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Robot Bat With Echolocation

samzenpus posted more than 8 years ago | from the just-the-head dept.

Robotics 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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GNAA Research Division exposes Zionist plot (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#13395151)

GNAA Research Division exposes long standing Zionist plot
Impi - Research Division, South Africa.

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About The Jewish Justice League

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About Areems


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` _______________________________________________' 160-0023 Japan Tokyo-to Shinjuku-ku Nishi-Shinjuku 3-20-2

Copyright (c) 2003-2005 Gay Nigger Association of America [www.gnaa.us]

So, what does your robot do? (5, Funny)

cryptoz (878581) | more than 8 years ago | (#13395155)

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

Re:So, what does your robot do? (1)

Eightyford (893696) | more than 8 years ago | (#13395200)

So you've met my robot then? Sorry but it's really hard to program that sort of thing!

I remember this one... (4, Funny)

TripMaster Monkey (862126) | more than 8 years ago | (#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...

Sounds fascinating! (0, Funny)

Anonymous Coward | more than 8 years ago | (#13395160)

What? It's not MIT? ... so who cares, then?

What the fuck (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#13395172)

Hey, why do you think evolution gave us eyes and 3-D visual brain power? It's much more effective to use vision and realtime 3D processing when in relative low density than sound based ranging. For instance, how would you know something is wet, soft or alive with sound alone?
Oh and can a bat see when I'm drunk?

Re:What the fuck (5, Interesting)

nzkbuk (773506) | more than 8 years ago | (#13395331)

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 ?

Re:What the fuck (2, Insightful)

utnow (808790) | more than 8 years ago | (#13395455)

I think the general conscensus is that a combination of several methods is the best way to observe and interpret the world. Obviously visual isn't the most accurate otherwise eye-witness testimony would mean more and it wouldn't be so easy for hollywood to convince us that keanu revees can fly. Sound isn't nessicarily the best way because it's quite easy to be fooled by such things as a tennis racket being swung through the air (mwhaha). Touch isn't always 100% accurate either due to the way it's wired to the brain (try having a friend cross their index and middle finger and close their eyes. then use a pencil to touch right in the middle of the tips of their crossed fingers. very strange sensation).

The reason we have five senses (and potentially others) is that each of them reduces the uncertainty of the observation.

PS: If you observe certain muscles in the face, they tend to be far more relaxed when intoxicated, resulting in that stupid 'drunk gaze'.

Re:What the fuck (2, Interesting)

Itchy Rich (818896) | more than 8 years ago | (#13396105)

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.

Re:What the fuck (1)

Ihlosi (895663) | more than 8 years ago | (#13396132)

A more likely reason we have 2 eyes is we were origionally predators.

The reason why we have 2 eyes, aligned in a way that lets us judge range, is that our ancestors were hopping from tree to tree. Misjudging distances while doing so can have consequences ranging from "painful" to "removal from the gene pool".

We notice movement and distance well.

Compared to a real predator, we're pretty much blind in these regards.

It helps us hunt.

Not really. Hunters do not need color perception, instead they need high resolution (especially temporal) and good performance through a wide spectrum of light intensities.

We, on the other hand, have sacrificed low-light performance for color perception so we can tell the red fruit from the green fruit and the leaves.

If naval sonar is so advanced, why is atmospheric sonar so lacking ?

Sound (especially ultrasound) attenuation in air is a real pain here, as is the low, low speed of sound in air.

Echolocation (2, Funny)

Gertlex (722812) | more than 8 years ago | (#13395183)

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.

Echo, echo... (3, Funny)

Joey Patterson (547891) | more than 8 years ago | (#13395186)

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

Make it right! (2, Informative)

PaulBu (473180) | more than 8 years ago | (#13395217)

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

Paul B.

Re:Make it right! (0)

Anonymous Coward | more than 8 years ago | (#13395268)

You, sir, read my mind and made my day.

*Cranks C.N.*

Does it go... (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#13395206)



Quick! Get in the Robo Batmobile! Roborobin! (0)

Anonymous Coward | more than 8 years ago | (#13395213)

Gonna cruise for some robo babes.

wrong direction? (5, Insightful)

Pr0xY (526811) | more than 8 years ago | (#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

Re:wrong direction? (1)

superpulpsicle (533373) | more than 8 years ago | (#13395267)

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? (-1)

Anonymous Coward | more than 8 years ago | (#13395508)

And light.

Re:wrong direction? (1)

amodm (876842) | more than 8 years ago | (#13395676)

Even with sight you require two eyes to form a meaningful 3-d image. With one eye, the image will not be stereoscopic.

Re:wrong direction? (2, Interesting)

theapodan (737488) | more than 8 years ago | (#13395808)

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 be a member. And helping furry creatures is good for the soul.

