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Math Science

The Math of a Fly's Eye May Prove Useful 90

Posted by kdawson
from the saw-that-one-coming dept.
cunniff writes "Wired Magazine points us to recent research that demonstrates an algorithm derived from the actual biological implementation of fly vision (PLoS paper here). Quoting the paper: 'Here we present a model with multiple levels of non-linear dynamic adaptive components based directly on the known or suspected responses of neurons within the visual motion pathway of the fly brain. By testing the model under realistic high-dynamic range conditions we show that the addition of these elements makes the motion detection model robust across a large variety of images, velocities and accelerations.' The researchers claim that 'The implementation of this new algorithm could provide a very useful and robust velocity estimator for artificial navigation systems.' Additionally, the paper describes the algorithm as extremely simple, capable of being implemented on very small and power-efficient processors. Best of all, the entire paper is public and hosted via a service that allows authenticated users to give feedback."
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The Math of a Fly's Eye May Prove Useful

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  • by pete-classic (75983) <hutnick@gmail.com> on Friday November 13, 2009 @11:16AM (#30087728) Homepage Journal

    After presenting his paper, researcher David O'Carroll strode off the stage and into a sliding glass door.

    -Peter

  • by hatemonger (1671340) on Friday November 13, 2009 @11:19AM (#30087788)

    The researchers drew their algorithm from neural circuits attuned to side-to-side yaw, but O’Carroll said the same types of equations are probably used in computing other optical flows, such as those produced by moving forward and backwards through three-dimensional space.

    I vaguely remember seeing a study that examined how bees travel without hitting anything but using very few neurons. Something about the relative size change of objects between eyes. They tested this by putting bees in a clear tunne with patterns on belts on the right and left walls. By changing the speed of the belts, the bees would ram into the walls, but as long as the belts were moving at the same speed, the bees were fine. Is this ringing a bell for anyone else?

    • by Bazzargh (39195) on Friday November 13, 2009 @11:39AM (#30088066)

      You mean this: http://www.ncbi.nlm.nih.gov/pubmed/2069903 [nih.gov] "Range perception through apparent image speed in freely flying honeybees."

      • Thanks. You're my hero. So we've solved side-to-side yaw and moving forwards and backwards in 3-d space... now if only we could find something in nature we could copy (without fully understanding) that hunted for Sarah Connor.
    • They should have all this stuff implemented also relatively easily, I guess, and they appear quite "ultimate" when it comes to perception in bugs.

      I seem to remember they follow some impressive flight pattern when pursuing their prey - first remaining stationary in relation to background image perceived by prey, and then, in final moments, stationary in relation to vision of prey.

    • by StikyPad (445176)

      Any explanation for why moths fly into anything and everything? It's especially irritating when living in a warm climate with moths the size of small cars.

      • by Gorobei (127755)

        Um, because they fly at night when optical flow techniques are useless? So they use "constant angle w.r.t. to the moon" navigation. Which worked great until humans added 10 billion artificial moons to the environment.

      • by fractoid (1076465)

        Any explanation for why moths fly into anything and everything? It's especially irritating when living in a warm climate with moths the size of small cars.

        Pretty simple, actually. They navigate using the moon as a reference point, since it's essentially a directional light. In order to fly straight, they keep the moon at a particular point in their field of vision. Sadly, when the brightest object in their field of view is a light bulb, keeping it in the same position in their field of view results in them spiralling madly around and towards it.

        So moths don't really like bright lights, candle flames etc. Lights just screw with their navigation system.

  • by erroneus (253617) on Friday November 13, 2009 @11:21AM (#30087824) Homepage

    Why does this sound like every PC user and quite a few programmers I have had to deal with?

    I find it unimaginable that people would attempt to implement a technology that is not fully understood. Doing so will eventually yield unexpected results or at the very least, results that cannot be explained.

    I am not saying that everything we presently or regularly do is something that everyone presently understands as I am sure there are ample examples of this happening everywhere. Usually, however, "someone" somewhere actually knows and understands because they created it. In this case, it seems, things are being created and implemented without a full working understanding of how it all works. At the very least, such inventions should be unworthy of patenting.

    • by Anonymous Coward on Friday November 13, 2009 @11:24AM (#30087864)

      You'd be surprised. About medicine.

      Starting with simple Aspirin, the line of medicaments that have known positive results but nobody knows why, is loooooooong.

    • Re: (Score:3, Insightful)

      by 4D6963 (933028)

      Why isn't it modded off-topic? So we don't know everything for sure about how a fly's brain works, but it doesn't matter, because we're looking at them for inspiration for the algorithms actually implemented, which we actually understand. No one's stupid enough to not understand their own algorithms, at least not at that level.

      • Re: (Score:3, Interesting)

        by Rockoon (1252108)
        I believe the poster was talking about understanding the algorithm itself, not the fly brain.

        The key idea here is that emergent algorithms (which is what these sort of things are) are unpredictable. It is one thing to understand the methodology, another to grok the full picture.

