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Robotics Science

Robot Bat With Echolocation 159

productdose.com writes "A robotic bat head that can emit and detect ultrasound in the band of frequencies used by the world's bats will give echolocation research a huge boost. Sonar in water is a mature field, but sonar in air is far less advanced. Whenever a robot team wants to build an autonomous robot they look at sonar first, but they quickly run into problems due to the simple nature of commercial sonar systems, and switch to vision or laser-ranging. The IST project CIRCE hopes that the research they can now do with the robotic bat will lead to more sophisticated sonar systems being used for robot navigation and other applications."
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Robot Bat With Echolocation

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  • by cryptoz ( 878581 ) <jns@jacobsheehy.com> on Wednesday August 24, 2005 @11:57PM (#13395155) Homepage Journal
    It collects information about its surroundings, evaluates it, and then discards the data in favour of running into un-seen objects.
  • by TripMaster Monkey ( 862126 ) * on Wednesday August 24, 2005 @11:58PM (#13395157)

    I saw this one on Loony Tunes...the robot bat is dressed up as an attractive female bat, and lures the lovestruck male bat offscreen, where it then explodes, charring the male bat most humourously.

    At least that's the way I remember it. Stupid closed-head injury...
  • by Gertlex ( 722812 )
    I swear, I haven't heard that word since elementary school... After hearing about if for a few years, no one gives a damn about how bats get around.
    • Well, except for people like submariners and pilots - sonar and radar are basically just echolocation.

      Sonar in particular, of course, but radar is just echo-location using radio waves instead of sound waves.
  • Is is is...there there there...anyone anyone anyone...in in in....there there there?
    • Make it right! (Score:3, Informative)

      by PaulBu ( 473180 )
      For all the old Pink Floyd fans -- it's "ANYBODY", not "ANYONE"! ;-)

      Paul B.
  • wrong direction? (Score:5, Insightful)

    by Pr0xY ( 526811 ) on Thursday August 25, 2005 @12:12AM (#13395229)
    i think that these researchers are likely going in the wrong direction. The way I see it, the main problem with things like sonar isn't lack of signals or information. It's processing that information and coming up with useful data. The impressive thing about bats is that they can use the data they resieve meaningfully, not that they can recieve it. once they start writing software that can accurately map a 3d landscape on sonar alone, i'll be more impressed. proxy
    • The bigger problem with the processing is that echolocation requires 2 organs. A mouth to send the signal and an ear to receive. Sight for example, only requires eyes alone to see.

      • Re:wrong direction? (Score:2, Interesting)

        by theapodan ( 737488 )
        You yourself reveal that you need "eyes" to see, that is, you need 2 of them. Without mutiple eyes, you can't establish a range to anything.

        And why exactly is this a problem? Are you saying that researchers couldn't successfully sync send and receive information?

        As a fisherman, I can tell you that bats are amazing, they often chase my bug around as I false cast.

        If you're interested in bats, I recommend you get a membership with Bats Conservation International http://www.batcon.org/ [batcon.org] For only $30 you can b
        • Without mutiple eyes, you can't establish a range to anything.

          Yes you can, it's just a bit slower and more complicated. * You can move a single eye and use the parallax effect to gauge distance. * You can use information from the focusing system to gauge relative and, if you're good, absolute distances. * The expert system in your brain can tell from the size of an object how far it is away.

    • Re:wrong direction? (Score:4, Informative)

      by jcr ( 53032 ) <jcr@@@mac...com> on Thursday August 25, 2005 @12:31AM (#13395308) Journal
      Well, you gotta start somewhere, and you need a sensor before you can synthesize a 3D model.

      • Actually, you need more than one sensor before you can synthesize a 3D model... and because in echolocation, the sending sensor is not the same as receving sensor, you really need 4 sensors total.

        For light/video sensors, you'd need 2 cameras/lasers, plus you'd gain the ability to use edges and colors to identify meaningful objects...

        • What are you talking about? You only need one sonar sensor to get distance to an object. You can do this just by taking the time the sound takes to come back, halving it and then multiplying it by 340. It's not an eye! (On another note, the sender is not a "sensor" it's a "sender" or rather a "pinger".)
          • I think that he means "two sensors in order to triangulate" etc.

            There was a bit of confusion between sensor and emitter though. *grin*

            Basically, it needs one sender and two receivers/sensors in order to triangulate accurately. Yes, it could get by with one sender and one receiver, but then it would need time to establish a baseline in order to triangulate from send/receive1to send/receive2 - which is made harder when the target isn't static either.
            • Please read my post again. There's no need or reason to triangulate since you can find the distance to an object by timing the pings.
              • Please read my reply again. If you're trying to locate a moving item (whether through your own movement or through the item's movement) then it's best to be able to continually triangulate the distance, rather than just timing the response.

