HEIDENHAIN ND 1400 User Manual

Page 65

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51

6

Measuring

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

changed by selecting the correct feature from a menu of alternatives

in the DRO screen.

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.

Touch the feature Fit menu...

to display the menu of alternative

types

Probed points are shown in the

View window

Measuring Features

In this example, three points are

probed to measure a line

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