  The nonlinear dynamics of a cylindrical pinion that is kept at a distance
from a vibrating rack is studied, and it is shown that the lateral Casimir
force between the two corrugated surfaces can be rectified. The effects of
friction and external load are taken into account and it is shown that the
pinion can do work against loads of up to a critical value, which is set by the
amplitude of the lateral Casimir force. We present a phase diagram for the
rectified motion that could help its experimental investigations, as the system
exhibits a chaotic behavior in a large part of the parameter space.