                Hence why bats (and most animals) have multiple receptors (eyes, ears, etc.) when distance/triangulation is a factor.
        • Re:wrong direction? (Score:3, Interesting)

          by TapeCutter ( 624760 )
          "and because in echolocation, the sending sensor is not the same as receving sensor, you really need 4 sensors total."

          Rubbish, a bat can catch a moth ("meaningfull object") in flight ("3D model"). It can do this in total darkness using two sensors and an emitter, it's the same principle as a robot carrying it's own light source in the dark.
    • You are right, receiving a signal is not enough. You need to receive the right signal and then process it in the right way. The question is where to process. Traditionally, simple receivers were used and sophisticated processing performed afterwards was then supposed to get all the information from their output. That never worked. What we learn from bats is that the processing has to start early on, i.e., what signal ("sonar ping") to use, how to spread its energy in the environment, where to point the ear
    • Re:wrong direction? (Score:3, Informative)

      by mbrx ( 525713 )
      It does not sound like you have had very much hands on experience with sonars within robotics. The current state of commercially available sonars (in the air) provides a single range measurement for a cone (usually ca. 30 degrees, but sometimes much smaller). This range measurement is *very* unreliable since it only gives the distance to one point (usually the closest) within this cone and only under the rights circumstances (depending on the material, the angle towards sonar etc.). The biggest problem with
    • i think that these researchers are likely going in the wrong direction.

      Yes, but once they get the kinks ironed out in their echolocation, they will be able to go in the right direction.

  • by xmas2003 ( 739875 ) * on Thursday August 25, 2005 @12:18AM (#13395250) Homepage
    I've had six bats show up in my house [komar.org] over the years (including one in the kitchen sink - good thing my wife didn't see that one) ... while I like 'em for the insect/mosquito eating, I prefer them outside rather than swooping around inside my house ...

    BTW, that URL shows me using a pair of screen windows to "fend" one off (I was only armed with a frisbee) - I figured that would provide a pretty good radar return as "solid" surface.

  • I wonder.. (Score:5, Insightful)

    by jcr ( 53032 ) <jcr@@@mac...com> on Thursday August 25, 2005 @12:28AM (#13395289) Journal
    If any biologists are reading this, I wonder if any other terrestrial nocturnal animals use echolocation? I know that some birds (owls in particular) are very good in low-light conditions, do any of them navigate with sound as well?


    • Re:I wonder.. (Score:3, Informative)

      by Eightyford ( 893696 )
      Someone please correct me if I'm wrong; but I believe that moths actually have a natural "radar detector" for sensing their predator's (bats) pings.

      Heh, is pings still the correct word when it's for sonar?
      • where do you think the word came from?
      • Re:I wonder.. (Score:5, Interesting)

        by FleaPlus ( 6935 ) on Thursday August 25, 2005 @01:28AM (#13395511) Journal
        Someone please correct me if I'm wrong; but I believe that moths actually have a natural "radar detector" for sensing their predator's (bats) pings.

        Yup, although it's a purely passive system. There's a fairly extensive overview [uiuc.edu] of how moths detect bats' echolocation pulses. The behavior is kind of interesting... If the moth hears a weak sound (indicating the bat is far away), the moths will just turn around and fly away. If the sound is moderate, the moth will start looping around or stop flapping its wings and flutter down like a leaf. If the sound is really loud, indicating that the moth has a few milliseconds before it becomes bat food, the moth will suddenly fold its wings in and dive down as fast as it can.

        One of my profs mentioned that if you make really high-pitched noises around moths, you can initiate the various evasive maneuvers. I can't remember how to make the noise... maybe something like rubbing aluminum foil together could do it.

        There's also a similar page on the neuroethology of bat echolocation [uiuc.edu].
        • ... maybe something like rubbing aluminum foil together could do it. So if I rub tinfoil together moths will fall from the sky...or is this a "pulled-from-my-ass-and-you'll-just-look-like-a-fo ol-if-you try-it" type example?
          Just curious.
          'Cause I got plenty of foil and some time on my hands.
          • So if I rub tinfoil together moths will fall from the sky...

            Yep. And if you bang a couple of sticks together while hiking, it keeps away the mountain lions.
          • So if I rub tinfoil together moths will fall from the sky...or is this a pulled-from-my-ass-and-you'll-just-look-like-a-fo ol-if-you try-it" type example?

