Omron NJ501-1300, Руководство пользователя

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9 Motion Control Functions
9-32
NJ-series CPU Unit Motion Control User’s Manual (W507)
You can read Axis Variables in the user program to monitor jerk.
If you want to specify a rotation direction, such as shortest way, using an index table, set the Count
Mode to Rotary Mode. Next, set the operation direction with the
Direction input variable to the motion
control instruction for an absolute position. You can specify any target position that is within one ring
counter cycle and that is within the upper and lower limits of the ring counter. The
Direction input vari-
able will be ignored when the Count Mode is set to Linear Mode. Positioning will be performed to the
target position.
The following table lists the different directions you can specify in the MC Function Module.
The following example illustrates when positioning is performed towards a target position of
−
20 when
the command current position is 50.
Additional Information
Moves in the same direction as the Current Direction specification if the travel distance is the
same in the positive and negative directions.
Monitoring Jerk
Variable name Data type Meaning Function
_MC_AX[0-63].Cmd.Jerk LREAL Command Current
Jerk This is the current value of the com-
mand jerk.
9-5-5 Specifying the Operation Direction
Direction Operation
Shortest way Motion starts in the direction where the command current position and the target posi-
tion are closer to each other.
Positive direction Motion starts in the positive direction.
Negative direction Motion starts in the negative direction.
Current direction Motion starts in the same direction as the previous operation.
No direction specified Motion starts in the direction that does not pass through the upper and lower limits of
the ring counter. With this direction specification, you can specify a target position that
exceeds the upper or lower limits of the ring counter. If that occurs, relative positioning
is performed using the difference between the target position and the command current
position as the target distance. This enables you to perform multi-turn positioning on
the ring counter.
Example for Shortest Way
0
Target position:
−
20
Moves in negative direction.
Target position:
−
20
Command current position:
50
Modulo minimum
position setting
value:
−
70
Modulo maximum
position setting
value: 100