Probing Lines - HEIDENHAIN QUADRA-CHEK ND 1400 Operating Instructions Manual

51
Measuring Features

Probing lines

A minimum of two points are required to measure a line. There is
no practical limit to the number of points that can be probed, and in
general accuracy is increased by probing more points.
When only two points are probed, Measure Magic will correctly rec-
ognize a line and assign the correct feature. However, when more
than two points are probed, it is possible that the wrong feature type
will be assigned. If the wrong feature type is assigned, it can easily be
In this example, three points are
changed by selecting the correct feature from a menu of alternatives
probed to measure a line
in the DRO screen.
Touch the feature Fit menu... to display the menu of alternative Probed points are shown in the
types View window
A best fit algorithm is used to define lines when more than two points are probed. The line fit to the probed
data can also be changed by selecting the desired fitting algorithm from the Fit menu in the DRO screen.
Please refer to Chapter 12: Reference Materials for details regarding the fitting algorithms.
Measurement results are shown in the Feature list, View screen and DRO screen. The feature graphic in
the View screen shows the feature and the points used to define it. Errors are shown as whiskers connect-
ing the probed points to the feature. The maximum errors are shown in red and are used in the calculation
of form. The DRO screen shows the feature type, feature position, angular orientation of the line, form
error, number of points used, reference frame and the projection plane. When only two points are probed,
the form error is zero. When more than two points are probed, the form error is the sum of the two greatest
opposing error magnitudes.