Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Technology

Autonomous Underwater Vehicle Competition 66

krugg234 writes "Today [ed. note: well, a few days ago] marks the start of the Fifth Annual International Autonomous Underwater Vehicle Competition. This year's competition involves completely autonomous robots locating and reading bar codes at various depths underwater at a naval base in San Diego. There are some good links on the site to individual competitors' websites to see how different schools tackled the same problem."
This discussion has been archived. No new comments can be posted.

Autonomous Underwater Vehicle Competition

Comments Filter:
  • The Navy must be planning on setting up underwater grocery stores for dolphins. Well, they'll have the market cornered...
  • by Styx ( 15057 ) on Saturday August 03, 2002 @02:44PM (#4005390) Homepage

    The US Naval Academy is participating in this contest. Their vehicle is powered by ... a pc104 running Windows 98 [usna.edu]...

    Some people might say that the navy hasn't learned anything from the past [info-sec.com]...

    :-)
    • The US Naval Academy is participating in this contest. Their vehicle is powered by a pc104 running Windows 98

      Somebody must have told them that Windows 98 goes down faster than anything else on the market.
    • The article you cite was, according to it's own publisher who later backed away from it, early speculation. Reality did not match the speculation. According to people actually on the ship and who actually worked on the software:

      http://www.sciam.com/1998/1198issue/1198techbus2.h tml

      Others insist that NT was not the culprit. According to Lieutenant
      Commander Roderick Fraser, who was the chief engineer on board the
      ship at the time of the incident, the fault was with certain
      applications that were developed by CAE Electronics in Leesburg, Va.
      As Harvey McKelvey, former director of navy programs for CAE, admits,
      "If you want to put a stick in anybody's eye, it should be in ours."
      But McKelvey adds that the crash would not have happened if the navy
      had been using a production version of the CAE software, which he
      asserts has safeguards to prevent the type of failure that occurred.

      The programs that crashed were LAN terminals, not the LAN itself. A server app corrupted it's own database and client apps naively tried to use the bad data. At least in the debug version of the apps. These app controlled this ships equipment. The OS wasn't involved and it would have mattered what OS was being used.
  • Now I can have a fly ride to pick up some fish-tail mermaid honeys, we can cruise on over to my fish crib and just bounce.
  • That's how you recognise a hostile nuclear sub: read the barcode. Presumably IFF doesn't work under water so our hunter-killers have to rely on correct labeling. And now we know why so many spies were needed in the Cold War: they were trying to get the codes for the entire Nato and Soviet fleets.

    Scan the bar code, launch the torpedo: the message comes back over the VLF "You have destroyed a Russian cruiser. That is a total of 550 points on your reward card. Do you want to choose a gift now?"

    Extreme cynicism aside, however, this kind of competition is surely a Good Thing, and I wiash it had been around when I was a student.

  • To spice things up, why not allow the teams to equip their subs with short-range torpedoes? This would be fun to bet on. Also, it would serve as a more practical simulation of where modern warfare is headed. This would be even more badass if they used instead. [mit.edu]
  • most of the teams that are actually recording bar codes are just using a simple webcam in waterproof enclosure. the on-board computer then performs some processor intenstive code to recognize bar codes in all sorts of conditions (orientation, etc).

    what i'm curious about is why no-one went with a bar code reading system similar to that in use in a grocery store? certainly the hardware modifications are possible to make a cheapo and less processor intensive solution like that work underwater.

    thoughts??
    • One word: Noise.

      The vast majority of the processing carried out by a typical laser-based Bar-Code reader is to eliminate the amount of noise in the input signal - which can be quite significant. In an underwater environment, the amount of noise in the input signal is going to be considerably higher, perhaps to the point where the actual data is drowned out.
      • Maybe a little more info.

        Lasers don't work that well underwater because water distorts light and various wavelengths. The deeper you go for instance, the less natural light would be recieved (less light = more noise).

        Plus, most supermarket scanners use a red laser to scan barcodes, and red is one of first wavelengths to fade as you go deeper. Kodak even sells special underwater film that is extra sensitive to red wavelengths so you can take more natural looking pictures further down.

