  We model the dynamical behavior of a three dimensional (3-D) dissipative
oscillator consisting of a $m$-block whose vertical fall occurs against a
spring and which can also slide horizontally on a rigid truss rotating at a
known angular speed law $\omega(t)$. The $z$-vertical time law is obvious,
whilst its $x$-motion along the horizontal arm is ruled by a linear
differential equation to be solved through the Hermite functions and the
Confluent Hypergeometric Function (CHF) $_{1}F_{1}$ (Kummer). After the
rotation time law $\theta(t)$ has been computed, we know completely the mass
motion in a cylindrical coordinate reference: some transients have then been
discussed. Finally, further effects as an inclined slide and a contact dry
friction have been added to the problem, so that the motion differential
equation becomes inhomogeneous and we resort to Lagrange method of variation of
constants, helped by a Fourier-Bessel expansion, in order to manage the
relevant intractable integrations.
