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


Forgot your password?
Robotics Hardware

Robot Walks Like a Human, Requires No Power 195

MrSeb writes "Today's groundbreaking entry into the Uncanny Valley is a pair of mechanical, robot legs that are propelled entirely by their own weight: they can walk with a human-like gait without motors or external control. Produced by some researchers at Nagoya Institute of Technology in Japan, all the legs require for sustained motion (they walked 100,000 steps, 15km, over 13 hours last year) is a gentle push and a slight downwards slope. They then use same 'principle of falling' that governs human walking, with the transfer of weight (and the slight pull of gravity), pulling the robot into consecutive steps."

This discussion has been archived. No new comments can be posted.

Robot Walks Like a Human, Requires No Power

Comments Filter:
  • by Dunbal ( 464142 ) * on Tuesday October 25, 2011 @04:06PM (#37836024)
    Oh wait - small caveat - requires a downhill slope. In the next article we will discover that scientists create a ball that also rolls downhill forever without a power source. OK, maybe it's a feat of balance and engineering but come on...
    • Re: (Score:2, Funny)

      Damn, beat me to it. Even so: http://en.wikipedia.org/wiki/Slinky [wikipedia.org]
      • See also this [petratoysusa.com] and that [petratoysusa.com]. I've seen those around for years.

        To be even more reductive: wouldn't any sufficiently round rigid object achieve the same objective? Given a smooth enough surface, a drop of water can also pull this off (although the surface would also have to be hydrophobic).

        Distilled, this is a dynamic mechanical object reacting to gravity (as opposed to a static object like a ball). It's very nice, and I'm sure this implementation wasn't easy to pull off, but it's nothing new.
    • Re: (Score:3, Informative)

      by prefec2 ( 875483 )

      Well the slashdot post is misleading. It is not powerless, it uses gravity. The interesting thing is, that is uses human motion properties and no electrical power to stay in motion.

      • by Dunbal ( 464142 ) *

        It is not powerless, it uses gravity.

        No, it uses "slight gravity". We're given to believe that this object generates a frame of reference around it where gravity is some fraction of 9.8ms-2.

      • that is uses human motion properties and no electrical power to stay in motion.

        Oh? What happens if you take away the power to the treadmill?

    • +1. Others by now have posted an observation equivalent to yous, but you managed a quality first post.
  • If it weren't for a recent episode of Mythbusters that showed that humans need external directional cues to maintain their own guidance (otherwise we wander and circle without realizing it) I'd say I want to see this thing work on just two legs. But to work on two legs it would need external guidance, which would eliminate the untethered, unpowered aspect.

    So instead I'll say: okay, now make one that has a simple motor that can walk up that slope indefinitely.

    • Re:Fascinating. (Score:4, Interesting)

      by Dunbal ( 464142 ) * on Tuesday October 25, 2011 @04:10PM (#37836094)
      Actually the human part has more to do with the way we're wired and with one side being more dominant than the other (and thus having both faster nerve conduction and stronger muscles than the other side), than actual engineering. You could build a perfectly symmetrical object and I guess the only things that would knock it off course are wind, thermal effects and the Coriolis effect. You can't build a perfectly symmetrical human though.
      • Actually the human part has more to do with the way we're wired and with one side being more dominant than the other

        Do you know why that is? I understand why my right arm is more powerful than my left, because I use it for more things. I don't understand why my left leg is more powerful than my right.

        • by xlsior ( 524145 )
          Do you know why that is? I understand why my right arm is more powerful than my left, because I use it for more things. I don't understand why my left leg is more powerful than my right.

          One of your legs tends to be dominant too, although it may not look as obvious as it does with your hands.

          For example:
          - If you start paying attention, you'll probably find that you tend to land on the same leg each time you jump.
          - When sitting with your legs crossed, you tend to cross your legs in the same position, w
          • also, when standing still, with feet generally next to each other, and taking a step forward, you usually will lead with your dominant leg. (that leg moves forward first)
      • by blair1q ( 305137 )

        No, the evidence from the Mythbusters showed that we wander in either direction. No consistency.

