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Advanced Settings
confocalDT 24x1
i
Moving average in the controller IFC24x1 allows only potentials of 2 for N. The high-
est averaging value is 1024.
Application tips
-
Smooths measured values
-
The effect can be finely controlled in
comparison with the recursive averaging
-
With uniform noise of the measured val-
ues without spikes
-
At a slightly rough surface, in which the
roughness should be eliminated
-
Also suitable for measured value jumps
at relatively low settling time
Signal without averaging
Signal with averaging
Fig. 39 Moving average, N = 8
Recursive average
Formula:
MV + (N-1) x
(n)
M
rec (n-1)
N
M (n) =
rec
MV = measured value
N = averaging value, N = 1 ... 32768
n = measurement index
M
rec
= average value or output value
The weighted value of each new measured value MV(n) is added to the sum of the previ-
ous average values
M
rec
(n-1).
Recursive averaging allows for very strong smoothing of the measurements, however
it requires long response times for measurement jumps. The recursive average value
shows low-pass behaviour.
Application tips
-
Permits a high degree of smoothing of the
measurement values. However, it requires
extremely long transient recovery times for
measured value jumps (low-pass behav-
iour)
-
Permits a high degree of smoothing for
noise without strong spikes
-
For static measurements, to smooth signal
noise
-
For dynamic measurements on rough
surfaces, to eleminate the roughness, e. g.
roughness of paper
-
For the elimination of structures, e. g. parts
with uniform grooves, knurled rotary parts
or roughly milled parts
-
Unsuitable for highly dynamic measure-
ments
Signal without averaging
Signal with averaging
Fig. 40 Recursive Average, N = 8
Median
A median value is formed from a preselected number of measurements.
When creating a median value for controller IFC24x1, incoming readings are sorted after
each measurement. Then, the average value is provided as the median value.
