  We study the motion of classical particles confined in a two-dimensional
"nuclear" billiard whose walls undergo periodic shape oscillations according to
a fixed multipolarity. The presence of a coupling term in the single particle
Hamiltonian between the particle motion and the collective coordinate generates
a fully selfconsistent dynamics. We consider in particular monopole
oscillations and demonstrate that self-consistency is essential in order to
induce chaotic single-particle motion. We also discuss the dissipative
behaviour of the wall motion and its relation with the order-to-chaos
transition in the dynamics of the microscopic degrees of freedom. Analogous
considerations can be extended to higher multipolarities.
