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Octopus-Inspired Robot Matches Real Octopus For Speed
KentuckyFC writes: Underwater vehicles have never matched the extraordinary agility of marine creatures. While many types of fish can travel at speeds of up to 10 body lengths per second, a nuclear sub can manage a less than half a body length per second. Now a team of researchers has copied a trick used by octopuses to build an underwater robot capable of matching the agility of marine creatures. This trick is the way an octopus expands the size of its head as it fills with water and then squirts it out to generate propulsion. The team copied this by building a robot with a flexible membrane that also expands as it fills with water.
The fluid then squirts out through a rear-facing nozzle as the membrane contracts. To the team's surprise, the robot reached speeds of 10 body lengths per second with a peak acceleration of 14 body lengths per second squared. That's unprecedented in an underwater vehicle of this kind. What's more, the peak force experienced by the robot was 30 per cent greater than the thrust generated by the jet. The team think they know why and say the new technique could be used to design bigger subs capable of even more impressive octopus-like feats.
The fluid then squirts out through a rear-facing nozzle as the membrane contracts. To the team's surprise, the robot reached speeds of 10 body lengths per second with a peak acceleration of 14 body lengths per second squared. That's unprecedented in an underwater vehicle of this kind. What's more, the peak force experienced by the robot was 30 per cent greater than the thrust generated by the jet. The team think they know why and say the new technique could be used to design bigger subs capable of even more impressive octopus-like feats.
um... that's not a robot, its a balloon stretched over a turkey baster.
After reading TFA all they effectively did was design a toy-sized torpedo that uses an expanding membrane to hold the liquid used to propel the device. Nada más.
While they probably did do interesting work in fluid dynamics (IANAFD), in no way, shape or form could this even be remotely considered a robot.
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Ssshhh -- before a vegan hears you.
My first program:
Hell Segmentation fault
Octopusses aren't that fast. Its squids that can move fast
Can't wait for nuclear-powered giant octopus submarines. Beats a laser-sporting shark anyday !
Maybe we deserve this world ?
I'm not completely sure because definitions change all the time, but I'm fairly certain that an underwater stored-energy balloon toy fails to meet even the loosest definition of "robot".
Scruting the inscrutable for over 50 years.
. . . Welcome our Robotic Octopi Overlords!
...why divers pee in their wetsuits. It helps them swim faster.
Speaking on behalf non-militant vegetarians ... no, you really should be sure a vegan hears you, because it's usually hilarious to hear the squealing. ;-)
I'm that vegetarian that says "I hear the calamari here is awesome, you should try it". :-P
Lost at C:>. Found at C.
What a nice sub - go from 10Gs back to 0Gs every couple of seconds. I'm sure the sailors will be shaped differently after traveling in that thing for a couple of weeks.
Do you have ESP?
Creatures that use this form of population do it only for "bursts" - like to escape a predator. They cannot sustain this speed. If they used this form of propulsion for a submarine, that would be one hell of a jerky ride.
The post says, "While many types of fish can travel at speeds of up to 10 body lengths per second, a nuclear sub can manage a less than half a body length per second."
How big are these fish? Body length does not seem like a good measure of speed, as it would tend to favor smaller fish over larger fish. There is no fish that is anywhere close to a sub in length (362' or 110 m is a reasonable size--ten times the longest fish). Even if you include whales (aquatic but not fish), the blue whale is less than a third the length of the typical submarine. A blue whale can't even go three body lengths per second, much less ten. Yet the submarine is still faster than a blue whale, although it can only go half a body length per second.
Let's not diminish the power of a good plate of lentils or beans!! That's turbo power if you can get it to go off the wetsuit through the leg openings!
10 times body length per second is impressive on its own for under water bodies. I suspect the reason is the shrinking of the head as water is ejected out of the nozzle as it moves. In underwater craft, the vehicle has to displace the fluid around it, make room for itself and then occupy that space as it moves forward. Water is incompressible for all practical purposes. Water is a very heavy fluid, 1000 times the density of air ( 1 Kg/m^3 for air, 1000 Kg/m^3 for water). It takes lots of power to set that much of water in motion to move it out of the way. But octopi have an unusual mode of propulsion, its head will fill with water slowly and then when it moves its head is shrinking, it does not have to move that much water out of the way as it moves forward. That probably accounts for the relative speed.
Again, it is impressive for an octopi with tiny brains capable of just predicting football match winners. They could not have solved the Navier-Stokes equations and figured this out.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
The Encyclopedia Galactica defines a robot as
"a mechanical apparatus designed to do the work of a man."
I'll leave the ultimate zinger for somebody else...
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
That's ok. Marine creatures have never been able to match the capacity of underwater vehicles either. A nuclear sub can haul 140+ people around, fire torpedoes, and launch guided missiles simultaneously. Thankfully aquatic creatures are some distance away from being able to do any one of those things, let alone all of them.
....but its inferior to octopus when served on rice with wasabi.
now i'm scared
Remember kids, if you're not paying for the service, YOU ARE THE PRODUCT THAT IS BEING SOLD.
If you follow the links in TFA, you will find that they originally were trying to create a robot based on a different animal commonly used for food.
Unfortunately, the model they chose was based on the cow and it was an udder failure.
as long as they are trying to hurt the people trying to hurt me, i'm fine with it.
... sure, I'll believe it when I see an octopus-like apparatus come anywhere near mach 1. Until then we'll have supercavitation which actually is starting to perform (scarily).
Yeah, I had to read the last sentence three times because I thought it said, "...even more impressive octopus-like farts."
You shall see a cow on the roof of a cotton house.
Why are we concerned that a gigantic metal tube designed to transport people underwater and missiles/other weaponry does not travel as fast as an organic unit that does not transport personnel and ordinance?
In other news, School buses not as fast as F1 cars.