        My guess is they are using webcams because the refractive qualities of water makes using lasers more difficult than getting a webcam and some image processing software.
        • I'm confused. I won't pretend to be an expert on any of this, but your comment doesn't seem right to me at all. Correct me where I'm wrong, etc, but here's my take. They're probably using the camera, because they need to visually find the barcode to begin with. Barcode scanners are excellent for reading a code that's positioned in front of the reader, but once you've gone through the trouble of locating the code with your camera, you might as well just finish the job and read the code.

          Now about the light issues. This doesn't seem right at all. Light doesn't bend more underwater than in air -- it bends at the transition between different optical densities. Since there would be no transitions underwater, the light wouldn't bend.

          The deeper you go for instance, the less natural light would be recieved (less light = more noise).
          Isn't the whole point of using a laser, to eliminate the need for (or interference from) other sources of light? It is very easy to detect a specific frequency of light as it contrasts to black, so I highly doubt barcode scanners care at all about ambient light. I haven't tried it, but it would surprise me a lot to find that barcode scanners don't work in the dark, for instance.
          red is one of first wavelengths to fade as you go deeper
          Again... the light coming from the sky fades at that depth, but I submit that such light would make no difference.

          For all I know you invented the bloody barcode scanner, so maybe I'm talking out of my butt. But then, maybe you are. ;) These are my reasoned opinions, and if you have more details to back yourself up I'm very interested in hearing them. :)

          • Well, I may be a little rusty, I'm relying on some things I read about years ago.

            I think the issues I read about related to why the Navy didn't use lasers/light for some things (I forget what they were...mapping terrain, communications, etc), rather than acoustics/sonar. Apparently sounds work better than light underwater for those types of things. Anyway...

            While light will bend at the difference in optical densities (like a prism), the problem with using a laser underwater is dispersion (signal:noise). Water holds a lot of particulate matter. This is supposed to take place in a large outdoor tank, so it probably has a lot of stuff suspended in the water. It's may be too small to see, but it would probably make using lasers difficult. The closer they got to the barcode, the easier it would be to use a laser, since the distance would be shorter (more signal, less noise). They could probably play with the software to account for some variability.

            Also, since water pressure increases as you go deeper, it may affect the density (it's Saturday, I don't want to think too hard). In a lab, "pure" water is supposed to have a specific gravity of 1 (weight/volume). Again, we are not talking about "pure" water, because it's a large tank outside. Water temperature will affect the density, as well as the content (particulate matter, etc). If you read enough Tom Clancy books, you know that the thermocline layer can affect acoustics/sonar, but that probably wouldn't affect this, since it's in a tank, not the ocean.

            Another engineering point would be inertia. These robots aren't going to stop on a dime. They can stop the props, but they will keep moving, so they would probably have to read a moving target. And even though it is a pool, there may be some currents from divers, pumps, etc.

            I thought they would use some sort of acoustics to find the objects, and then use the webcam/whatever to read the code. I read the rules, and the object in the center will have an acoustic pinger (probably to orient the robot to the tank). From this, the robot could (theoretically) calculate where the other objects are in the tank and go to each one and take a picture (so to speak).

            Anyway, I'm not saying these things can't be done. Each team looked at the challenges and decided how they would go about solving them. They are all engineering issues, which is what competitions like these are all about. I look forward to reading some of the journal articles afterwards to see what the teams learned from the experience. I imagine that will answer these questions better (i.e. experience)
            • I work at a library, and we use laser barcode scanners to identify books, etc to check them in/out/elsewhere. I don't know how they work, and I never actually tried using one underwater, so I don't have really good 'experience', but here's my two cents.

              First of all, the supermarket scanners were mentioned before, and I think that might actually be a better design than the library's scanners for this sort of thing. If you ever watch these things in action, the person practically throws them over a glass square about 8x6in or so. It's hardly precision scanning.

              At the library, we have standing scanners on arms that direct the red line down onto a book's barcode. If you get a barcode anywhere beneath it, it will read it. I've scanned things in motion, at an angle, etc. I haven't tried in the dark, but I'm pretty sure it would work.

              Lastly, and this is purely hypothetical, if a laser scanner worked well enough, a brute force attack would be possible--get a couple scanners on all sides, and just zoom around the tank and record what scans!