Re:wrong direction? (1)

Ihlosi (895663) | more than 8 years ago | (#13396144)

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.

wrong direction?-Getting Head. (0)

Anonymous Coward | more than 8 years ago | (#13395302)

You remember those "human heads" they use in some recording studios? Same idea.

The "are you a script" word for today is discover.

Re:wrong direction? (3, Informative)

jcr (53032) | more than 8 years ago | (#13395308)

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


Re:wrong direction? (1)

b0r1s (170449) | more than 8 years ago | (#13395720)

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...

Re:wrong direction? (1)

strider44 (650833) | more than 8 years ago | (#13395921)

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".)

Re:wrong direction? (2, Interesting)

TapeCutter (624760) | more than 8 years ago | (#13395929)

"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.

Re:wrong direction? (2, Interesting)

rolfmueller (910054) | more than 8 years ago | (#13395466)

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.

Re:wrong direction? (3, Informative)

mbrx (525713) | more than 8 years ago | (#13395984)

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/ [sourceforge.net] which is an opensource implementation of drivers for various commercial robots as well as some controll functionalities, simulators etc.

Re:wrong direction? (1)

commodoresloat (172735) | more than 8 years ago | (#13396299)

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.

Re:wrong direction? (0)

Anonymous Coward | more than 8 years ago | (#13396489)

It depends on your point of view. For traditional AI, you're absolutely correct. But there is another approach, that says the clever part is the sensors. Provide the right kind of data, and processing it is relatively easy (as in possible). Let the environment do as much of the processing for you as possible.

In this case, the key here is bandwidth. Your standard quartz 40kHz ultrasonic system has virtually zero bandwidth. These guys are working 20-200kHz, so they get much more information were echo. One project is to try to identify plants by their echo image. Clever stuff, and yes, it needs the right sensor system to be possible. They are doing some interesting research into ear shape - it's surprising how much 'processing' is done by physical shape. It's a nice parallel analogue system, which would take a horrible number of cycles to do on a uC.

What sort of 3D landscape map do you want? One that looks nice, like in your favourite computer game, or one that a bat might use to catch dinner and get home again. They're unlikely to look all that similar.

Just don't have the robot bat fly into my house .. (4, Interesting)

xmas2003 (739875) | more than 8 years ago | (#13395250)

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.

Re:Just don't have the robot bat fly into my house (-1)

Anonymous Coward | more than 8 years ago | (#13395451)

You make me sick. Killing innocent squirrels.

Re:Just don't have the robot bat fly into my house (1)

blue trane (110704) | more than 8 years ago | (#13395620)

squirrels can be mischievous...one ran right in my door as i was outside watching him, i had to chase him out. but i wouldn't kill one. unless he was really being annoying and had been duly warned.

Re:Just don't have the robot bat fly into my house (-1, Offtopic)

squidfood (149212) | more than 8 years ago | (#13395578)

I've had six bats show up in my house over the years...

And we were somewhere around Barstow on the edge of the desert.

Re:Just don't have the robot bat fly into my house (1)

krautcanman (609042) | more than 8 years ago | (#13395723)

Funny thing about bats in the kitchen. At work I found a small tupperware of bat heads in the "biological samples only" refrigerator. Must belong to some other lab that use our facilities. Either way, I'd have to say that's the most random thing I've come across yet in my time there.

PS: Mod -1 off topic. I just thought I'd share something random from my otherwise uneventful job.

Rabies (0)

Anonymous Coward | more than 8 years ago | (#13395849)

Just be glad that you didn't get rabies from either one of them. I've heard of one case where a woman was bit by a bat, and didn't even realize it because the puncture wound was so small/superficial. She died several days later.

FYI: If you see a bat during the *DAY*, it most likely has rabies.

Re:Just don't have the robot bat fly into my house (1)

SMS_Design (879582) | more than 8 years ago | (#13395876)

Wow, you are an incredible coward. They are just little bats, and you're a goddamn human being. What do you think they're going to do, clamp onto your face and eat your eyeballs? You freak out each time you see these little creatures that have just wandered into your home.. grow a pair and realize that you are much higher on the food chain.

Re:Just don't have the robot bat fly into my house (1)

SenFo (761716) | more than 8 years ago | (#13396209)

Wow! I would have freaked out if I saw a bat in my house.

Have you ever looked into something like an Ultrasonic Pest Repeller [ebugs.us]? I'm not 100% certain; but, I believe they would work with bats, too. I know for sure that the one my parents have came with an explicit warning to not use the device around pet mice and hamsters.

Last pic (2, Interesting)

commodoresloat (172735) | more than 8 years ago | (#13396323)

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.

I wonder.. (4, Insightful)

jcr (53032) | more than 8 years ago | (#13395289)

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.. (2, Informative)

Eightyford (893696) | more than 8 years ago | (#13395327)

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?