            A little of both... more like a can't-exactly-remember-what-professor-said-but-tin foil-sounds-about-right example. :)

            Although nothing seems to show up on google...
    • A few terrestrial animals other than bats use sonar. An example is the Oilbird (Steatornis caripensis) in South America as well as some swiftlets. Owls also use sound to track down their prey, but they do not produce "sonar pings" them themselves. Instead, the listen to sounds that the pre-produces.
    • Re:I wonder.. (Score:1, Offtopic)

      by Walt Dismal ( 534799 )
      Hopefully this isn't too far off-topic, but - why did Batman never incorporate sonar or electronic sensors in his costume? It would help to have some way to detect things in the dark. And he has the ears already. Seems to me to be a natural.
    • Some owl species (particularly nocturnal ones) have one ear higher than the other, so that they can locate the position of a sound vertically as well as horizontally, due to one ear receiving the just sound before the other does.
    • Flying dolphins use echo location very successfully. They only hunt at night and have learned to avoid human contact at all costs ( which is why you have probably never heard of them ) which is some indication of just how good their echo location must be.
    • Some birds do, after a quick google:

      http://encarta.msn.com/encyclopedia_761552516/Bird .html#p191 [msn.com]

      Also remember that insectiverous bats, ie the small ones, evolved* there ability to ecolocate seperately from the unrelated mega bats, mostly fruitbats.

    • Re:I wonder.. (Score:2, Interesting)

      by asterisk_man ( 18358 )
      Don't forget about human echolocation [wikipedia.org]
  • by Vombatus ( 777631 ) on Thursday August 25, 2005 @12:31AM (#13395307)
    Its just not cricket.
  • by blackcoot ( 124938 ) on Thursday August 25, 2005 @12:43AM (#13395355)
    sonar does, indeed, suck. and not in the fun way.

    why, you ask?

    1) it's an active sensing modality (unless you've got a really bigass submarine with phased passive sonar arrays and a huge baseline, you're not going to get any range data out of the thing passively).

    2) it's really damn tricky to process properly. sonar tends to fail in littoral waters because of multipath, echos, etc. in man made environments, the multipath + echo issues become really damn hard to solve without some good 3D models of the world around you (but if you can build those models, why bother with the sonar?)

    3) signal to noise ratios are killer. this coupled with the innate difficulties in processing sonar /anyways/ pretty much seal the deal.

    4) compared to other sensing modalities for non-aquatic environments, sonar just can't compete. if you have a single, calibrated camera and know its pose relative to the ground, you can calculate the exact position of any object on the ground. (more generally: if you know the pose of the camera relative to a known plane, you can precisely determine the position of any point on that plane up to what the camera's resolution will allow) if you have a stereo head, things get a lot more interesting (you can combine stereo imaging with structure from motion and get some highly accurate ranges).

    that all said, if this research can solve those problems, i know i will gladly use their sonar / echolocation stuff (it can't be blinded by the sun, unlike ladars, although both will have major issues with rain).
    • As a general comment, I would like to remind you that bats are an "existence proof" for the power of in-air sonar. These animals are active in 3-dimensional space, they are versatile, often predatory, and they can achieve all with biosonar as a sufficent far sense. As to your specific points:
      1) sonar can be used both in active and passive mode. You are correct that range information is not easily obtained in the latter case, but range is not everything and you can learn a lot form listening to what is goi
      • 1) i try to avoid active sensing wherever possible. sonar (and, i suspect, ultrasonics too) have the same problems that gps has: multiple returns. there are tricks you can use to try to limit those (phase modulation, frequence modulation, and so on), the problem is that in sonar those problems are only exacerbated by the incredibly complex geometry to man made environments. as i pointed out, sonar in shallow waters has this same problem.

        there is also a question of what happens when you attempt to build a te
    • There is more than just range or location of objects to map. You could possibly map the density of objects, or even dynamic media like beer, dense air in storms, fluctuating seawater or even semen salinity, or the complex atmospheres on other planets/planetoids using echo location derived technologies. These capabilities come from the fact that sound is a different form of energy wave than EM waves. Sound is a compression of the medium, like air, at certain times, like 50 times per second (the brown nois
    • A Dolphin (or Porpoise) has a large head filled with fat and nerves. The dimensional space receives echoes. I believe the Dolphin keeps all the sound in 3 dimensions -- never detecting it in two. The nerves within the fat model the wave form shapes directly to the brain.

