In position, Synchronizing axes – Rockwell Automation 1771-QC , D17716.5.25 SER/B SERVO POS User Manual

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Positioning with Allen-Bradley PC

Chapter 4

4Ć8

Figure 4.8

Moveset Profile for Constant Velocity Moves

Position

Rate +

0

12009

For a continuous move with the next move in the same direction, the
move is complete when the axis feed is done. The 1771-ES expander
immediately begins the feedrate for the next move without waiting for the
following error to close.

For any halt move, single-step move, or a continuous move with the next
move in the opposite direction, the move is not complete until the axis is
in position. The axis is in position when the following conditions are met:

the axis feed is done
following error has closed to within the in-position band

You establish the in-position band in the parameter block. The in-position
band is the largest distance from the endpoint at which you will allow the
axis to be considered in position.

In many applications it is important to synchronize the motion of two or
more axes. In the following sections, we will tell you how to do this.

Halt Moves

For halt moves, axis synchronization is straightforward. When an axis is
in position after a move, the next axis move will not begin until you send
a start command.

In Position

Synchronizing Axes

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