HEIDENHAIN TNC 640 (34059x-01) Cycle programming - Manual (Page 518)

518 Touch Probe Cycles: Automatic Kinematics Measurement
1
9
.4 MEA
S
URE KINEMA
TICS (Cy
c
le
451, DIN/ISO: G451; Option)
Notes on the accuracy
The geometrical and positioning errors of the machine influence the
measured values and therefore also the optimization of a rotary axis.
For this reason there will always be a certain amount of error.
If there were no geometrical and positioning errors, any values
measured by the cycle at any point on the machine at a certain time
would be exactly reproducible. The greater the geometrical and
positioning errors are, the greater is the dispersion of measured
results when you perform measurements at different positions.
The dispersion of results recorded by the TNC in the measuring log is
a measure of the machine's static tilting accuracy. However, the
measuring circle radius and the number and position of measuring
points have to be included in the evaluation of accuracy. One
measuring point alone is not enough to calculate dispersion. For only
one point, the result of the calculation is the spatial error of that
measuring point.
If several rotary axes are moved simultaneously, their error values are
combined. In the worst case they are added together.
If your machine is equipped with a controlled spindle, you
should activate the angle tracking in the touch probe table
(TRACK column). This generally increases the accuracy of
measurements with a 3-D touch probe.
If required, deactivate the lock on the rotary axes for the
duration of the calibration. Otherwise it may falsify the
results of measurement. The machine tool manual
provides further information.