Like A Cat, New Robot Lands On Its Feet

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Like A Cat, New Robot Lands On Its Feet

Posted by timothy on Wednesday July 14, 2004 @05:21AM from the pfffthhpt dept.

eckenheimer writes "Students at the Physics Department at Drury University have developed a robot that uses motions and contortions of its body to orient itself in zero gravity. According to the project site, 'If you've ever seen a cat land on its feet after falling while upside down then you've seen the idea behind our project.' The effort is a proposal for the NASA Reduced Gravity Student Flight Opportunities Program."

17 of 263 comments (clear)

Like a...? by SIGALRM · 2004-07-14 05:21 · Score: 5, Funny

If you've ever seen a cat land on its feet after falling while upside down
I'm looking forward to their "like-a-dog" model: word on the street is, licks its own ass.

Now that's using "motions and contortions".

--
Sigs cause cancer.
1. Re:Like a...? by grunt107 · 2004-07-14 05:26 · Score: 5, Funny
  
  I would merge the cat/dog projects.
  
  All the loyalty of a cat with the cleanliness of a dog
2. Re:Like a...? by Rei · 2004-07-14 05:46 · Score: 4, Interesting
  
  There are serious applications for this. Namely, being able to orient yourself in space without using propellant is a very valuable ability.
  
  The real surprise is that this is nothing radical; I really don't get why it deserves a press release. Probes have been using momentum wheels, for example, to do the same thing for decades. What is the big advantage of this over, say, a small set of momentum wheels? All I can really say about it is that it's more complex, and seems more likely to wear and have part failures.
  
  --
  Very well; let this abomination unto the Lord begin!
3. Re:Like a...? by drtomaso · 2004-07-14 05:49 · Score: 4, Funny
  Some other "cat-like" behavior they forgot to mention:
  
  Robot sleeps 16 hours a day
  
  Robot begs for food when scientists are seated around the dinner table
  
  Ate robo-bird
Now all we need is buttered bread by Anonymous Coward · 2004-07-14 05:22 · Score: 5, Funny

...to stick on its back and we'll have an antigravity engine.
Cats landing on their feet by thedogcow · 2004-07-14 05:25 · Score: 4, Informative

This was explained to me in my physics for engineers class...

Cats reposition themselves to land on their feet because they can sense the change in velocity (dv/dt = acceleration). My professor stated this only works for small height values (less than 20 ft), otherwise, the acceleration due to gravity might result in an unpleasant aftermath.

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Yes! I listen to NYC Speedcore and do math at 3AM. I suggest you try it too.
1. Re:Cats landing on their feet by Rob+Carr · 2004-07-14 05:36 · Score: 5, Interesting
  
  Cats reposition themselves to land on their feet because they can sense the change in velocity (dv/dt = acceleration). My professor stated this only works for small height values (less than 20 ft), otherwise, the acceleration due to gravity might result in an unpleasant aftermath.
  Actually, it's the short falls that tend to kill cats. Cats (like skydivers) can assume a position that reduces the terminal velocity and presents the greatest surface area for impact, reducing the force per unit of surface area. It takes a while to rotate and get into the position, so if the fall is too short, the cat will land in an awkward position and is far more likely to die.
  This is not to say that the cats that fell from a great height were uninjured - just that they were more likely to have non-fatal injuries.
  
  --
  This sig seemed like a good idea at the time....
2. Re:Cats landing on their feet by captnjameskirk · 2004-07-14 05:42 · Score: 5, Funny
  
  the acceleration due to gravity might result in an unpleasant aftermath
  
  Actually, it's the deceleration when meeting the ground that is usually the culprit.
3. Re:Cats landing on their feet by no+longer+myself · 2004-07-14 05:48 · Score: 5, Funny
  
  I'm just having this morbidly funny image of people throwing cats out windows as part of a government study to test that "statistic":
  "Damn, Bob... Did you see that? He might have made it if that cab driver hadn't run over him."
  "Yeah, Pete. Let's take this tabby up to the 23rd floor. Oh, by the way, did you hear they're working on a robot that mimics this sort of behavior."
  "I think I did read something about that, Bob, but tossing an expensive piece of hardware out the window just isn't as satisfying."
  "You've never owned a Mac, have you, Pete?"
4. Re:Cats landing on their feet by eunos94 · 2004-07-14 05:54 · Score: 5, Insightful
  
  I call bullshit. This study has one HUGE flaw in it. I remember in college when this study was brought up in a statistics class. The flaw can be summed up in one clear thought.
  "No one brings a clearly dead cat to the vet."
  If the fall is high enough, the odds of living decrease and therefore no cats are brought to the vet unless they miraculously survived. The study self-selects for those cases. Ergo...bad stats. Grrr...the bane of my social sci existence.
Have to wonder how they did their research... by foidulus · 2004-07-14 05:27 · Score: 4, Funny

I can just imagine the papers you would have to fill out
Experiment: "Drop cats repeatedly, observe results for use in robotics..."
See how well PETA would love that one!
Re:Where's the beef? by enforcer999 · 2004-07-14 05:33 · Score: 5, Informative

Here you go. It is not a very "pretty" robot but it could have its uses.
I wonder... by Unnngh! · 2004-07-14 05:39 · Score: 4, Interesting

...if the robot can survive terminal velocity falls like cats. Cats falling from very high heights (i.e. skyscrapers) tend to survive the fall better than those falling from lower elevations.
Story Musgrave by Ferante · 2004-07-14 05:53 · Score: 5, Interesting

In grad school one of my physics professors wrote a paper on orienting onself in zero g with no net angular momentum. One student was just convinced it was impossible. Soon thereafter we were visted by Story Musgrave (one of astronauts who fixed Hubble) and the professor told him of the paper. Story immediately sat down on a swivel chair and demonstrated the motion necessary to turn in zero g without grabbing on to anything. It's interesting how a concept that caused some interesting debates among the students suddenly became obvious when it was directly demonstrated.
Zero G? by Shabbs · 2004-07-14 05:58 · Score: 4, Funny

Just curious... how does something "fall" in zero g? Doesn't falling imply gravity?

What would a cat do in Zero G? Would it continously try to adjust itself.

Now THAT would be funny to see.

Cats in spce... the next fontier.

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Mark
Re:doesnt work by Lord+Bitman · 2004-07-14 06:05 · Score: 5, Insightful

do the math you twit. Perpetual motion is still impossible because toast doesnt care what side it lands on when it's already got fur all over it.

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-- 'The' Lord and Master Bitman On High, Master Of All
RGSFOP by ghack · 2004-07-14 06:31 · Score: 5, Informative

As an individual who has participated in the RGSFOP program, I have seen a number of novel experiments, but this particular experiment is a retread that has been done many, many times. Last March, for example, Washington-St. Louis did a very interesting experiment involving zero-gravity orientation of a space vehicle. The typical RGSFOP experiment fails, however, although my University did experience a success this year.

A list of active RGSFOP teams