We study the motion of classical particles confined in a two-dimension
al ''nuclear'' billiard whose walls undergo periodic shape oscillation
s 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 self-consistent dynamics. We
consider in particular monopole oscillations and demonstrate that self
-consistency is essential in order to induce chaotic single-particle m
otion. We also discuss the dissipative behavior of the wall motion and
its relation with the order-to-chaos transition in the dynamics of th
e microscopic degrees of freedom. Analogous considerations can be exte
nded to higher multipolarities.