          • Nah, the barcode scanner was invented by an engineer turned business owner from California. I can't recall his first name, but the last is Baglio.
            He doesn't read slashdot, at least as far as his son Vic has told me.

            There's no reason for the scanner to stop working without any light. A lot of red ambient lighting might interfere, though... But all the same, I would expect it to be less effective underwater. You don't get refraction since there are no transitions but you do get more scatter of the beam from the density of the water as opposed to air. Well, that's not entirely true... You'll have refractions anyway since the beam has to pass from a sealed emitter, through glass/plastic and finally into water, but these should be predictable and compensated for.
            An underwater scanner would need to be much more sensitive and have a far more refined laser. This is prohibitively expensive as compared to a cheap webcam with some software.

            And then there's the matter of getting close enough to scan properly...
    • by Anonymous Coward
      Actually, I'm one of the competitors (I'm typing this from the competition now). The reason that most of the teams use webcams basically comes down to what's available to us students. Most of our equipment is old, second-hand stuff or borrowed from several robotics companies. Actually, the way grocery stores read bar codes was taken into account when we decided how we were going to read them (I wish I could tell you more about how ours works, but I'm sure I'm not the only competitor who reads slashdot!). Also, the camera requires less modification to allow us to home in on the barcodes so that we can read their depths, which is the other objective.
    • Why process on board at all? The rules as I read them say after the run you get to hook your vehicle to a dockside computer to download the data. Processing could be done there or you could simply display the pictures and read them with your eyes. Humans are good at removing all kinds of noise from images. Then write the results on a slip of paper and pass it to the judge. Also allowed by the rules. You get 5 minutes, it should be easy. Might not get you all the discretionary points though.
  • Finally, something to use those old school NASA programs on!

    forget it.
  • if these things have cameras transmitting underwater pictures, the windows teams might run into problems: windows team captain: okay, guys. let's submerge it operator: sir, i got a bluescreen. captain: ok. bring it up, recompile, reboot and try it again. goto 1;
  • Wow (Score:1, Flamebait)

    Discussion of this article is swimming about as well as a retarded dolphin..

    Don't we HAVE technology like this? what about that gizmo that took picturs of the Titanic wreck?
    • I don't think the gizmo that found the Titanic was autonomous. It had an umbilical that was connected to someone in a sub or ship, where it was controlled by a person.
    • From the Gulf of Maine Aquarium website:
      "Jason Jr. is a remote-controlled underwater robot that explored the interior of the sunken Titanic on Ballard's second expedition. It was operated by a remote control "joy stick" to probe inside the Titanic to take still and video images. It went into the grand ballroom, captain's stateroom, and down several flights of stairs. It was tethered to Alvin via a long cable."
      Therefore, it was not autonomous.
  • Why dont they just hook up a moded cue-cat to a remote controled toy submarine?
  • While this is definitely an interesting competetion (autonomous anything is very cool - especially when they have to go against both nature and a task), I wonder how this will work with respect to practical application. I can see having to autonavigate to a destination, but why scan a barcode. Why not just have it retreive a spoon or something?
  • by Tablizer ( 95088 ) on Saturday August 03, 2002 @05:33PM (#4005943) Journal

    I assume Ted Kennedy will be in the race.
  • My friend is a coder for the avbotz.com team. While sitting here screwing around doing nothing worthy, he would be IM'ing me constantly about his B-tree optical algorithm.
  • I'm entering my Sharks with frickin' laser beams!
  • ... I hope that the autonomous unwater bots will capture some fish and then barcode them.

  • 1998 - 2nd
    1999 - Honorable Mention
    2000 - 8th
    2001 - They sent a fucking CS student to do what an EE and an ME student were supposed to do, the dumb fuck didn't even pressurize the fucking sub, so when he put it in the water it went *blubblubblub* to the bottom of water.
    2002 - We're not even listed.

    I'm glad that the navy is using Win98 so that we can make fun of them, but goddammit, I'm still crying at our school's inability to comprehend that the students might honestly be more interested in working on something cool than something profitable.

Don't tell me how hard you work. Tell me how much you get done. -- James J. Ling

Working...