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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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Octopus is food! If there is any inspiration it'd be gene-modified giant octopus with lovely meat! How can people possibly watch food all day long and just make swimming robots?!
Octopusses aren't that fast. Its squids that can move fast
On one hand, I'm happy for these discoveries because they will benefit us, but on the other hand, I know US military will find some way to use this technology to hurt other people.
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.
Nuclear subs are not designed to maximize (speed / body length). If they were they wouldn't be so long and narrow. They wouldn't have all that extra space for stuff like crews and missiles and radar. They wouldn't have thick, pressure-resistant (and heavy) hulls. They would just be a super short hull with an oversized engine attached. So this comparison is stupid.
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!
The militias are important because of certain feels I have against even this type of story. I know this. It is ideal. Please do not discard stuff. It will certainly bother the octopus'.
-Slink3r
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.
Anyone could have told you, bio-mechanics are the way to go.
now i'm scared
Remember kids, if you're not paying for the service, YOU ARE THE PRODUCT THAT IS BEING SOLD.
ribbed or vibrating?
This reminds me of the Rocket Differential Equation. A Rocket loses mass as it goes burning fuel. This mean the thrust is using less and less weight as it goes.
This octopus robot is not only losing mass, it's also reducing drag! The head goes from a wide egg shape to thin arrow as it loses the propellant (water).
This is really neat!
... 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).
I've seen enough hentai to know where this is going...
the marketing department of the Sirius Cybernetics Corporation however defines a robot as
"Your Plastic Pal, who's fun to be with"
There you go
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.