  We study the drift of suspended micro-particles in a viscous liquid pumped
back and forth through a periodic lattice of pores (drift ratchet). In order to
explain the particle drift observed in such an experiment, we present an
one-dimensional deterministic model of Stokes' drag. We show that the stability
of oscillations of particle is related to their amplitude. Under appropriate
conditions, particles may drift and two mechanisms of transport are pointed
out. The first one is due to an spatio-temporal synchronization between the
fluid and particle motions. As results the velocity is locked by the ratio of
the space periodicity over the time periodicity. The direction of the transport
may switch by tuning the parameters. Noteworthy, its emergence is related to a
lattice of 2-periodic orbits but not necessary to chaotic dynamics. The second
mechanism is due to an intermittent bifurcation and leads to a slow transport
composed by long time oscillations following by a relative short transport to
the next pore. Both steps repeat in a quasi-periodic manner. The direction of
this last transport is strongly dependent on the pore geometry.
