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Robot Bat With Echolocation

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."

32 of 159 comments (clear)

  1. So, what does your robot do? by cryptoz · · Score: 5, Funny

    It collects information about its surroundings, evaluates it, and then discards the data in favour of running into un-seen objects.

  2. I remember this one... by TripMaster+Monkey · · Score: 4, Funny


    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...

    --
    ____

    ~ |rip/\/\aster /\/\onkey

  3. Echolocation by Gertlex · · Score: 2, Funny

    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.

  4. Echo, echo... by Joey+Patterson · · Score: 2, Funny

    Is is is...there there there...anyone anyone anyone...in in in....there there there?

  5. Make it right! by PaulBu · · Score: 2, Informative

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

    Paul B.

  6. wrong direction? by Pr0xY · · Score: 5, Insightful

    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

    1. Re:wrong direction? by jcr · · Score: 3, Informative

      Well, you gotta start somewhere, and you need a sensor before you can synthesize a 3D model.

      -jcr

      --
      The only title of honor that a tyrant can grant is "Enemy of the State."
    2. Re:wrong direction? by rolfmueller · · Score: 2, Interesting

      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 in the environment and for which sounds from where to be sensitive. Remember that by virtue of the data processing lemma in information theory, you can only throw information away when processing sensor output. However, if you influence the process where information is created, you have control over what information comes into the system.

      Producing an accurate 3d landscape representation is probably not the way to go either. If you design a robot, this is rarely what you want. A robot has to navigate around and to attain some goals, so it should extract from its sensors exactly the information that it needs to do that. 3d Map are unnecessary detours in most cases, because you still have to interprete the map then.

    3. Re:wrong direction? by theapodan · · Score: 2, Interesting

      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/ For only $30 you can be a member. And helping furry creatures is good for the soul.

    4. Re:wrong direction? by TapeCutter · · Score: 2, Interesting

      "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.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    5. Re:wrong direction? by mbrx · · Score: 3, Informative

      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 these sensors is the low angular resolution and unreliability. Nonetheless the state of the art in, for instance, map building manages to construct some surprisingly accurate maps, to navigate in indoor environments etc. To say that the data isn't _used_ well enough is not an accurate description of the problem. The problem rather lies in the sensors and in the signal processing (computing eg. range data). Oh, and also: if you are interested in robotics make sure to take a look at Player/Stage http://playerstage.sourceforge.net/ which is an opensource implementation of drivers for various commercial robots as well as some controll functionalities, simulators etc.

  7. Just don't have the robot bat fly into my house .. by xmas2003 · · Score: 4, Interesting
    I've had six bats show up in my house 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.

    --
    Hulk SMASH Celiac Disease
  8. I wonder.. by jcr · · Score: 4, Insightful

    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?

    -jcr

    --
    The only title of honor that a tyrant can grant is "Enemy of the State."
    1. Re:I wonder.. by Eightyford · · Score: 2, Informative

      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?

    2. Re:I wonder.. by FleaPlus · · Score: 5, Interesting

      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 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.

    3. Re:I wonder.. by asterisk_man · · Score: 2, Interesting

      Don't forget about human echolocation

  9. Robot bats?? by Vombatus · · Score: 4, Funny

    Its just not cricket.

    --
    This sig is intentionally blank
  10. Re:What the fuck by nzkbuk · · Score: 5, Interesting

    Who says the visual spectrum of the EM band is the best way to interperit the world.

    Wet, the only way to be sure if something is wet is to touch it (or put some other sensor into or onto it. I've seen lots of thengs that "looked" wet but it was just the glossy type look.

    Soft, Sound is a MUCH better indicator for softness than sight. We've learnt that certain things look hard and soft. it's no measure if they are or not. You can make a barbell out of foam and with a good paint job it will look exactly like the real thing until you touch it. it won't however sound like a solid piece of metal. the returning sound will be muted / distorted.

    Alive, see soft. I've seen people make realistic looking things on the beach. They could never have been alive, but they can look it.

    Sorry bot the 3 examples you've used would have to be the worst 3. A more likely reason we have 2 eyes is we were origionally predators. We notice movement and distance well. It helps us hunt. As sight is effectivly passive (we don't have to shine light out of our eyes) it allows us to be more stealthy.
    While bats use sonar, it's an active sensor. you have to keep making sound to use it. If more predatory animals used sonar to hunt, then more hunted animals would be able to detect it.

