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Supplier of UltraHigh Accuracy
Coordinate Measuring Machines and Ultrasonic Scanners! |
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“Stabilis”,
Latin for stability and by literary definition in the physical context,
“…the ability to resist forces that tend to change the form or position of a
body” and by Resource Engineering’s definition “a proprietary
technological advantage that allows us to produce measuring machines to achieve
outstanding accuracy and repeatability of measurement in less than ideal
environmental conditions”. |
The
most detrimental effect of thermal influence on a measuring machine’s
performance is NOT of the first order error or the 'linear growth' associated
with the material based on its Coefficient of Thermal Expansion (CTE). The most
detrimental is the second order error or the bending moments associated with a
guideway or a structure and its ability to NOT grow linear because of local
thermal influence due to gradients across the machine in all directions.
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Stabilis
Technology therefore incorporates advanced materials technology, those materials
possessing a near-zero coefficient of thermal expansion, in producing the
machine’s structures and guideways. The utilization of thermally inert
materials of INVAR36, Ultra-High Modulus (UHM) Carbonfiber and CARBINVAR
throughout the metrology frame reduces the effect of physical changes to the
structures and guideways by an order of magnitude (factor of 10) over that of
traditional materials of carbon steel, cast iron and, by two orders of magnitude
over aluminum. | |
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CARBINVARGuideway
Assemblies are a Patent Pending Technology that combines exotic materials of
High Modulus Carbonfiber with INVAR 36 metal alloy. These materials having
nearly matching Coefficient of Thermal Expansions (CTE’s) are bonded together,
ground and lapped to achieve thermally inert guideway substrates of high
accuracy and extreme dimensional and geometric stability in changing
environments. The CTE’s of these materials are less than 1 ppm/F°. CARBINVAR
Guideway assemblies have no limitation on configuration, cross-section and
length. |
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To further reduce and/or eliminate the potential for bending moments or distortions
in the measuring machine’s structures, Spaceframe construction is exploited.
Spaceframe structures consist of 3-Dimensional triangulated construction of
fully welded assemblies of plates through tab-n-slot construction of
intersecting members and interlocking adjoining members, whereby material that
is not contributing to the overall strength of the structure is removed and that
mass is then redistributed in terms of cross members of lateral and diagonal
supports to significantly stiffen the structure. The material that has been
removed is taken in the form of a triangulated lattice pattern, which is then
left open to dramatically decrease the thermal inertia of the structure and
allow the environment to circulate through the structure’s framework. |
The final compliment to the measuring frame the ULTIMATE in high-resolution position
feedback is obtained from laser interferometry with real-time environmental
compensation. Each axis is fitted with its own laser scale system to provide
1-ppm accuracy and 20-nanometer resolution to optimize the stability and dynamic
positioning capabilities of the measuring system. The 4 axis laser scale system
includes an environmental compensation processor unit with temperature, humidity
and pressure sensors to continually monitor the environment and ‘correct’
the quadrature feedback of the lasers to the motion controller in real-time for
changes to the machines immediate environment. |
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Published by Resource Engineering, Inc.
Copyright © 2000 by [Resource Engineering]. All rights reserved.
Revised: 21 Aug 2000 13:52:17 -0700
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