Measurement Averaging - MICRO-EPSILON confocalDT IFD2410 Series Operating Instructions Manual

Set Sensor Parameters, Web Interface
6.3.3

Measurement Averaging

Measurement averaging is performed after measured values have been calculated, and before they are issued or pro-
cessed through the relevant interfaces.
Measurement averaging
- improves the resolution,
- allows masking individual interference points, and
- "smoothes" the reading.
i
Linearity is not affected by averaging. Averaging has no effect on measuring rate and output rate.
The internal average value is re-calculated for each measuring cycle.
i
The defined type of average value and the number of values must be saved in the controller to ensure they are
maintained after it has been switched off.
The controller is delivered with "moving average, averaging value = 16" as factory settings, i.e. averaging is not enabled
by default.
Moving Average
The definable number N for successive measurements (window width) is used to calculate the arithmetic average M
according to the following formula:
N
MV (k)
k=1
M =
mov
N
Each new measured value is added, and the first (oldest) value is removed from the averaging (from the window). 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
i
Moving average in the controller allows only potentials of 2 for N. The highest averaging value is 1024.
Signal without averaging
Signal with averaging
Fig. 56 Moving average, N = 8
confocalDT IFD2410/2411/2415
MV = measured value,
N = averaging value,
k = continuous index (in the window)
M = average value or output value
mov
... 1, 2, 2, 1, 3, 4
2, 1, 3, 4
= M (n+1)
4 mov
Application tips
- Smoothing of measured values
- The effect can be finely controlled in com-
parison with the recursive averaging
- With uniform noise of the measured values
without spikes
- In case of a slightly rough surface, in which
the roughness should be eliminated
- Also suitable for measured value jumps
with relatively short settling times
Measured values
Output value
mov
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