        They were convinced they were on track to their target the whole time, but somtimes went left, sometimes went right, sometimes both, sometimes making loops only a few meters in diameter.

        Fact is, without eyes or ears, we don't know we're veering from a straight path.

        Which makes a lot of sense, looking at it now.

        • by xlsior ( 524145 )
          No, the evidence from the Mythbusters showed that we wander in either direction. No consistency.

          During the Mythbusters experiment, they also showed them stating multiple times that they had the feeling they might be drifting slightly in a particular direction (even when this was not the case) -- Just 'compensating' for that feeling (whether consciously or not) would explain the seeming randomness to their wanderings.
      • Actually the human part has more to do with the way we're wired and with one side being more dominant than the other

        This was *sort* of covered in followup comments, but not exactly. It sort of sounds like you're talking about handedness/footedness or an analog thereof. At least on the Mythbusters episode, at least one of them was circling in *both* directions (i.e. a very wild path).

    • by Guspaz ( 556486 )

      The article (and you) are implying that adding power (even internal) defeats much of the purpose, and puts us into BIGDOG or ALPHADOG type territory; would there not still be a large efficiency gain over traditional walking robots, such that an internal power source is much more feasible than it would otherwise have been?

      • Thing is, this thing only seems to be efficient in a very narrow scenario. When we stand up, we're in a very unstable equilibrium. It's like leaning back in your chair; you can balance it nicely for a bit but it will always fall one way or the other. Our muscles, eyes, inner ear, etc work constantly to make sure we stand up straight. We use the same concept to make robots that can balance on a single wheel (see Inverse Pendulum). It's a great exercise in feedback control.

        Now this robot is in the same unstab

        • by blair1q ( 305137 )

          Er, I think they fixed the ankle just to simplify the thing. Shouldn't be impossible to replace it with a pantograph and get a similar result.

          • Sure but that still doesn't mimic the human ankle. If you want a robot with the same mobility as a human, you need to engineer it to meet or exceed our capability. A simple ankle will never do for a general purpose bipedal robot in our environment. Demonstrate for me a passive robot walking down a rocky incline instead of a smooth treadmill and I'll be more impressed. As it stands the machine is simply built to fit its controlled environment, but it can't fit in our environment.
            • by blair1q ( 305137 )

              Well, none of this thing really mimicks a human. Our stability is 100% due to muscular action under balanced tension, not static mechanical linkages that maintain orientation regardless of force.

              But, what they have is a good platform for making something that can modulate its stability without a lot of computation.

              But, it's somewhat less impressive than your average strandbeest [strandbeest.com].

            • A good percentage of people don't even see a rocky incline for months or years on end. And pretty much everywhere we go there's already flat accessibility for anyone that might be in a wheelchair.

              That's not to say they don't have a ways to go with this thing. That demo of the guy with the walking contraption on doesn't look practical.
        • by chrb ( 1083577 )

          To accommodate all the variety of our environment, we've evolved many degrees of freedom in our foot, ankle, pelvis, etc. So, if we want a robot that can do the same degrees of tasks as us, we need to add back those degrees of freedom to this robot, which in turn will make it fall over, thus defeating its purpose.

          The point of the robot is to develop low-energy gaits similar to those that humans use. They can add the extra stuff back in and still maintain the same gaits. Why would it fall over? We don't.

        • by hitmark ( 640295 )

          I think there is a video out there of a robot able to balance two sticks on top of each other by just moving the base.

    • humans need external directional cues to maintain their own guidance (otherwise we wander and circle without realizing it

      Hmmm I wonder if having a tail would correct that....
      -looks at sleeping neighbor and stapler-

    • Come on now, it is not that brilliant??

      I have heard of reinventing the wheel (around 9000bc) but this is ridiculous?

      We are reinventing walking now?! (200,000BC)

      (Can I take my tongue out of my cheek?)

    • > But to work on two legs it would need external guidance

      The hill provides guidance.

      • by blair1q ( 305137 )

        A little. If it's steep enough. If it's gradual and there's interstitial unevenness, you'll never know which way is up or down.

  • He made a set of wooden walking bipedal mice for my father when he was a boy.