Re:I wonder.. (0)

zippthorne (748122) | more than 8 years ago | (#13395408)

where do you think the word came from?

Re:I wonder.. (1)

strider44 (650833) | more than 8 years ago | (#13395934)

I thought it was this:

> ping www.google.com
PING www.l.google.com ( 56(84) bytes of data.
64 bytes from icmp_seq=1 ttl=241 time=430 ms
64 bytes from icmp_seq=2 ttl=241 time=256 ms

Re:I wonder.. (5, Interesting)

FleaPlus (6935) | more than 8 years ago | (#13395511)

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].

Re:I wonder.. (0)

teaserX (252970) | more than 8 years ago | (#13396335)

... 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.

Re:I wonder.. (1)

rolfmueller (910054) | more than 8 years ago | (#13395531)

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.. (0, Offtopic)

Walt Dismal (534799) | more than 8 years ago | (#13395582)

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.

Re:I wonder.. (1)

baadger (764884) | more than 8 years ago | (#13395902)

Because DareDevil fans would have been pissed that someone with a suit so shit was upstaging him.

Re:I wonder.. (1)

biovoid (785377) | more than 8 years ago | (#13395687)

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.

Re:I wonder.. (1)

CmdrGravy (645153) | more than 8 years ago | (#13396064)

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.

Robot bats?? (4, Funny)

Vombatus (777631) | more than 8 years ago | (#13395307)

Its just not cricket.

Re:Robot bats?? (-1)

Anonymous Coward | more than 8 years ago | (#13396181)

Slashdot is a US site - I thought it was going to be baseball.

i do agree with one thing (5, Interesting)

blackcoot (124938) | more than 8 years ago | (#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).

Re:i do agree with one thing (2, Interesting)

rolfmueller (910054) | more than 8 years ago | (#13395607)

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.

Re:i do agree with one thing - there is more... (1)

munchymuncher (910016) | more than 8 years ago | (#13395960)

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 noise.) So it is very well suited to detecting changes in matter that other waves can pass right through or simply bounce off the mere surface of. There are also different ways to map objects and their locations. The simple approach would be to send out a sound, listen for it to return, then try to decide how far away was the object from which it reflected. An alternative way of mapping would be perhaps a statistical process. First you send out a sound or just listen to ambient noise and determine how many ways it can change. Then you can fly around while you record what you hear. You also want to record each time you run into an object and all of the acoustic features each object you run into possesses. Eventually, you will have enough data to build a statistical probability or regression or whatever model and a derived algorithm for listening to the environment. By using a listening algorithm tailored for the environment, like xmas2003's Frisbee ridden house, the robot bat can simply fly around and guess when it will hit something. The robot bat can even determine if it is about to hit a Frisbee, a window screen, a tennis racket or whatever weapon the flying mammal hater has deployed. This is probably a lot closer to what a live bat actually does. Rather than draw a map of where the moth is, the bat simply remembers what a moth three feet away sounds like and veers in the direction that sounds better. Of course, the live bat's OS is not Linux but Hunger1.0. Not a very stable platform, but the computational power is fantastic! I don't really know a lot about echo location or sonar, but I play like I do on /. I have also seen statistical mapping used in many similar applications like ground penetrating radar. Statistics is applied in geophysical/seismic mapping. Mechanical failure analysis can be done by listening to vibrations which are just below the audible frequencies. Then there is the Weather Channel. So, if statistical mapping of sonar and echo data is not in use by robots for navigation and targeting today, then it will be soon.

Endless amounts of fun! (1, Funny)

RootsLINUX (854452) | more than 8 years ago | (#13395361)

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!

Just don't arm it. (0, Offtopic)

Anonymous Coward | more than 8 years ago | (#13395410)

Fish, Please reenter the water, you have 20 seconds to comply"

"Okay, I'm getting in!"

"Unable to read from Infrared device, abort, retry, ignore?"

"What? Uhh, Abort!! Abort!!"

"Unable to close application, terminate now, or wait another five seconds?"

"Terminate! Stop! Halt! Please, goddamit!"

Holy Cow Batman!! We're on the batnet!! (2, Funny)

Anonymous Coward | more than 8 years ago | (#13395362)

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.

Ultrasound band saturation? (1)

Max Romantschuk (132276) | more than 8 years ago | (#13395367)

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...

Re:Ultrasound band saturation? (2, Informative)

rolfmueller (910054) | more than 8 years ago | (#13395563)

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.

