Single Piezo-Actuator Rotary-Hammering Drill  The minimal number
of parts in this drill increases reliability and eliminates
potential failure points.  This innovation comprises a compact
drill that uses low-axial preload, via vibrations, that
fractures the rock under the bit kerf, and rotates the bit to
remove the powdered cuttings while augmenting the rock fracture
via shear forces. The vibrations “fluidize” the powered cuttings
inside the flutes around the bit, reducing the friction with the
auger surface. These combined actions reduce the consumed power
and the heating of the drilled medium, helping to preserve the
pristine content of the produced samples.  Single Piezo-Actuator
Rotary-Hammering Drill. The bit is interfaced with the horn via
a bit rotating base and is bolted to the horn via a bearing and
preload spring." class="caption" align="right">The drill
consists of an actuator that simultaneously impacts and rotates
the bit by applying force and torque via a single piezoelectric
stack actuator with