Slashdot Mirror
Fish-like Sensors for Underwater Robots
Roland Piquepaille writes "Today, both submarine and surface ships use sonar for navigation. But sonar and other vision systems face various limitations. So why not imitating fish? For millions of years, fish have relied on 'a row of specialized sensory organs along the sides of their bodies, called the lateral line' to avoid predators or to find preys. So engineers at the University of Illinois at Urbana-Champaign (UIUC) have decided to build an artificial lateral line for submarines and autonomous underwater vehicles (AUVs). The first tests have been successful, and we can now envision a day where AUVs could detect and track moving underwater targets or avoid collisions with moving or stationary objects."
Truly, this is a question that will plague both scientists and engrish majors for years to come.
Obligatory Soundbite Catchphrase
Indeed. Why not imitating fish? All your gills are belong us.
CHAMPAIGN, Ill. -- To find prey and avoid being preyed upon, fish rely on a row of specialized sensory organs along the sides of their bodies, called the lateral line. Now, a research team led by Chang Liu at the University of Illinois at Urbana-Champaign has built an artificial lateral line that can provide the same functions in underwater vehicles.
"Our development of an artificial lateral line is aimed at enhancing human ability to detect, navigate and survive in the underwater environment," said Liu, a Willett Scholar and a professor of electrical and computer engineering at Illinois. "Our goal is to develop an artificial device that mimics the functions and capabilities of the biological system."
In fish, the lateral line provides guidance for synchronized swimming, predator and obstacle avoidance, and prey detection and tracking. Equipped with an artificial lateral line, a submarine or underwater robot could similarly detect and track moving underwater targets, and avoid collisions with moving or stationary objects.
The artificial lateral line consists of an integrated linear array of micro fabricated flow sensors, with the sizes of individual sensors and spacings between them matching those of their biological counterpart.
"By detecting changes in water pressure and movement, the device can supplement sonar and vision systems in submarines and underwater robots," said Liu, who also is affiliated with the university's Beckman Institute for Advanced Science and Technology, the Institute for Genomic Biology, and the Micro and Nanotechnology Laboratory.
Liu and colleagues at Illinois and at Bowling Green State University described their work in the Dec. 12, 2006, issue of the Proceedings of the National Academy of Sciences.
To fabricate the tiny, three-dimensional structures, individual components are first cast in place on sacrificial layers using photolithography and planar deposition. A small amount of magnetic material is electroplated onto each of the parts, which are then freed from the substrate by an etchant. When a magnetic field is applied, the induced torque causes the pieces to rotate out of the plane on tiny hinges and lock into place.
Each sensor is integrated with metal-oxide-superconductor circuitry for on-chip signal processing, noise reduction and data acquisition. The largest array the researchers have built consists of 16 flow sensors with 1 millimeter spacing. Each sensor is 400 microns wide and 600 microns tall.
In tests, the researchers' artificial lateral line was able to localize a nearby underwater vibrating source, and could detect the hydrodynamic wake (such as the wake formed behind a propeller-driven submarine) for long-distance tracking. With further advances in engineering, man-made underwater vehicles should be able to autonomously image hydrodynamic events from their surroundings, Liu said.
"Although biology remains far superior to human engineering, having a man-made parallel of the biological system allows us to learn much about both basic science and engineering," Liu said. "To actively learn from biology at the molecular, cellular, tissue and organism level is still the bigger picture." ###
The work was funded by the U.S. Air Force Office of Scientific Research and by the Defense Advanced Research Projects Agency.
Don't worry most of /. users wouldn't like to socialize with you either.
And the loosing party will be you, moron.
As far as I can tell from the article (hah!), the flow-sensors aren't new, though they may be uniquely orientable with applied magnetic fields. Really, this just looks (to me) as though it's a low-frequency linear acoustic array, and those have been used for a LONG time for this sort of thing. It seems to me that the individual sensors might be what are actually of interest.
lol, u r a jew.
PETA's gonna be mad when sharks eat these.
Tag suggestion: preys
Wrong, I am a Catholic, you guessed incorrectly.
BTW: go back to primary school and learn how to write.