Re:Ultrasound band saturation? (1)

frozen_kangaroo (755476) | more than 8 years ago | (#13396228)

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 dark at the time and they do have eyes they could use)

Also, even though the emissions from your bat head are directional, the reflected signals aren't going to be. A bat could pick up the reflected signals from another bat if his/her ears were pointed in the right direction. Temporal domain "filtering" is possible: speed of sound in air 330m/s; therefore anything heard >~100ms after emission can be disregarded, but when they go for their prey I noticed that they don't leave a lot of a gap between clicks - making very rapid repetitions of noises until they catch that insect.

Another consideration - the consequences of getting an eroneous picture of the world around you and subsequent poor navigation could result in injury - a big deal for a creature that has to be able to fly to catch food. IMVHO it is unlikely that they haven't evolved anti-jamming technology.

Humans can recognise an individual voice in a crowded room - it is possible to "tune in" to a conversation at a table behind you in a crowded restaurant above all of the noise in the same frequency band. From my experience of DSP, I would hate to imagine the complexity of what is going on in the brain in this situation, but clearly it can be done - the neuro/physiological processing such as that found in hearing and sight leaves me in absolute awe.

Bat emissions look pretty complex to me, and I'm willing to bet that they do identify their own squeak amongst all of the other noise. Modern radar uses correlation and signature techniques that mean that they only identify their own emissions. Why not bats ? Is this part of your project ? [ good luck with the work by the way it sounds like great fun. ]

Re:Ultrasound band saturation? (1)

rolfmueller (910054) | more than 8 years ago | (#13396434)

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 window for reception, I expect that jamming is not much of a problem and bats probably do not require much sophistication in dealing with it.

For these reasons, I am not inclined to throw precious resources at this. Maybe I'll hand out a master thesis project one day to come up with an estimate of how close bats have to be packed for jamming to become a problem. But I expect you would end up with a "sardines in a tin" packing.

[thank you for your input & good wishes]

Why in the world.... (1)

keilinw (663210) | more than 8 years ago | (#13395460)

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 technology is only going to be good at things that reflect sound. Is it going to be good for people avoidance? Tree / shurb avoidance? Maybe.... but then again any addition information is better than none.. that is if it were suplimented with appropriate visual /tactile sensors, etc.

--Matt Wong

Re:Why in the world.... (2, Interesting)

rolfmueller (910054) | more than 8 years ago | (#13395636)

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.

Echolocation as a group sense. (0)

Anonymous Coward | more than 8 years ago | (#13395554)

Echolocation as a group sense in animals and robots.


Please, please, please... (1)

bensafrickingenius (828123) | more than 8 years ago | (#13395562)

...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?

Robot bat with ejaculation? (-1)

Anonymous Coward | more than 8 years ago | (#13395681)

Why would we want that?

Christ, Forgive Us !! (1)

jpiggot (800494) | more than 8 years ago | (#13395736)

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.

Related topic / use of sonar (5, Informative)

The Master Control P (655590) | more than 8 years ago | (#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.

sonar in air... (1)

kgarcia (93122) | more than 8 years ago | (#13395769)

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... (3, Informative)

adrianmonk (890071) | more than 8 years ago | (#13395847)

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.

Re:sonar in air... (1)

rolfmueller (910054) | more than 8 years ago | (#13395862)

Radar uses electromagnetic waves, in-air sonar uses ultrasound. Ultrasound frequencies are by definition above the audible spectrum, so you don't hear them.

Silly idea after looking at the links. (3, Interesting)

BlackHat (67036) | more than 8 years ago | (#13395850)

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)

Re:Silly idea after looking at the links. (1)

rolfmueller (910054) | more than 8 years ago | (#13395925)

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 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.

Re:Silly idea after looking at the links. (1)

BlackHat (67036) | more than 8 years ago | (#13396002)

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.

generalization not true. (0)

Anonymous Coward | more than 8 years ago | (#13395911)

Whenever a robot team wants to build an autonomous robot they look at sonar first...

Sonar has a place, but is by no means the first thing that everyone looks at when designing an autonomous robot. I imagine most would like to use cameras, but the complexitys of image analysis put that out of reach(for most), so they look at more simple sensors such as sonar/laser range finders/antennae.

Though all of this depends on the builders skill and the projects needs.

Hmmm.. (1)

Francis85 (875901) | more than 8 years ago | (#13395939)

Lets get this straighten out.. they made cyborg bats with friggin' radar beams attached to their heads!!

The list of articial nature (1, Funny)

jurt1235 (834677) | more than 8 years ago | (#13395985)

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 cockroaches
For on the benches in the parks, which without real nature will be less attractive anyway, all dirt which is now cleaned up by nature, will stay around, we will have cute looking japanese femal robots able to wave at you when you drive by, making it look very lively.

That's Nothing... (1)

Legendof_Pedro (900265) | more than 8 years ago | (#13396265)

Get back to me when it can fly.

A head that can ecolocate is nothing - we've been using sonar and radar for years.
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