The Rigid-Body Dynamics of a Spinning Axisymmetric Body Subject to an Impulsive Mass Ejection

Abstract

The rotational motion of bodies is a well-understood branch of dynamics. In this report, we apply those methods to study the problem of a spinning axisymmetric body that, in an instant, impulsively ejects a portion of its mass radially from the residual body. Not only is the residual body no longer axisymmetric, but the process of ejecting mass induces changes to the linear and rotational momentum of the residual body, as well as to its inertial properties. The ejection also produces precessive motion in the residual body. This report solves for the net state of the body in the immediate aftermath of the mass ejection. It then considers both an axisymmetric approximation to the residual motion, if the mass ejection is small, or, for the general case, solves the rotational momentum and energy equations in the body frame of reference, using a novel variation on a geometrical approach. The results of these analyses allow one to determine the range of precessive motion of the residual body.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 31, 2018
Accession Number
AD1062895

Entities

People

  • Steven B. Segletes

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Abstracts
  • Angular Momentum
  • Axisymmetric
  • Coordinate Systems
  • Dynamics
  • Eigenvalues
  • Eigenvectors
  • Ejection
  • Equations
  • Equations Of Motion
  • Geometry
  • Inertia
  • Linear Momentum
  • Mathematics
  • Mechanics
  • Military Research
  • Molecular Mechanics Methods
  • Moment Of Inertia
  • Momentum
  • Orientation (Direction)
  • Precession
  • Rotation
  • Symmetry
  • Three Dimensional

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Aerodynamics/Aeronautics.
  • Approximation Theory.