        In any sort of complex input space, you cannot test all possible input permutations and so cannot guarantee that these algorithms wont go ahead and output the worst possible thing from time to time.

        In some cases we can get away
      • Re: (Score:3, Interesting)

        by PitaBred (632671)
        Stupid? They're multiple non-linear equations interacting with each other. The people who came up with the algorithms themselves state that they don't understand the full effects of the algorithms. They know that they work, they know if they remove parts of the algorithm they stop working nearly as well, but they can't predict the output from the input.
    • by hatemonger (1671340) on Friday November 13, 2009 @11:33AM (#30087970)

      I find it unimaginable that people would attempt to implement a technology that is not fully understood. Doing so will eventually yield unexpected results or at the very least, results that cannot be explained.

      Except that occasionally building a working model is a useful step to understanding it. I'm happy that Edward Jenner in 1796 started infecting people with cow pox as a way to prevent small pox even though he didn't fully understand why it worked.

    • Re: (Score:1, Insightful)

      by Anonymous Coward

      Maybe you need to stop dealing with Indian outsourcing firms and their "programmers"?

      When all you program for is Windows and .NET like they do, and most of that is closed-source to most developers, of course you won't have a fucking clue what's going on.

      Almost all of us open source developers know what's going on from the the hardware up. We can see ever layer of the Linux, FreeBSD or OpenSolaris kernels, for instance. Those of us who did chip design in the past also know how the hardware works (and we usua

    • by MBCook (132727) <foobarsoft@foobarsoft.com> on Friday November 13, 2009 @11:35AM (#30087990) Homepage

      Well, it's not flying airplanes full of people. They've copied a system that seems to work well, and they are testing it for ultra-small UAVs. They'll get a better idea of how it works then.

      There are many things people have used throughout history without understanding how they work. Salt preservation is ancient, but we didn't discover the bacteria it kills until the last 200 years.

      Sometimes, "works" is good enough. And works often leads to understands.

      I think this is really cool. We've been trying to do this kind of thing for years. The fly does it with a tiny-micro-fraction of the resources we were using, and does a much MUCH better job. By testing this system, perhaps we'll find out WHY our systems are tricked by certain stimulus and this one isn't.

      It's not like they put a bunch of stuff together and said "this works, as far as we can tell", they took a proven system and copied it.

      • by ejtttje (673126)

        they took a proven system and copied it.

        And not just copied it (it's easy to breed flies :), but translated it into mathematics! This will open it to a much broader audience for analysis and adaptation into working systems. I'm really excited to see how this research pans out... vision processing is a major hurdle for robotics today, and this could have significant impact.

      • by sznupi (719324)

        I would be also interested in determining which stimulus can trick even fly system...

      • Speaking of airplanes, I don't fully understand how the pilot converts sensory input to control surface instructions, and I'm certain that there are many cases where the pilot's reaction will be absolutely the worst thing possible. Still, the risk is worth it when you consider the alternative of not having high-speed continental or global travel.

        The bar of plugging something in instead of a pilot is not at "do we understand what it will do in all circumstances" but the much more attainable, "will it perfor

    • Re: (Score:3, Interesting)

      by Nobo (606465)

      A scientist says, "This works, but I don't know why, How do I complete the theory?"
      An engineer says, "This works, but I don't know why. How do I use it to build something that does what I want?"
      A good engineer says, "This works, but I don't know why. How do I use it to build something that does what I want.. And, in what domain does my model break down and how do I make sure I don't get my system into that domain?"

      Sizable chunks of control theory, frequency analysis, and some other core theoretical compo

      • Re: (Score:3, Interesting)

        by Anomalyst (742352)

        A scientist says, "This works, but I don't know why

        Here is my falsifiable hypothesis, I'll test it experimentally and see if successful results can be reproduced independently.
        Theory comes a LONG ways down the road.

    • by epine (68316)

      I find it unimaginable that people would attempt to implement a technology that is not fully understood.

      This is precisely why this kind of algorithm has remained undiscovered over such a long period of time that people have begun to speculate that the human brain employs a quantum magician behind the curtain. Not so. We're just slow on the uptake. (I find this amazing: against the backdrop of our intellectual failings, we manufacture glory for our miraculous cognition.)

      Compositions of non-linear components tend to defy traditional explanation. We've done a pretty good job of mining the ore where our prefe

    • by middlemen (765373)

      I find it unimaginable that people would attempt to implement a technology that is not fully understood. Doing so will eventually yield unexpected results or at the very least, results that cannot be explained.

      Yes, as we can see very well in the financial industry today. "Algorithms" and complex "trading strategies" implemented without understanding the fundamentals.

  • Okay, so the article is titled "Secret Math", and...

    Though they built the system, the researchers don’t quite understand how it works.

    and...

    Intriguingly, the algorithm doesn’t work nearly as well if any one operation is omitted. The sum is greater than the whole, and O’Carroll and Brinkworth don’t know why.

