Kollmorgen AKD PDMM series, User Manual

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AKD PDMM User Guide | 11.2.4.6 Setting up a motion profile motion task
Note that the motion task target velocity is only reached in case of a symmetric table (see chapter 1.2 for
more details). The velocity will be different in case that the customer table is non-symmetric.
11.2.4.6 Setting up a motion profile motion task
It is recommended to set-up any motion task via the AKD Workbench PC software. The S-curve profile
and the 1:1 profile will be selected via a drop-down menu.
It is also possible to select to adjust a motion task on a command line level with the help of the MT.xyz
commands. There are 2 statements which are mentioned within this chapter:
l
A trapezoidal acceleration, a 1:1 customer table motion task or a standard S-curve motion task will be
selected via the bits 10 and 11 of the MT.CNTL command.
l
The MT.TNUM parameter describes for each motion task, which table to use for the 1:1 customer
table motion task or the standard S-curve motion task. The parameter MT.TNUM will be ignored in
case that a trapezoidal motion task has been selected.
For more details please refer to the AKD Parameter and Command Reference documentation in the AKD
Workbench help menu.
11.2.4.7 Drive reaction on impossible motion tasks
For all motion tasks, which use a motion profile table as the shape for the velocity profile, the motion task
properties must be pre-calculated and it must be evaluated in advance, if a motion task can be handled
without any problems or if some of the motion task parameters must be re-calculated automatically by the
AKD.
An impossible motion task occurs when the user has not specified enough movement in order to accel-
erate to the motion task target velocity and to decelerate to velocity 0 without exceeding the distance to
travel.
1:1 customer table motion task
As already described in chapter 2.3, it is not allowed activating a 1:1 profile motion task while another
motion-task is currently running. A 1:1 customer table motion task must start from velocity 0.
When activating a 1:1 customer table motion task the AKD pre-calculates the expected peak-velocity and
check is the velocity exceeds the minimum of the MT.V, VL.LIMITP and VL.LIMITN limitation.
The expected peak-velocity according to the figure above can be calculated via using the following for-
mula:
The ‘distance to travel’ is defined in the motion task settings MT.P & MT.CNTL. In case that VPeak-
Expected exceeds the minimum of the MT.V, VL.LIMITP or VL.LIMITN setting, the AKD re-calculates tto-
tal in a way, that VPeakExpected does not exceed the velocity limitations.
The AKD accelerates and decelerates within the same time in case of a 1:1 profile and therefore different
settings for MT.ACC and MT.DEC are not considered.
11.2.4.8 Standard customer table motion task
Starting from velocity 0 without change-on-the-fly to a following motion task
Similar to the considerations in chapter 4.1 the ‘distance to travel’ of a motion task is specified by the
motion task settings MT.P & MT.CNTL. Furthermore the target velocity of the motion task (MT.V) and the
acceleration and deceleration (MT.ACC and MT.DEC) are part of the motion task settings.
An impossible motion task setting would be, if there is not enough ‘distance to travel’ selected by the user
in order to accelerate to the target velocity via the selected acceleration (internally converted to
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