    Back on topic however, If naval sonar is so advanced, why is atmospheric sonar so lacking ?
    isn't it essentually a timing thing (sound travels faster in denser mediums like water than air). put a different emitter on and then adjust the timings.

    Oh and if you're just sitting down, not moving etc can anyone see that you're drunk ?

  11. i do agree with one thing by blackcoot · · Score: 5, Interesting

    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).

    1. Re:i do agree with one thing by rolfmueller · · Score: 2, Interesting

      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 going on around you. Using an active sense and bringing your own energy sources can also be an advantage, if there are none around.
      2) sonar can be used for many other things than building 3d models. You may for instance tell what kind of environment you are in, whether you are likely to collide with an obstacle, etc., all without a 3d map.
      3) Ultrasound in air has a limited range due to absorption and spreading losses. However, when operating at a close range (say within 10-15 meters) you can get excellent signal-to-noise ratios (say 40 to 80 dB). If you don't move too fast, such a range should do.
      4) The question is what you want to do. Sonar can easily outperform a camera, if there is no light, or if the air is filled with thick smoke, in murmky water, and so on. Other issues are the cost of processing, data storage, and so on. Your fance stereo processing isn't exactly cheap computationally, so far a small consumer electronics product, sonar may offer a much better deal, for instance.

  12. Holy Cow Batman!! We're on the batnet!! by Anonymous Coward · · Score: 2, Funny

    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.
  13. I for one... by JonXP · · Score: 4, Funny

    I, for one, welcome our new robotic homerun hitting overlords.

  14. Re:Ultrasound band saturation? by rolfmueller · · Score: 2, Informative

    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 not hamper others all that much.

  15. Re:Why in the world.... by rolfmueller · · Score: 2, Interesting
    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 precautions.
    the technology is only going to be good at things that reflect sound.
    In air, all "usual" (i.e., not specially prepared) solids and liquids will reflect ultrasound very well. The only problem are flat, "specular" surfaces, where the reflected sound is directed away from the source for shallow grazing angles. So sonar works best with "rough" surfaces or when it moves around in clever way that avoids being confused by the invisiblity of such "mirrors" from certain viewing angles.
  16. Related topic / use of sonar by The+Master+Control+P · · Score: 5, Informative

    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.

  17. Re:sonar in air... by adrianmonk · · Score: 3, Informative
    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.

  18. Silly idea after looking at the links. by BlackHat · · Score: 3, Interesting

    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)

  19. Re:What the fuck by Itchy+Rich · · Score: 2, Interesting

    Back on topic however, If naval sonar is so advanced, why is atmospheric sonar so lacking ? isn't it essentually a timing thing (sound travels faster in denser mediums like water than air). put a different emitter on and then adjust the timings.

    Air and water have very different sonic properties. Air is highly compressible, water is less so. Sounds travel short distances in air compared to water... etc.

    Sonar was developed because you can't see underwater. The military has invested huge sums refining it. Above ground we can see, so nobody's bothered researching air-based sonar to the same degree.

  20. Last pic by commodoresloat · · Score: 2, Interesting
    Dude you didn't get rid of him... he's still under that frisbee!

    Seriously this reminds me of an apartment I almost rented years ago... it was an attic of a building; there was a guy living there who was moving out in a few weeks and I was about to hand over the money when I noticed a butterfly net near his futon .... Being a smartass I was like, "Hey, are you a lepidopterist?" He said no, no, that's for the bats. Huh? "Oh it's no big deal - they show up every once in a while. You just turn on the radio to confuse their sonar and catch them with this net." OK, then what do I do? The guy picks up a baseball bat... "You hit it a few times with this bat until it stops moving and then you can flush it down the toilet." I almost lost my lunch right there. I wound up renting a room on the first floor -- so I lived in the house but I never ventured up to the attic after that story. I think bats are really cool but I could not imagine having to catch them and kill them in my bedroom on a regular enough basis to keep a net next to my bed.

  21. Tinfoil Hats by Dareth · · Score: 2, Funny

    ... 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.

    --

    I only look human.
    My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
  22. Good or bad. by Anonymous Coward · · Score: 2, Funny

    Not sure If I'm for or against this.
    On the one hand, bats are scary.
    And yet everyone likes a little head.

  23. Re:Just don't have the robot bat fly into my house by blincoln · · Score: 2, Interesting

    we had always wondered why our cats were going into the room and jumping about.

    Hah. I imagine a flying rodent would be a cat's idea of great fun. Smells like a mouse, flits about like a small bird, add some catnip and it might just be too much to handle altogether.

    --
    "...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman