Moving Average; Recursive Average - MICRO-EPSILON optoCONTROL 2700 Operating Instructions Manual

6.4.3.2

Moving Average

Moving Average
M
The arithmetic average
N . Each new measured value is added, and the first (oldest) value is removed from the averaging (from
able filter width
the window).
N
MW (k)
k=1
M =
mov N
This produces short settling times in case of measurement jumps.
Example: N = 4
... 0, 1, 2, 2, 1, 3
2, 2, 1, 3
= M (n)
4 mov
Note In the case of the moving average, only powers of 2 are permitted for the averaging value
est averaging value is 512.
Fig. 6.12: Moving average, N = 8
6.4.3.3

Recursive average

Recursive average
Each new measured value
Formula:
MW + (N-1) x
M (n) =
(n)
rec N
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 behavior.
optoCONTROL 2700
is calculated and output for a series of consecutive measured values according to the select­
mov
MW = measured value
N = averaging value
k = continuous index (in the window)
M
mov
... 1, 2, 2, 1, 3, 4
2, 1, 3, 4
= M
4 mov
Application tips
Smoothing of measured values
●
In contrast to recursive averaging, the effect can be finely controlled.
●
With uniform noise of the measured values without spikes
●
In the case of a slightly rough surface whose roughness is to be eliminated.
●
Also suitable for measured value jumps with relatively short settling times
●
MW (n) is weighted and added to (n-1) times the previous average value.
N = averaging value, N = 1 ... 32768
M
rek (n-1)
n = Measured value index
MW = measured value
M
rec
= average value or output value
Measured values
(n+1) Output value
= average value or output value
Advanced Settings
N . The high­
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