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Fig.1: NMT 20 module on top of an NMT 50 module

Fig.
2: Two NMT 50 modules as XY-stage

Fig.3:
NMT 10-L module moving a 2 kg weight
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A
new set of motorized tables developed by Klocke Nanotechnik allows high
strokes at small volumes. The modules are driven by the Nanomotor®.
Loads of up to two kg can be moved over centimeters of stroke with down
to 2 nm resolution. Manipulation in many degrees of freedom is possible
without backlash. The modules NMT xx-L are longer, but thin like a pencil.
In most of the NMT-modules position measurement systems can be included
without increasing the size. The resolution of the position sensor is
better than 10 nm. All NMT modules can easily be fixed onto each other.
Very small connectors allow the exchange of a module without removing
cables. The NMT-Zxx are modules for vertical movement. They have an internal
load compensation to lift up loads. Nanomotor-Grippers and force sensors
that can easily be fixed on these modules are available.
Principle of operation (What's
the trick?):
The primary objective during the development of these Nanorobotics modules
was a resolution in movement of a single Nanometer. This is made possible
in principle by the Nanomotor®,
developed by Dr. Klocke and his team in Aachen. Compared with other high
stroke piezo drives the Nanomotor has a real fine positioning stroke of
more than a micron. Within this stroke the Nanomotor behaves exactly like
a piezo, without backlash.
The combination of the Nanomotor with mechanical guiding elements like
ball bearing tables or gears should also eliminate the play of the mechanical
guiding element and lead to a superior movement resolution, free of any
backlash. But it didn't. The movement of a first prototype showed a kind
of backlash with 50 nm amplitude in an Electron Microscope. This value
is much smaller than mechanical play and too big for a piezo drive. The
analysis of the whole mechanical chain in this linear stage with a high
resolution Electron Microscope led to the source of this backlash. The
movement of this small motorized stage caused a compression of materials
used in this setup. Even the elastic constants of materials reduce the
performance of this device. After this result the linear stage was developed
in a new design with other materials and geometries. The backlash caused
by compression could be reduced in our new high resolution stages from
50 nm down to an amplitude of below 1 nm. This is the distance of 5 atoms!
Furthermore, compared with other piezo drives the Nanomotor does not press
in this design against the mechanical guiding elements from the side and
so avoids additional off-axis movements. Only with the precision of the
Nanorobotics modules a coarse approach and a real fine adjustment can
be fulfilled in one system: The fine positioning mode has a range of more
than a micron without making coarse steps - another advantage compared
with other systems. For manipulation tasks in Electron or Ion Microscopes
this achieved precision is essential. These Nanorobotics modules are also
the key elements for the precision of our Micro Production Systems.
Details and applications are described in the Schneeberger
Information Bulletin.
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