The Cubli; Laws of Motion and Angular Momentum at Play

Submitted by Charlton Stanley, Guest Blogger

Sir Isaac Newton

Ever since I was a kid, wheels, gears and spinning things held a fascination. I suspect that is true of most youngsters. One of my all time favorite Christmas toys was a gyroscope. When I took physics, my favorite subject was Mechanics, especially when I got to play with the lab equipment that demonstrated angular momentum and Newton’s laws of motion. I did a bit of  research on the history of the discovery of the laws of angular momentum and inertia. Seems Descartes first formulated it, then Newton used Descartes’ ideas in developing his Laws of Motion. When adding the discoveries of Newton and Descartes together, we get the Law of Conservation of Momentum. Several years after Newton published his Laws of Motion, Euler first wrote the formula F=ma.

The physical laws governing Mechanics, like all other branches of scientific discovery, were discovered piecemeal. The process of discovery took place over centuries. There were many investigators, some more prominent than others. The thing I find interesting is the fact that the significance of the piecemeal discoveries were not always understood at the time. That is particularly true of momentum, which was discovered almost like the palaeontologist scratching dirt away from a fossil, a bit at at time. However, Sir Isaac Newton is given credit for creating the branch of physical science we call Mechanics.

All those discoveries makes the Cubli possible, but we had to wait for computers to be invented to make it work. What, may you ask, is a Cubli? Good question. The name “Cubli” is derived from the English word “cube” and the Swiss German diminutive “li.”  The Cubli is a cube 15cm on each side. It contains three reaction wheels that act as the force generators. Their spin is controlled precisely by the computer. It is a mistake to think the Cubli works by gyroscopic force. It doesn’t. The wheels are spun, then suddenly stopped. That creates the reaction force needed to make the Cubli do what it does.

Take a look over the jump to see the Cubli in action.

If you can watch this without smiling, you are a stronger person than I.

For those interested in the science and math behind the Cubli, here is the published paper on it.

Here is more information with less math. This link goes to the web page of the Institute for Dynamic Systems and Control in Zurich, Switzerland.

17 thoughts on “The Cubli; Laws of Motion and Angular Momentum at Play

  1. Nice.

    I love science.

    Chuck, I once knew an engineer who told me “If you ever want to see a bunch of engineers in a meeting freak out? Just walk in and say ‘What about the angular momentum problem?’ and walk out.”

  2. My math is as good as my Farsi but I like this Chuck. I just read that Newton may have suffered from Asperger’s disease. If so, his accomplishments during that fateful summer of 1665 when he invented both calculus and the science of optics is even more remarkable.

  3. Mark,
    Speaking of Asperger’s, it can be both a curse and blessing. Gene has met my grandson. He is now in his junior year of college, and is convinced he has Asperger’s. He does not have the best social skills in the world, but graduated from high school with a 4.2 GPA. Has never made a B in school going all the way back to first grade. He had a challenge in physics for the first time last year and was a nervous wreck thinking he might make his first B. He is a video gamer, and wanted to learn how to program and tweak games in the original Japanese. So in high school, he taught himself Japanese. And can write computer code in Japanese. Gene had him doing tongue twisters in Japanese…it was funny to watch, but also a bit spooky. Talking to him is like talking to Watson the computer on Jeopardy. Asperger’s is a strange condition.

    On second thought, never, ever, play Trivial Pursuit with his dad (my oldest son) for money.

  4. Speaking of inertial systems, Canon has come up with a brushless gimbal system for their EOS cameras. It has to be seen in demonstration to be believed. I use an EOS Rebel, and I want one.

  5. Gene H. 1, December 29, 2013 at 9:59 pm

    Nice.

    I love science.

    Chuck, I once knew an engineer who told me “If you ever want to see a bunch of engineers in a meeting freak out? Just walk in and say ‘What about the angular momentum problem?’ and walk out.”
    ============================
    That works for Big Bang cosmologists too Gene.

    Especially in the context of : “the history of the discovery of the laws of angular momentum and inertia” – OS

    Which came first the law or what the law governs?

    Ok, I will settle for what came second. ;)

  6. Cubli, the world will never be the same once the latest models of breast implants come with it as standard equipment. :)

    Yes, my son says my humor is terrible, but some times it gets a laugh.

    The question I’m asking is where we going to use this cool tech at?

    Some sort of high speed stabilizer, trains, planes autos?

  7. ** Oky1 1, December 26, 2013 at 2:08 pm

    OS,

    I have no doubt that all of the nuke planets in the US/world should be decommissioned & torn down right away. That’s the same opinion of many experts in energy field as well.

    I’m interested if you have asked you theoretical physicist friend what we are going to replace the US’s approximately 20% nuke produced electric with?

    It’s been awhile since I focused heavily on energy issues, but I believe the correct number is about a 1/3rd of Nuke energy is wasted in just getting the fuel out of the ground & refined for the plant.

    (Not accounting for all the wasted energy storing/managing the fuel’s life is used up. 25,000 years?)

    So that lost energy could be available for direct conversion of electric production, we’d then only be talking about a lose of 14% generation if nuke plants were shut down.

    I’m still promoting onsite generation & storage.
    **

    http://jonathanturley.org/2013/12/26/u-s-sailors-sued-japanese-company-over-radiation-injuries-following-the-fukushima-disaster/

    US DOE is bad as any bureaucracy, but there is some useful info there, such as proof of concept/projects.

  8. Thank you SO much for this Chuck. When I was with the National Museum of Science & Industry, I read a lot on Newton (and also on Charles Babbage’s Difference Engine, which we duplicated)

    I liked your statement,

    “On second thought, never, ever, play Trivial Pursuit with his dad (my oldest son) for money.”

    Money is a concept which has passed me by, as you know…but a Trivial Pursuit match against your eldest? Mmmm..interesting! Could we sell tickets, do you think??

Comments are closed.