Stories
Slash Boxes
Comments

SoylentNews is people

posted by janrinok on Friday September 10, @02:15AM   Printer-friendly
from the rock-and-roll dept.

Walking with coffee is a little-understood feat of physics: Understanding the physics behind natural processes provides new applications for soft robotics, manufacturing automation:

The coffee, a thermally agitated fluid contained in a cup, has internal degrees of freedom that interact with the cup which, in turn, interacts with the human carrier.

"While humans possess a natural, or gifted, ability to interact with complex objects, our understanding of those interactions -- especially at a quantitative level, is next to zero," said ASU Professor Ying-Cheng Lai, an Arizona State University electrical engineering professor. "We have no conscious ability to analyze the influences of external factors, like noise or climate, on our interactions."

Yet, understanding these external factors is a fundamental issue in applied fields such as soft robotics.

"For example, in design of smart prosthetics, it is becoming increasingly important to build in natural modes of flexibility that mimic the natural motion of human limbs," said Brent Wallace, a former undergraduate student of Lai's and now a doctoral student in ASU's Ira A. Fulton Schools of Engineering. "Such improvements make the prosthetic feel more comfortable and natural to the user."

According to Lai, it is conceivable that, in the not-too-distant future, robots will be deployed in various applications of complex object handing or control which require the kind of coordination and movement control that humans do quite well.

If a robot is designed to walk with a relatively short stride length, then relatively large variations in the frequency of walking are allowed. However, if a longer stride is desired, then the walking frequency should be selected carefully.

A new paper published in Physical Review Applied, "Synchronous Transition in Complex Object Control," originated with Wallace as part of his senior design project in electrical engineering, supervised by Lai. Wallace has received an NSF Graduate Fellowship and now is a doctoral student in ASU's School of Electrical, Computer and Energy Engineering.

The ASU team's research expands on a ground-breaking, virtual experimental study recently conducted by researchers at Northeastern University, using the coffee-cup-holding paradigm and adding a rolling ball, to examine how humans manipulate a complex object. Participants deliberately rotated the cup in a rhythmic manner with the ability to vary force and frequency to ensure the ball stayed contained.

The Northeastern study showed that the participants tend to select either a low-frequency or a high-frequency strategy -- rhythmic motion of the cup -- to handle a complex object.

A remarkable finding was that when a low-frequency strategy was used, the oscillations exhibit in-phase synchronization, but antiphase synchronization arises when a high-frequency strategy was employed.

Journal Reference:
Brent Wallace, Ling-Wei Kong, Armando Rodriguez, et al. Synchronous Transition in Complex Object Control, Physical Review Applied (DOI: 10.1103/PhysRevApplied.16.034012)


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
(1)
  • (Score: 4, Interesting) by Rosco P. Coltrane on Friday September 10, @03:35AM (6 children)

    by Rosco P. Coltrane (4757) on Friday September 10, @03:35AM (#1176485)

    This is quite well known: if you hold a cup of coffee while walking and the liquid starts to move and is about to spill over, immediately change the pace of your stride and it'll stop. You have to catch it quick though, because as soon as it enters resonance, it goes fast.

    My personal habit is to grab the cup from the coffee machine and watch it for the first 2 or 3 steps. If the coffee inside the cup stays more or less still, I just keep walking at that pace and never look at it again.

    Also, keep your arm loose to decouple the cup from your body's movements as much as possible. I.e. turn your arm into a kind of steadycam mount.

    • (Score: 0) by Anonymous Coward on Friday September 10, @11:49AM (3 children)

      by Anonymous Coward on Friday September 10, @11:49AM (#1176566)

      Reducing interference effects helps, but more generally just isolation. When I ealkwith xoffee, the coffee has a trajectory in space, and I fit myself underneath and around the coffee.

      Same as shooting on the move or a spoon and egg rest. You isolate that limb, and yout brain does the inverse kinematics to put you in place below it.

      • (Score: 0) by Anonymous Coward on Friday September 10, @11:52AM (2 children)

        by Anonymous Coward on Friday September 10, @11:52AM (#1176567)
        I should mention, the same is also taught to fencers. You move with your head "hanging" from a rail so the foil and your movement is smooth and quick.
        • (Score: 0) by Anonymous Coward on Friday September 10, @03:48PM (1 child)

          by Anonymous Coward on Friday September 10, @03:48PM (#1176662)

          Funny similar thing. When I started practicing aikido, I stopped spilling coffee when walking. When one part of your body is held, you train to (mostly) surrender it and consider it already immobilized. You're up against someone stronger than you, after all. Then move the rest of your body around that point. I guess I'm pretending the coffee is holding me? or something.

          • (Score: 0) by Anonymous Coward on Friday September 10, @08:43PM

            by Anonymous Coward on Friday September 10, @08:43PM (#1176793)

            Cubert J. Farnsworth : I understand how the engines work now. It came to me in a dream. The engines don't move the ship at all. The ship stays where it is, and the engines move the universe around it.

    • (Score: 2) by everdred on Friday September 10, @03:40PM

      by everdred (110) Subscriber Badge on Friday September 10, @03:40PM (#1176657) Homepage Journal

      turn your arm into a kind of steadycam mount

      This is the exact metaphor I've used when trying to explain how to securely hold a cup of coffee as a passenger in a car. If you tense up as the car goes over a bump you just transmit the shock. And for a full cup, you're better off with a loose arm than a cupholder.