      I've always felt that we should be using ultrasound devices to communicate with dolphins, rather than trying to send them recordings. We think it is the same sound, but our sound comes out of a speaker which is two-dimensional, while the dol
  • Question: is it waterproof? Man, I can't wait to take one of these babies in the pool to play marco polo! Then we'll FINALLY get to have a proper showdown between man and machine! USA! USA!
  • by Anonymous Coward

    One project partner developed a broadband transducer that could both convert acoustical energy to electrical energy and electrical to acoustical across the 20 to 200 kHz spectrum.

    Now all we need to do is train bats to repeat what they hear, and we will have wireless TCP/IP by bat.
  • While this in interesting research, I can't help wonder if they are taking into account the possible negative effects this might have on real bats. Could too much noise confuse them? As I've understood, bats can cooperate in order not to create too much noise. One chirps, many listen to the result.

    I doubt a robot would show the same courtesy...
    • First of all, it is still not fully clear if bats take special actions to avoid "jamming" each other. Ultrasound doesn't carry far (due to absorption) and ultrasonic emissions by bats (and the CIRCE head) are pretty directional, i.e., sound goes mostly into one direction. So the space that is "jammed" by a bat (or a robot) is really small. In the temporal domain, there are a lot of pauses, too. So one sonar system (bat or robot) really influences only a small volume for short time intervals, which should no
      • This is something that has interested me for some time - I have always wondered how they avoid jamming each other. Having stumbled into a small disused building full of sleeping bats and accidentally disturbed (hundreds of) them, I can safely say that they do sometimes flock together in large numbers. This would mean that in this situation, if they only relied on direction to "filter" out their own noise, in a flock like this they would be effectively blinded by each other ( perhaps they were! it wasn't d
        • There are certainly situations with so many bats so close to each other that they will likely jam each other, e.g. in a large colony. However, in most of these situations, the bats are "at home", so they don't need and - as anecdotal evidence suggests - probably don't read their sonar.

          Since bat sonar is directional on the emission and reception side, as well as - for "resonably" specular targets - on the reflection side, is range-limited by absorption, and - as you point out correctly - there is a time w

  • ... the morphing wing gull plane [slashdot.org] from a few posts back. It could become a serious nuisance worthy of commercial or military exploit.
  • by JonXP ( 850946 ) on Thursday August 25, 2005 @01:12AM (#13395457)
    I, for one, welcome our new robotic homerun hitting overlords.
  • I applaud their efforts to increase human knowledge regarding SONAR technologies. There are quite a few potential benefits that may arise.

    One would hope, however, that we don't start relying too much on SONAR becuase it appears to be of limited functionality, can potentially cause noise pollution, and even alter the migration patters of bats themselves ;) Either that or maybe it would drive dogs and cats crazy.

    Well, whatever the case, I'm quite curious to see how far they go. I mean really, the te
    • One would hope, however, that we don't start relying too much on SONAR becuase it appears to be of limited functionality, can potentially cause noise pollution, and even alter the migration patters of bats themselves ;) Either that or maybe it would drive dogs and cats crazy.

      Don't worry about the noise pollution or the effect on other animals. Ultrasound has a very limited range in air. Because of this, bats can cope with other bats being around and probably don't even need to take any special precauti

  • ...tell me these people have been responsible enough to also design a robotic tennis racket, in case that damn bat finds its way into my house?
  • It all sounds well and good now, but the generations that come after us and suffer the scorched earth will curse us for the invention that brought forth the legions of robotic vampires.

    Forgive us, for we know not what we hath wrought.

  • by The Master Control P ( 655590 ) <ejkeever@nerds[ ]k.com ['hac' in gap]> on Thursday August 25, 2005 @02:52AM (#13395738)
    I remember reading a few years ago about a new sonar-like system being tested by the military to locate snipers. A soldier would carry a microphone, recording the sounds as he went. When a gun was test fired, the information was fed into a computer which computationally tracked the motion of the sound waves through a test course back to the point of origin.

    It's a very promising system (Someone shoots at you, your eyepiece HUD immediately tells you where he is), but it was totally impractical. IIRC, they needed to have a prebuilt 3-d model of the test range for the program to backtrace the bullet. It also took the simulation hours to backtrace one bullet when run on a supercomputer. The computing power will soon be no problem. The hard part will be to generate a sufficiently accurate 3-d model of downtown Baghdad...

    It sounds as if some of the things they are researching here (preprocessing input/output) might have some application. Don't know what became of that sound-backtrace project, though.
    • I think they were using some of this "back trace" with gang violence in test areas -- I believe it was even used on that famous sniper (name escapes me, Michael Jackson and TDK maniac have numbed the brain -- I've quit the news, I suppose that was the goal).

