The purpose of this article is to model the dynamics of a top with a f
inite radius tip on a curved basin in a gravitational field without (a
nd with) energy addition and dissipation. This is an extension of a ve
ry general and classical problem and requires development of a method
for treating the dynamical interactions between the two curved surface
s. The full nonlinear equations of motion are indicated; however, thes
e equations are complex and do not show the dominant mechanisms that d
efine the system motions. A novel method of ''partial linearization''
is employed that reduces the equations of motion to a relevant and tra
ctable form in which these mechanisms ave clearly exposed. The model a
nd related results are compared with relevant examples from the litera
ture. The movement of the top is simulated by an integration of the fu
lly nonlinear equations of motion and compared with the partially line
arized results. (C) 1995 John Wiley & Sons, Inc.