NPM PPCI7443, User Manual

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Operation Theorem
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4.6 Change position or speed on the fly
The PPCI7443 provides powerful position or speed changing function while
axis is moving. Changing speed/position on the fly means that the target
speed/position can be altered after the motion started. Yet, these functions
are not unlimited. Please study carefully all constrains before implement on-
the-fly function.
4.6.1 Change speed on the fly
The change speed on the fly function is applicable on single axis motion
only. Both velocity mode motion and position mode motion is applicable.
The graph above shows the basic operating theory.
The following functions are related to change speed on the fly function.
_7443_v_change() – change the MaxVel on the fly
_7443_cmp_v_change() –change velocity when general comparator comes into
existence
_7443_sd_stop() – slow down to stop
_7443_emg_stop() – immediately stop
_7443
_fix_speed_range() – define the speed range
_7443 _unfix_speed_range() – release the speed range constrain
All the first 4 functions can do the speed changing during single axis motion.
However, the _7443_sd_stop() and _7443_emg_stop() only change the
axis speed to “0”. The _7443
_fix_speed_range() is necessary before any
_7443_v_change() function, and _7443 _unfix_speed_range() release the
speed range constrained by _7443 _fix_speed_range().
_7443_v_change(axis, new_vel, Tacc)
The same Acc/Dec slope
Tacc
new_vel
Time
Speed