Trio Motion Coordinator Euro 205, Техническое справочное руководство

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8-170 Trio BASIC Commands
Axis Parameters
Trio Motion Technology
OFFPOS
Type:
Axis Parameter
Description: The
OFFPOS
parameter allows the axis position to be offset by any value without
affecting motion.
OFFPOS
can therefore be used to effectively datum a system at
full speed.Values loaded into the
OFFPOS
axis parameter are reset to 0 by the sys-
tem software as the axis position is changed.
Example: Define the current demand position as zero:
OFFPOS=-DPOS
WAIT UNTIL OFFPOS=0' wait until applied
This is equivalent to
DEFPOS(0)
Example 2: A conveyor is used to transport boxes onto
which labels must be applied.
Using the
REGIST()
function, we can cap-
ture the position at which the leading edge
of the box is seen, then by using
OFFPOS
we can adjust the measured position of
the axis to be zero at that point. There-
fore, after the registration event has
occurred, the measured position (seen in
MPOS
) will actually reflect the absolute dis-
tance from the start of the box, the mech-
anism which applies the label can take advantage of the absolute position start
mode of the
MOVELINK
or
CAMBOX
commands to apply the label.
BASE(conv)
REGIST(3)
WAIT UNTIL MARK
OFFPOS = -REG_POS ‘ Leading edge of box is now zero
Note: The
OFFPOS
adjustment is executed on the next servo period. Several Trio BASIC
instructions may occur prior to the next servo period. Care must be taken to ensure
these instructions do not assume the position shift has occurred.