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ENGINEERING TOMORROW
10.6.1 Calculation of flow set-point using anti-jerk functionality
The anti-jerk algorithm uses relative set-point parameters P3572 and P3573 in [%] and absolute set-point parameters
P3734 and P3576 in [IR] and detects the relative or absolute set-point changes in one loop/cycle (10ms). The algorithm
will chose the parameter (absolute or relative) which has the highest change of set-points for each loop (i.e. 10ms) and a
new ‘
modified flow set-point ’ is calculated. Finally, the low pass filter is applied on the ‘ modified flow set-point’ to
calculate the ‘ filtered flow set-point’.
The low pass filter in the function is configurable by P3582 (default cut-off frequency is 10Hz, i.e. P3582 set to 100).
If the EH-spool is commanded to go from left- to right-side or opposite, when crossing neutral, the ramps will be
canceled and the parameter set will change from “
moving towards neutral position ” to “ moving away from neutral
position ”.
For the relative set-point parameters (P3572 and P3573), the value will change depending on the actual spool position.
For the absolute set-point change parameters (P3574 and P3576), the value will always be a fixed set-point value,
parameters shall be configured accordingly.
Important
An anti-jerk function is normally only used on articulated vehicles, where jerk is very common.
Important
Jerk is a sideways hard movement around the articulated point. This Anti-Jerk functionality will minimize the
unpleasant sideways movement around the articulated point.
As an “on-the-top”-feature, further dampen of STW speed fluctuations can be done. So if the general STW Anti-jerk
setup (P3571 to P3576) does not give the enough dampen/satisfying result, the anti-jerk on-the-top function can be
enabled.