    • (Score: 0) by Anonymous Coward on Friday September 10, @09:24PM

      by Anonymous Coward on Friday September 10, @09:24PM (#1176799)

      Also, keep your arm loose to decouple the cup from your body's movements as much as possible. I.e. turn your arm into a kind of steadycam mount.

      I find it's best to hold the cup in your non-dominant hand, so in your left hand if you're right-handed.

  • (Score: 5, Interesting) by MostCynical on Friday September 10, @04:14AM (9 children)

    by MostCynical (2589) on Friday September 10, @04:14AM (#1176487) Journal

    Walking With Coffee is a Little-Understood Feat of Physics

    Try having the robot walk with a pint of beer after drinking five..

    --
    “I've learned from experience that asking politely never works unless you have the upper hand.” Daisuke Aramaki, GIS:SAC
    • (Score: 2) by c0lo on Friday September 10, @05:48AM (8 children)

      by c0lo (156) Subscriber Badge on Friday September 10, @05:48AM (#1176501) Journal

      after drinking five..

      I don't get it. Why stop at five?
      If you have a beer serving robot, why couldn't it ingest the whole keg and then regurgitate a perfect pint at the table?

      --
      https://www.youtube.com/watch?v=aoFiw2jMy-0
      • (Score: 5, Funny) by pTamok on Friday September 10, @06:39AM (2 children)

        by pTamok (3042) on Friday September 10, @06:39AM (#1176513)

        Marvin would be perfect for serving bitter.

        • (Score: 2) by c0lo on Friday September 10, @07:45AM (1 child)

          by c0lo (156) Subscriber Badge on Friday September 10, @07:45AM (#1176524) Journal

          Now, you're depressing me.

          --
          https://www.youtube.com/watch?v=aoFiw2jMy-0
          • (Score: 0) by Anonymous Coward on Friday September 10, @07:06PM

            by Anonymous Coward on Friday September 10, @07:06PM (#1176751)

            Stuck in a 1 bedroom flat for 22 hours a day isn't fun but you're never far from the fridge and you can use that 2 hours exercise walking to a bottleshop but in my wowser LGA they don't allow open carry to drink one on the way home.

            #lockdown

      • (Score: 2) by MostCynical on Friday September 10, @07:11AM (4 children)

        by MostCynical (2589) on Friday September 10, @07:11AM (#1176518) Journal

        after 6 pints (and double scotch chasers) it is all I can do to stagger to a car.. no way I am going to attempt to carry a beer .. and I wouldn't want to make a robot do it, either!

        --
        “I've learned from experience that asking politely never works unless you have the upper hand.” Daisuke Aramaki, GIS:SAC
        • (Score: 2) by Freeman on Friday September 10, @01:45PM (3 children)

          by Freeman (732) on Friday September 10, @01:45PM (#1176599) Journal

          Thankfully, you're getting in the back seat or passenger's seat. Right?

          --
          Forced Microsoft Account for Windows Login → Switch to Linux.
          • (Score: 0) by Anonymous Coward on Friday September 10, @07:15PM (1 child)

            by Anonymous Coward on Friday September 10, @07:15PM (#1176754)

            We call that Dutch Courage, and then some.

            Naturally after all that social lubricant, the ladies are just in awe of his drinking prowess and eager to give him a ride at their place.

            • (Score: 2) by MostCynical on Friday September 10, @08:14PM

              by MostCynical (2589) on Friday September 10, @08:14PM (#1176782) Journal

              Man, being reasonable, must get drunk; The best of life is but intoxication.

              Don Juan Lord Byron

              --
              “I've learned from experience that asking politely never works unless you have the upper hand.” Daisuke Aramaki, GIS:SAC
          • (Score: 3, Funny) by MostCynical on Friday September 10, @08:11PM

            by MostCynical (2589) on Friday September 10, @08:11PM (#1176781) Journal

            absolutely..
            need to be that drunk to let one of my freinds drive me home (terrible driver!)

            --
            “I've learned from experience that asking politely never works unless you have the upper hand.” Daisuke Aramaki, GIS:SAC
  • (Score: 2) by Dr Spin on Friday September 10, @08:06AM

    by Dr Spin (5239) on Friday September 10, @08:06AM (#1176529)

    A remarkable finding was that when a low-frequency strategy was used, the oscillations exhibit in-phase synchronization, but antiphase synchronization arises when a high-frequency strategy was employed.

    Shock horror - the wavelength of the resonant frequency remains constant, while the wavelength of the frequency of motion does not.

    Most people who have been on a boat would know that.

    In all probability, most people who known what wavelength is would know that.

    --
    Warning: Opening your mouth may invalidate your brain!
  • (Score: 2) by SunTzuWarmaster on Friday September 10, @12:13PM

    by SunTzuWarmaster (3971) on Friday September 10, @12:13PM (#1176580)
    Obligatory shout-out to my favorite research paper of all time: https://www.sciencedirect.com/science/article/pii/S2078152015300377 [sciencedirect.com]
(1)