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XPS-Q8 Controller
XPSDocumentation V1.4.x (EDH0301En1060 — 10/17)
There are two types of moves that can be commanded: an absolute move and a relative
move. For an absolute move, the positioner will move relative to the HomePreset
position as defined in the stages.ini file. In most cases the HomePreset is 0, which
makes the home position equal to the zero position of the positioner. For a relative
move, the positioner will move relative to the current TargetPosition. In relative moves,
it is possible to make successive moves that are not equal to a multiple of an encoder
step without accumulating errors.
Absolute and relative moves can be commanded to positioners and to motion groups.
When commanding a move to a positioner, only the position parameter for that
positioner must be provided. When commanding a move to a motion group, the
appropriate number of position parameters must be provided with the move command.
For instance for a move command to an XYZ group, 3 position parameters must be
defined.
When commanding a move to a motion group, all positioners of that group will move
synchronously. For any move, the controller will always determine the shortest time
within the positioner's parameters setup. All positioners will start and stop their motion
at the same time. This type of motion is also known as linear interpolation.
The functions for absolute and relative motions are GroupMoveAbsolute() and
GroupMoveRelative() respectively.
Example
A motion system consisting of one XY group called ScanTable and one SingleAxis
group called FocusStage. ScanTable has two positioners, called ScanAxis and StepAxis.
...
GroupHomeSearch (ScanTable)
GroupHomeSearch (FocusStage)
After homing is completed...
GroupPositionCurrentGet (ScanTable, Pos1, Pos2)
... will return 0 to Pos1 and 0 to Pos2, assuming PresetHome = 0.
GroupPositionCurrentGet (FocusStage, Pos3)
Will return 0 to Pos3, assuming HomePreset = 0.
GroupMoveAbsolute (ScanTable, 100, 50)
GroupMoveAbsolute (ScanTable.StepAxis, -20)
The second move is only for one positioner of that group and can be only
executed after the first move is completed. After all moves are completed...
GroupPositionCurrentGet (ScanTable, Pos1, Pos2)
... will return 100 to Pos1 and -20 to Pos2.
GroupMoveRelative (FocusStage, 1)
GroupMoveRelative (FocusStage, 1)
The second move can be only executed after the first move is completed. After
all moves are completed...
GroupPositionCurrentGet (FocusStage, Pos3)
... will return 2 to Pos3.
The velocity, acceleration and jerk time parameters of a move are defined by the
function PositionerSGammaParametersSet() (see also section 7.1). When the controller
receives new values for these parameters during the execution of a move, it will not take
these new values into account on the current move, but only on the following moves. To
change the velocity or acceleration of a positioner during the motion, use the Jogging
mode (see section 7.5).
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Motion Tutorial
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