The Polhode Rolls without Slipping on the Herpolhode
Lying in the Invariable Plane
The motion of a rigid body upon which no external forces (or
torques) act is a standard problem in
intermediate classical mechanics.
I have developed a
an object with three unequal principal moments of inertia, and shows the
body, its inertia ellipsoid, the polhode and the herpolhode and the invariable
of the physics and an
of one example are
also available. You can also see the
herpolhode and a projection of the
polhode. This example
is for a body started rotating
very close to the intermediate principal axis
This project was begun at the "Revitalizing the Engineering, Mathematics
and Science Curricula via Symbolic Algebra" NSF workshop held at
Rose-Hulman Institute of Technology in July 1995.
A number of people
there were extremely helpful in getting me through the Maple intricacies,
including Blair Madore, Bill Farr, Brian Evans, but
in particular I want to thank Doug Meade. I also want to thank the organizers
of the workshop, Robert J. Lopez and Mark A. Yoder.
Written by Joel A. Shapiro, 1995
This page and the links concerned with rigid body motion may
be freely copied and distributed, as long as this notice is included.
Joel Shapiro (email@example.com)