    It was less impressive. But gravity powered walking toys have been around for decades.

    • by savuporo ( 658486 ) on Tuesday October 25, 2011 @04:37PM (#37836556)
      No kidding. A random article from 2005
      http://www.world-science.net/othernews/050217_robotfrm.htm [world-science.net]
      But researchers at Cornell University in New York State, the Massachusetts Institute of Technology (MIT) and Holland’s Delft University of Technology have built robots that seem to more closely mimic the human gait -- and the Cornell robot matches human efficiency, their designers say. The researchers’ inspiration: simple walking toys that fascinated children in the 19th century.
      Researchers at each of the three universities have built walking robots, differing slightly but based on the same principle. They are an extension of several years of research into “passive-dynamic walkers” that walk down a shallow slope, very much like simple walking toys that have been around since the 1800s and developed more scientifically starting in 1988.
    • Same thought - I remember toys like this in my cereal boxes as a kid. They walk down a slant as long as it's neither too shallow or too steep.
    • by EdZ ( 755139 )
      Yep, the type of robot in general is known as a 'passive dynamic walker', as it is dynamically stable (moves without falling over, falls over when not moving), and does not require active stabilisation. There are 3/4 legged versions, like the one in the video, 2-legged versions that 'waddle', and 2-legged versions with counterweighted arms that minimise (but not eliminate) the waddle.
  • by tsa ( 15680 ) on Tuesday October 25, 2011 @04:13PM (#37836152) Homepage

    It does require power, namely gravitational energy.

    • It does require power, namely gravitational energy.

      power : rate :: energy : quantity

    • by Rary ( 566291 )

      It does require power, namely gravitational energy.

      And a push. And, if you watch the video, someone standing by to stop it from falling over.

      Give me a long enough sloped surface, and I'll show you a ball that can go even further, without falling over, and with no need for a push.

      This is just an old child's toy embiggened and made out of aluminum.

    • Yep, it's a fancy Slinky.

  • Groundbreaking? (Score:5, Informative)

    by Missing.Matter ( 1845576 ) on Tuesday October 25, 2011 @04:17PM (#37836218)

    I've seen this kind of design before. In fact, you can make it yourself: http://www.instructables.com/id/How-to-Build-A-Walking-Robot---Passive-Walker/ [instructables.com]

    Some other prior art: http://www.andrew.cmu.edu/user/shc17/Passive_Robot/PassiveRobot_photos.htm [cmu.edu]

    Obviously this is probably much better in certain ways but it's tough to call this thing groundbreaking

    • While I respect their accomplishment, I agree, I wouldn't call it "groundbreaking." Of course, very little academic research actually is.

      The same goes for other areas of society. Gutenberg wasn't the first to use movable type; Columbus wasn't the first European to make it to the New World; Taylor and MacLaurin weren't the first to use their eponymous expansions; Jacobi, it turns out, scooped the Hungarian Algorithm (but his manuscript was lost until recently); the Ming dynasty had clocks with mechanical e

      • Of course, I won't deny them the credit they deserve. Their system looks well engineered. And in their defense obviously the writer of the article is using the term "groundbreaking"

        But at the same time I don't see a paper anywhere and I don't see any citations on prior work so this sort of thing should really be noted. This is especially true in an area like robotics (my field) where terms like innovative and groundbreaking get thrown around a lot. When really, it's just a rehash of an idea used in another

        • This is especially true in an area like robotics (my field) where terms like innovative and groundbreaking get thrown around a lot. When really, it's just a rehash of an idea used in another discipline applied to robotics.

          Yeah, I know the feeling.

          Even great, celebrated, actually-(somewhat)-useful ideas turn out to be simple applications of other ones. Take the Kalman Filter. If you come at it from a least-squares point of view and focus on the word "optimal" -- as it was first explained -- it sounds extremely impressive. But if you explain what a Bayes Filter is (after which people say, "ok, that's simple enough"), and then specialize it to Gaussian noise and linear systems (again to the reaction "ok, that's easy"), you'v

    • It's especially hard to call it groundbreaking when it requires a guy standing next to it touching it every few seconds. I don't think he left it alone for more than about 5 seconds, and the attention was a little unnerving. Is it really that fragile?
      • I thought that myself when I started watching the video. If you keep watching, there's a shot of it walking perfectly fine all alone, and it's stated that it's walked unaided for something like 32 hours straight. It wasn't smart of them to start with that shot, though. If you're not patient enough to watch it through, you really get the impression that it can't walk without someone catching it every few seconds.

