The accuracy of goniometers and rotary
machine axes equipped with angular encoders
is mainly determined by the runout
error of the mechanical axis, manufacturing errors of the encoder scale and
the eccentricity between axis and encoder.
The absolute calibration of the angular
readings of goniometers and rotary
encoders is often made by the rosette
technique. This procedure is based on
measuring the difference of the angles
between two adjacent facets of a precision
polygon mirror. By measuring all the
facet angle differences a calibration
curve is obtained which can be used to
correct the angular readings of the encoder
for the complete system, whether
machine axis, goniometer or index table.
The calculations involved are quite cumbersome
and complex without software
assistance, but easily done with the dedicated
software Plug-In of the OptiAngle® software. The measurements can be performed
with manual axis rotation or with
motor control if available.
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OptiAngle® Plug-In for index table calibration
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Products > TriAngle® > Application > Calibration of Index Tables