    Wow, some interesting "science" that's going on here.
    Great result, but, really, way to go guys! You can't understand a non-linear system's behavior; join the club. I still can't understand why z_n+1 = z_n^2 + c looks so pretty either.

    • Great result, but, really, way to go guys! You can't understand a non-linear system's behavior; join the club. I still can't understand why z_n+1 = z_n^2 + c looks so pretty either.

      Maybe your mother had a little z_n in her and it's a latent Oedipus complex?

    • I don't need to know how the chemistry of combustion works to be able to use it to make a fire to cook food, generate light and heat for my shelter, and so on. Fire was not well understood as a chemical process until relatively recently; certainly not until after the discovery of oxygen in the 1770s.

      It frustrates nerds to no end, but "why" is often a pretty useless question to ask in the grand scheme of things:
      "The hard drive seems to have failed."
      "Why?"
      "I could answer that with a level 4 clean room and a

  • Extinction (Score:2, Interesting)

    by citylivin (1250770)

    You know I can forsee a time, a few hundred years down the line, where we are recovering from the environmental catastrophe caused by man. In this time I think the great profiteers of the day will look down shamefully on the profiteers of today, who destroyed so many of natures feats of engineering in order to harvest lumber or food. I think that they will look back at all the diversity that could have been exploited for their designs and curse us. Mankind will probably be roaming the stars in search of bio

    • by vertinox (846076)

      Mankind will probably be roaming the stars in search of biodiversity by then.

      Wouldn't it be easier to simply build a Dyson spheres and computers as large as planets to simulate bio-diversity if needed.

    • by maxume (22995)

      I certainly hope to be recovering from an environmental catastrophe in a few hundred years.

  • They don't even know how it works! Cue ominous music...

    So, how about that for borrowing work? Rely on biological optimizations that have undergone hundreds of millions of generations with billions of test configurations!

    In general, I don't see that this can generally be applied to CS, due to the implicitly parallel nature of biology, but I guess this case must not be too bad.

    At any rate, TFA is fairly interesting - even the wired report is fairly informative.

  • A good read... (Score:3, Insightful)

    by CockMonster (886033) on Friday November 13, 2009 @11:39AM (#30088064)
    But where's the source code???
  • by alta (1263)

    Here we present a model with multiple levels of non-linear dynamic adaptive components based directly on the known or suspected responses of neurons within the visual motion pathway of the fly brain. By testing the model under realistic high-dynamic range conditions we show that the addition of these elements makes the motion detection model robust across a large variety of images, velocities and accelerations

    Did anyone else's head hurt after reading that?

    Shouldn't "these elements makes" drop the last 's'? If so, what a dumbass. ;)

    • Re: (Score:1, Informative)

      by Anonymous Coward

      No. Addition is the subject of the verb makes. Subject-verb agreement says the original post is correct. Get your grammer rules right first if you're going to criticize.

    • by puthan (155000)

      No. Since the makes refers to the model and not to the elements.

      • by puthan (155000)

        Let me rephrase that. The makes refers to the addition of the elements, which ill be treated as a single object.

  • by PPH (736903) on Friday November 13, 2009 @03:57PM (#30091692)
    We've implemented this algorithm in several autonomous flying surveillance vehicles. While it appears to work adequately, we're still trying to determine why the only thing they manage to locate is cow shit.
  • Refreshing Story (Score:5, Insightful)

    by BJ_Covert_Action (1499847) on Friday November 13, 2009 @05:56PM (#30092934) Homepage Journal
    This might be offtopic but seeing a legitimate R&D story on slashdot with a link to the actual (open) technical write up of the research made my day. I haven't read the whole paper yet (I will when I get home) but going through it and reading the first few sections I can see that the researchers included their (simulink?) processing models as well as some good data in the results section. This story finally gave me something worth breaking out my old signal processing and DAC notes from college out over and studying the raw math and theory behind the algorithm.

    I have to say, I really wish we would see more papers like this posted and published openly. It's very inspiring when other folk in similar fields can access a paper's full contents and start playing with similar models themselves...
  • and power-efficienct processors."

    Given the inspiration for the algorithm, why would this be so surprising?

  • I think this must be the first of a new kind of computer science. Reverse engineer something from even an insect brain to create a computer program, is completely new to me. As you can see from the diagram, this is very different to the neural networks some AI researchers (but no biologists) claim mimic the human brain. It does look like an evolved algorithm, in the sense that works very well and efficiently but there no obvious design or understanding of how it works.

    ---

    AI [feeddistiller.com] feed @ Feed Distiller [feeddistiller.com]

    • It does look like an evolved algorithm, in the sense that works very well and efficiently but there no obvious design or understanding of how it works.

      Funny... when faced with an algorithm that works very well and efficiently yet whose design seemed to escape me and gave me no understanding of how it worked, I'd have concluded that it appeared to be designed by someone a whole lot smarter than myself.

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