Fitting Algorithm - HEIDENHAIN QUADRA-CHEK 3000 Operating Instructions Manual

11
11.2.1

Fitting algorithm

Short description
If the number of points captured during the measurement of a feature exceeds the
mathematical minimum number of points, there are more points than necessary
for determining the geometry. The geometry is thus overdetermined. Therefore,
fitting algorithms are used to calculate the appropriate substitute feature.
The following fitting algorithms are available:
Gaussian
Minimum zone
Max. inscribed
Min. circumscribed
The fitting algorithms are described below, using a circle as an example:
248
Gaussian
Fitting algorithm that calculates a substitute feature that is
optimally centered between all measuring points.
The statistical mean of all captured measuring points is
used for the calculation. All measuring points are weighted
equally.
Gaussian is the default setting.
Minimum zone
Fitting algorithm that calculates a geometry from two refer-
ence circles. One circle lies on the two outermost measur-
ing points. The other circle lies on the two innermost
measuring points. The two circles have the same center.
The substitute feature is located halfway between the two
circles.
The algorithm is suitable for measuring form error.
Max. inscribed
Fitting algorithm that calculates a substitute feature that is
located within all measuring points and, at the same time,
is as large as possible.
The algorithm is suitable e.g. for measuring holes when
checking mating sizes.
Min. circumscribed
Fitting algorithm that calculates a substitute feature that
is located outside the measuring points and, at the same
time, is as small as possible.
The algorithm is suitable e.g. for measuring pins or shafts
when checking mating sizes.
The center of the minimum circumscribed circle does not coincide with
the center of the maximum inscribed circle.
Measurement evaluation | Evaluating a measurement
HEIDENHAIN | QUADRA-CHEK 3000 | Operating Instructions | 6/2016