I'm glad this technology will help keep us safe from terrorists with submarines, now can we give up Low Frequency Active Sonar?
We are all just people.
According to this article the timing couldn't be better if we assume that China is actually a world power with the capability of projecting force. Politically they are quite happy with their relationship to the U.S. Militarily there isn't much of a chance that we'll be playing in the sandbox nicely together.
load "$",8,1
Oh great, another Ronald PorkPie story on slashdot...
Seven puppies were harmed during the making of this post.
Now I can eat subs raw
sometimes, nothing.
The article implies that we could replace sonar with the lateral line:
But sonar and other vision systems face various limitations. So why not imitating fish?
The lateral line is truly an amazing organ. It senses pressure and flow at numerous points on both flanks of fish, and that information helps it swim efficiently and indeed locate prey and avoid predators.
But it's fundamentally a local signal, because it can only detect within a certain range and with limited resolution. A fish can't use the lateral line to make sense of the 3D shape of an object ten meters away, because that information simply isn't transferred through the water that far.
Sonar can indeed do that, and can locate and take velocity measurements on objects *miles* away. So useful, in fact, that dolphins use it as one of their primary sensory systems, apparently getting almost as much detail from sonar as they do from vision.
A lateral line may be a very useful addition to an underwater craft, but it can't replace it as the summary implies. (TFA is smarter, BTW. Go figure.).
I stole this sig from someone cleverer than me.
This is so obviously a set up. Liu was planted by the Chinese government to assist in the three steps to dominion of the deep...
Step 1: Trick the United States into removing sonar from their subs and replacing it with sensors imitating the lateral lines of fish.
Step 2: Build Chinese submarines with emourmous mouths and "Hyper Active Sonars" that mimmicks the sonar of the dolphins.
Step 3: Use said H.A.S. to stun the US submarines so they are easier to catch and eat, just as Dolphins do to fish.
I don't therefore I'm not.
All I asked for was sharks with frickin' lasers!
The problem with *AR is that it's not passive, therefore it's not stealthy as people can "hear" you looking; In Soviet Russia, Enemy finds your RADAR. This is an interesting development.
Me lost me cookie at the disco.
no doubt there is a former Sonar Shack operator that will say I don't know what I am talking about. he may be right, since I was A-gang Machinist Mate nuke school dropout, and not a STS ranker. but then again, I'll go up against him anyday on ship operation qualifications.
I'm good with numbers -
Our new lateral line-using fish overlords.
Thousands of hits here
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
Comment removed based on user account deletion
My (not topic-educated) thought process on this:
I would think this involves massive matrix-style calculations that cross-reference the detection of every sensor into creating a virtual 'object' when detected by water pressure and movement. Water flows that go towards the ocean floor obviously do not approach the floor at a 90 degree angle before turning as they hit it, but are distorted some distance before hitting the floor. It should obviously be possible to 'feel' that water flows are distorted before they actually reach whatever is distorting them.
My question is whether you can do this for an object 50 or 100 meters away. It sounds rather implausible.
life-like texture ;_;
I guess the US Navy did too good a job of classifying SOSUS, it's now declassified as of the early 90's, after the end of the "cold war"; it used arrays on the ocean bottom employing passive sonar to detect Soviet submarines. It was highly successful, and had been in operation since the 1950's. The arrays were a series of hydrophones strung out in a approximate linear arrangement at an optimum depth. The arrays were able to determine the bearing of the sound source by the phase delay of the sound waves received, and triangulation from simulataneous detection by several stations, each with its own set of arrays. Depth, location, orientation, was all carefully planned to improve the signal-to-noise ratio to allow maximum detection capability. The accuracy of bearing determination (direction) was calibrated by US Navy ships towing a sound source, keeping a continuous record of time vs. ship's position, then comparing the ship's actual position with the SOSUS arrays data. SOSUS is now reincarnated as a research tool used by civilian oceanographers.
You are right about SOSUS. But why I was modded down to Offtopic by someone when I specifically addressed sonar usage by a submarine just shows that you can't make /. readers happy, especially the ignant ones.
I'm good with numbers -