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XPS-Q8 Controller
XPSDocumentation V1.4.x (EDH0301En1060 — 10/17)
Figure 33: PVT trajectory element in execution: the comparison.
A PVT trajectory must have three parameters: position, velocity and time. With a given
target displacement, output velocity and time duration, the PVT trajectory calculates
intermediate positions and velocities as a function of time.
With an output velocity of 50 mm/s, the positioner has "enough" time to achieve the
displacement within the assigned time (100 ms) in the forward direction. The velocity
increases at the beginning and then slows down towards the end. The position always
increases up to the target position (5 mm).
On the other hand, when the output velocity is set to 500 mm/s, the positioner does not
have enough time to achieve the displacement and speed output required in the forward
direction. So the positioner will first reverse the direction of motion to be able to
approach the end position with a speed of 500 mm/s.
8.3.6
Trajectory File Description
The PVT trajectory is described in a file that is in the ..\public\trajectories folder of the
XPS controller. Each line of this file represents one element of the trajectory.
A line contains several data separated by a comma. The number of data in each line
depends on the number of positioners in the MultipleAxes group. The first data in each
line is the duration of the element. The following data is grouped in pairs of two
representing the displacement and the output velocity for each positioner of the group.
So the line format is as follows:
Data #1:
Data #2:
Data #3:
Data #4:
Data #5:
(And so on...)
The first positioner is always the first defined in the system.ini of the MultipleAxes
group (see ActuatorInUse), the second positioner is always defined as second, and
so on...
Element duration (seconds).
1st positioner's displacement (units).
1st positioner's output velocity (units/s).
2nd positioner's displacement (units).
2nd positioner's output velocity (units/s).
NOTE
104
Motion Tutorial
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