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Scientists Discover How To Stop Luggage From Toppling On the Race Through the Airport (theguardian.com)

An anonymous reader quotes a report from The Guardian: Scientists have worked out why suitcases tend to to rock violently from one wheel to the other until they overturn on the race through the airport. This most pressing of modern mysteries was taken on by physicists in Paris, who devised a scale model of a two-wheeled suitcase rolling on a treadmill and backed up their observations with a pile of equations and references to holonomic restraints, finite perturbations and the morphing of bifurcation diagrams. Fortunately for non-physicists, the findings can be reduced to simpler terms. For the suitcase to rock it had to hit a bump or be struck in some other manner; the faster the suitcase was being pulled, the more minor the bump needed to set it off. So far, so obvious. But Sylvain Courrech du Pont wanted to know more. Why did a rocking suitcase swerve and make such violent movements that it might eventually topple over? After more treadmill tests and more equations, the answer popped up: because a suitcase's handle pulls from the middle and the wheels are at its sides, the suitcase swerves inwards whenever it tilts up on one wheel. If the rocking overcomes the dampening effect that happens when each wheel touches the ground again, the suitcase will keep on rocking or eventually flip over. In conclusion, the researchers discovered that "when a suitcase starts to rock out of control, the correct response is not to slow down but to pull it faster." The scientists have published their findings in the journal Proceedings of the Royal Society.

7 of 183 comments (clear)

  1. This is new? by Solandri · · Score: 4, Interesting

    People who tow trailers have known about this for decades.

  2. Move the handle by viperidaenz · · Score: 4, Informative

    The handle is also on the same side as the wheels, so when you're pulling it along the weight is above the pivot point between the wheel still on the ground and your hand.
    If the handle was on the opposite side from the wheels the weight wouldn't be as high (it would be more in line with your hand and the wheel), so the suitcase would be more stable.

  3. Re:Or just get one that has 4 wheels by mnemotronic · · Score: 4, Funny

    Mine has 11.

    --
    The Russians have won. They have made the world a cesspool of distrust, greed, fear and hate.
  4. Re:Just like trailers by Sir+Holo · · Score: 4, Informative

    As I just posted below - before seeing your comment - those idiots need to hit the accelerator when the trailer starts swerving! Any other maneuver is bound to lead to a bad day.

    Speeding up does work.

    A second technique that works is to put the car in neutral, effectively decoupling the travel-direction forces transmitted through the hitch. With no more tugging it along, the trailer will settle down (this stops any more energy from being put into the trailer's motion, letting roll-resistance quench out the speed and oscillations). I have done this. Just decouple and coast.

    You are correct that hitting the brakes is the absolute worst thing that the driver can do.

  5. Is anyone running through airports in 2017? by 93+Escort+Wagon · · Score: 4, Insightful

    I would think that would get you shot, nowadays.

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  6. Re:Just like trailers by sconeu · · Score: 4, Informative

    I was about 10.... We were on the way home from a camping trip, and my mom was driving.

    Some asshole cut her off, and she instinctively hit the brake. My dad was yelling at her to hit the gas... to no avail. We jacknifed and flipped. That's stuck with me ever since. If your trailer is out of control, speed up.

    --
    General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  7. Re:Or just get one that has 4 wheels by ad454 · · Score: 5, Insightful

    Not all women are weightlifters.

    Most including myself have difficulties carrying nearly 23 kg (50 lb) over long distances quickly, through public transit, long sidewalks, crowded places, etc., along with a separate carryon.

    Keep in mind that when is travelling overseas for a month or more, in strange and undeveloped places, with different dress codes, and in different climates, you need to carry a lot with you that you cannot easily buy there. Not to mention that the custom in many places to bring thoughtful gifts from your home.