  • Please! (Score:5, Insightful)

    by Grizzley9 ( 1407005 ) on Tuesday October 25, 2011 @04:19PM (#37836244)
    Stop calling these robots! Do you call Newton's Cradle [wikipedia.org] a robot as well? What about the Drinking Bird [wikipedia.org] or even the common Slinky? Just b/c it has a shape that is in two pieces like a leg does not a robot make, esp one that relies on gravity to perform any motion.
  • I guarantee this will become an extreme sport within a year. Either a special olympics event or perhaps horse jockeys. Or maybe full size physically healthy people doing some kind of ultra extreme surfing thing.

    Would I run down a hill as fast as I can on my own two feet? No thats crazy, I would twist an ankle or a knee, maybe permanent damage... But if that were a robot ankle or robot knee, and I had enough dollars for sponsorship not to worry about it...

    There are also military defense issues. If you co

  • by Sarten-X ( 1102295 ) on Tuesday October 25, 2011 @04:24PM (#37836348) Homepage

    This is [youtube.com] old news [umich.edu].

  • Passive walkers have been around for a long time. There was a fad for studying them a few years back, but it didn't lead to anything. The important issues in legged locomotion all involve handling difficult terrain. On flat surfaces, wheels work better.

  • Sure, it's a start, and it's cool . . . but I would have been more amused if they had build a massively parallel array of Slinkys instead. Maybe a Buckyball shaped scary looking thingie with cameras and minimal remote direction control.

  • All it needs is a gentle push and a downward slope?

    So they made a two legged thing that duplicates what a wheel can do? How about trying to do better than an 6,000 year old invention. Yes, the engineering to get a two legged machine to duplicate what a wheel can do is interesting, but I would expect a high school kid to be able to do that.

  • by Oswald McWeany ( 2428506 ) on Tuesday October 25, 2011 @04:47PM (#37836682)

    AHA! I have found the plot for my great sci fi novel.

    Alien robots land on mountain tops all around the world... they start marching down- destroying all life as we know it- they appear indestructible- mankind is doomed...

    Until mankind discovers their fatal flaw... they can only walk downhill.

  • http://www.strandbeest.com/ [strandbeest.com]

    Found this guy mentioned in a forum once, turns out he lives at walking distance from me. I think it's the coolest thing ever.

  • Jesus, I'm much drunker than I thought.
  • If I put a rolling pin on a treadmill on a downward slope, I achieve the same effect.

  • If it has no on-board power or control, does it make sense to call it a "robot"? It might be a useful demonstration of "simple legs we could put on a walking robot", and demonstrate that comparatively simple motive devices could move it in the same linear way that gravity does, but I think "robot" is stretching the envelope . . . on the bottom.
  • All without external power! Using only gravity!

  • They can only "walk like humans" if they can't walk in a straight line! They just tested out that 'myth' on mythbuster of humans not walking straight unless they can see where they're going. It was really interesting to see, even the swimming portion. If you haven't seen it, check it out:

    Premiere: Oct. 12, 2011

    Is it impossible for humans (without a point of reference) to walk in a straight line, such as when they're blindfolded? Will binary explosives, well, explode in the case of a fender bender? The MythBusters are on the case.


  • http://www.youtube.com/watch?v=WR931mtC3l4 [youtube.com]

    I'm fascinated by all these kinds of mechanics.

  • Explains soulless zombie walking.

  • [insert rant here about the road to somewhere being "uphill both ways"]
  • http://www.wallaceandgromit.com/films/wrongtrousers/about.html [wallaceandgromit.com] Beware our walking leg overlords!

"More software projects have gone awry for lack of calendar time than for all other causes combined." -- Fred Brooks, Jr., _The Mythical Man Month_