Nutation (Physik)
Die Nutation ist die Bewegung der Figurenachse eines kräftefreien Kreisels, wenn der Drehimpuls nicht parallel zu einer der Hauptachsen des Kreisels ausgerichtet ist.
Bei einem symmetrischen Kreisel überstreicht durch die Nutation die Figurenachse einen Kegel mit dem Drehimpuls als Achse. Aufgrund der Drehimpulserhaltung bleibt der Drehimpuls dabei in Betrag und Richtung konstant.
Provozieren kann man die Nutation durch Anstoßen eines stabil um seine Figurenachse rotierenden Kreisels.
Nutation
Nutation (nūtātiō) is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behaviour of a mechanism. In an appropriate reference frame it can be defined as a change in the second Euler angle. If it is not caused by forces external to the body, it is called free nutation or Euler nutation (after Leonhard Euler).[1]
A pure nutation is a movement of a rotational axis such that the first Euler angle (or precession) is constant. Astronomers usually make a distinction between precession, which is a steady long-term change in the axis of rotation, and nutation, which is the combined effect of similar shorter-term variations.[2] Therefore it can be seen that the circular red arrow in the planetary nutation diagram indicates the combined effects of precession and nutation, while nutation in the absence of precession would only change the tilt from vertical (second Euler angle). However, in spacecraft dynamics, precession (a change in the first Euler angle) is sometimes referred to as nutation.[3]
- ↑ Lowrie, William (2007). Fundamentals of Geophysics (2nd ed.). Cambridge [u.a.]: Cambridge University Press. pp. 58–59. ISBN 9780521675963.
- ↑ https://wiki.aewi.de/mediawiki/index.php?title=Kategorie:Vorlage&action=edit Seidelmann, P. Kenneth, ed. (1992). Explanatory Supplement to the Astronomical Almanac. University Science Books. pp. 99–120. ISBN 0-935702-68-7.
- ↑ Kasdin, N. Jeremy; Paley, Derek A. (2010). Engineering dynamics : a comprehensive introduction. Princeton, N.J.: Princeton University Press. pp. 526–527. ISBN 9780691135373.