Actual pressure/force filter, Actual pressure/force rate filter, Actual pressure/force – Delta RMC151 User Manual
Page 930: Filter, Rate filter, E actual pressure/force filter, E actual pressure/force
RMC70/150 and RMCTools User Manual
The filter frequency range is limited to greater than 0.01 due to inaccuracies in the
calculations for lower values. The filter is disabled (without notice to the user) when the
frequency is set above 1/4 the sample frequency (500Hz for 500us loop, 250Hz for 1ms
loop, 125Hz for 2ms loop, 62.5Hz for 4ms loop).
Why Bother?
•
Filtering makes the plots look cleaner.
•
Filtering can be used to "smooth" a reference input.
•
Filtering the input can reduce noise in the feedback which may improve system control.
9.2.2.2.20.7. Actual Pressure/Force Filter
Type: Axis Parameter Register
RMC70 Address: Primary Input: %MDn.4, where n = 12 + the axis number
Secondary Input: %MDn.22, where n = 12 + the axis number
RMC150 Address: Primary Input: %MDn.4, where n = 24 + the axis number
Secondary Input: %MDn.22, where n = 24 + the axis number
System Tag: Pressure Input: _Axis[n].PrsFilter
Force Input: _Axis[n].FrcFilter
where n is the axis number
How to Find: Axes Parameters Pane, All tab: Feedback → Filtering/Modeling
Data Type: REAL
Units: Hz
Range: 0 (Off) or greater than 0.01
Default Value: 0
Description
This parameter specifies the cut-off frequency of the Actual Pressure/Force input filter in
hertz. The filter is applied to the Actual Pressure/Force before it is used in the control
algorithm. Therefore, changes to this filter value will affect control, and may require
retuning the axis. The filter is a low-pass fourth order Butterworth filter.
Setting this value to zero (0) disables the filter.
Notice that this Actual Pressure/Force filter is independent of the Actual Pressure/Force
Rate Filter. The Actual Pressure/Force Rate Filter does affect control and only affects the
displayed Actual Force Rate.
Limits
The filter is limited to greater than 0.01 due to inaccuracies in the calculations for lower
values. The filter is disabled (without notice to the user) when the frequency is set above
1/4 the sample frequency (500Hz for 500us loop, 250Hz for 1ms loop, 125Hz for 2ms
loop, 62.5Hz for 4ms loop).
Why Bother?
Filtering the pressure/force input can reduce noise in the feedback which may improve
system control. It also makes the plots look cleaner.
9.2.2.2.20.8. Actual Pressure/Force Rate Filter
910
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