      There are three components available; infra-red satellite detection (muzzle flash), detecting the bang (I suppose you record all the time, and a sufficient bang says to "mark and keep data"), and location. I was reading that they'd put multiple Mics in a
  • Call me crazy...

    but isn't "Sonar in Air" called "radar"?

    and don't we pretty much have some pretty sophisticated radar systems out there?

    or are we talking about some horrible shrieking sounds in the audible spectrum to make this happen?
    • Re:sonar in air... (Score:3, Informative)

      by adrianmonk ( 890071 )
      Call me crazy... but isn't "Sonar in Air" called "radar"?

      Not exactly. Sonar ("SOund Navigation And Ranging") uses sound but radar ("RAdio Detection And Ranging") uses radio.

    • Radar uses electromagnetic waves, in-air sonar uses ultrasound. Ultrasound frequencies are by definition above the audible spectrum, so you don't hear them.
  • by BlackHat ( 67036 ) <Tahkcalb@[ ]il.com ['gma' in gap]> on Thursday August 25, 2005 @03:55AM (#13395850) Journal
    Or more correctly Cillia.

    A single (ignore the pair for direction for a moment) detector element is not going to get any accurate (3D) results, no matter how good the post processing.

    Also the shape of the ear is minor in comparison to the "array" of information from the messages the individual hairs(cillia) send to the brain. Not saying they're wasting their time, just that it will likely be sub-optimal by design. Also I'd bet the hair pattern(layout) is more important than the over all shape too. But then IANAB* so what do I know.

    (*I Am Not A Bat)
    • You are correct in pointing out that a single sensor cannot give "good" 3d results; they may be "accurate", but not unambiguous (all points on the surface of a prolate spheroid correspond to the same mouth-to-ear time-of-flight).
      The array information from the individual cilia is - in the first place - exclusively a frequency-domain information, because the inner ear splits the incoming signal into its frequency components. The earshape can add a spatial dimension to this, because it can cause the ear to b
      • The earshape can add a spatial dimension to this, because it can cause the ear to be sensitive in different directions for different frequencies. So it is not a question of "either or", ear shapes and frequency analysis by the cilia work together.

        Thanks for pointing that out, I had not fully thought it out. So FFT-like post processing step(s) would, or could, be effective in simulating most of the function of the cillia. Cool, thanks. Good work so far, keep at it.
    • With one hair per frequency. Make that one frequency per hair.

      Hair damaged? you can't hear that frequency. Lots of hairs damaged? You're deaf, even though the actual receiving equipment may be fine. You can no longer receive input from that hair which makes you deaf to roughly that frequency, +- some percentage around it.

      I'm sure that it would be possible to 'grow' silicon cilia to fit into a 'tuned pipe' to give ears to our computers. Then the fun comes with processing.

      Detecting direction is simple and can
  • Lets get this straighten out.. they made cyborg bats with friggin' radar beams attached to their heads!!
  • With the demise of real nature, and cutting cost on the remaining nature, the following proposals are being made:
    In cities replace real gras with fake gras, same for flowers and trees (who cares that the real versions produce oxygen, and reduce polution in several ways)
    Since plastic trees and flowers are less likely to sustain life, other forms of life will be replaced too. The research sofar has the following:
    Robotic dog
    Robotic cat
    Head of bat (hey, Do you want to have them flying around?)
    Some fake co
  • Get back to me when it can fly.

    A head that can ecolocate is nothing - we've been using sonar and radar for years.
  • To Robot Dracula! The vorld vill tremble! He vill suck your blood! Problem is, when he gets too close to a Window in the daytime he gets a BSOD
  • I was just curious if this technology would be harmful to bats? Would it make them confused or crash into things?

    Isn't that the case with sonar where it harms dolphins somehows?
  • by Dareth ( 47614 ) on Thursday August 25, 2005 @09:12AM (#13396633)
    ... so does wearing a tinfoil hat help protect you from these robotic bats?

    Or does tinfoil help "bounce" the sounds back and give them a better target!?!

    It is getting so hard to be paranoid these days.
  • by Anonymous Coward
    Not sure If I'm for or against this.
    On the one hand, bats are scary.
    And yet everyone likes a little head.
  • Whenever a robot team wants to build an autonomous robot they look at sonar first, but they quickly run into problems due to the simple nature of commercial sonar systems

    What do they base that on? That's just ridiculous. I admit, sonar is a very common choice, but he says it as if robot builders blindly go into sonar first thing always.

    I think maybe he went into it without doing any research because he's clearly not aware of some of the impressive prior work done in the field. He's not the first to use ult

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