Don't forget that the rocket is upright and a car/bike is horizontal. And
it will work if you weigh the vehicle and locate the CG having already
known the CP.
Skip
At 03:15 PM 9/9/02 -0400, Waldron, James wrote:
>From my model rocket days. Won't work for a full size vehicle, but a
>correctly weighted model should suffice. Last line is the kicker.
>
>"There is a relatively simple test that you can use on a model rocket to
>determine the stability. Tie a string around the body tube at the location
>of the center of gravity. Then swing the rocket in a circle around you
>while holding the other end of the string. After a few revolutions, if the
>nose points in the direction of the rotation, the rocket is stable and the
>center of pressure is below the center of gravity. If the rocket wobbles, or
>the tail points in the direction of rotation, the rocket is unstable.
>
>You can increase the stability by lowering the center of pressure (increase
>the fin area) or by raising the center of gravity (add weight to the nose.)"
>
>from http://www.grc.nasa.gov/WWW/K-12/airplane/rktstab.html
>
>Thanks,
>Jim.
|