertently cross the line.

My $0.02 (another westernism)

[Hamdi]

First of all, to make things clear, I made a mistake in my calculations, 20cm thought as the circumference then calculated radius rather than diameter. Although I tried to get the diameter, it was already given, but as I read measurements using another language, I messed the meanings of them, and this is not an excuse, I made a mistake and I admit that.

But, it doesn't matter if I did mistake or not, we could discuss that, but to turn the discussion into a personal issue, this is my problem here.

Let us agree in this, I was talking about propagation, sound, and circumference, and you could say: "this is crazy", but please don't say: "you are crazy", did you got my point??

Using the terms that I were trying to report to moderators really hurt people, it's not a discussion like that, it's an insult. and that's why I thought this forum is not really as I thought, tries to discuss science, it seems (at least to me) its members trying to insult human beings, that's why I'm making all this babel.

I hope all people here try to use a better ways to express their feelings, to act like gentle men/women, to stay away from this ugly words, and to keep talking about the same subject, not to switch subjects into the creators of the subjects.

Let us make this website like IEEE's website, Interested only in science, not in the various usages of bad words!! Even you say it's not that ugly this words are, I can't bear with it being used in such a website, and that's why I contacted moderators, because I believe they share the same love or more for this forum, and if they do, then they would like to erase this words from here.

I hope that you got my point so far, I'm not here to make instructions, nor to make people upset, but also I'm not here to search for some one insulting me as well.

Why not to make this website like heaven, that doesn't uses dirty words, that doesn't try to insult people, it only discuss ideas and thoughts?!!!

Also the jokes are to take pressure out of the topic, sorry if you can't see that.

Thank you for your kindness! it's not a temporary pressure, it's a permanent clash

Don't reply to my message, I don't want to hear what you want to say!

I can't keep silent Sir/Madam while you think that I'm attacking members and moderators. Please bear with me until getting my ideas clear to all.

BTW, if you really think that this forum is so ugly, then I can book you one way ticket out of here, what do you think? I will not charge you this time...

I don't want to travel away from here until you got my point, then you have your own decision to make me in or out!!

YOU ATTACK ME FIRST!

No I did not, I replied saying "This is almost impossible", "I think your solution is not optimal at all" and "this is crazy", not saying "You are impossible", "I think you're not optimal at all" and "you're crazy"

But look at your replies that I already quoted, it sounds like you hold me a grudge!! did you got my point? I'm not here to hurt you, nor to show that you are idiot (like what you did with me), I'm trying to discuss things, I didn't said you are totally wrong, I said your idea is not optimal, if you can't accept even discussing ideas, how could you discuss other people being "ass" or what ever words you use to express how hate you do me??

Settle down, children. We have cultural clashes here that don't call for banning anybody, IMO

Thank you for your reply, but what I want to say is that I hope that what ever we are discussing, it's related to your thoughts, not yourself, and if someone is not agree with you, he shall discuss that, saying your ideas is wrong, but saying you are wrong is not acceptable (at least by me), using some words like "go back to primary school", "such an ass", "bullshit" or "MORON" means this is not talking about the subject we are talking about, it's talking about me as the subject instead, and that's what no one (at least from my culture) would accept.

[Ichan]

Relax guys, relax....

Anyway Hamdi, you make me nervous - your English is much better than me.

-ichan

[Wizpic]

This tpoic is getting way out of hand and it
 MUST BE STOPPED RIGHT NOW

Topic locked
And do not start another topic about this or try to continue it in another topic

Us moderators try to be fair and understanding, and we will deal with any members that break the rules or cause trouble so you lot count yourselves lucky no one got warned or muted 
Wizpic