Aerotech UNIDEX 600 Series, Руководство пользователя

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U600 User’s Guide Introduction and Overview
Version 1.4
Aerotech, Inc
. 1-7
finishes before a following command occurs which requires the first move to be complete.
For example, a slow carriage move might need to be completed before a part loader can
approach the axis or a collision occurs.
Cam Table (or master-slave) motion allows the programmer to direct that a particular
axes position be dependent on another axes position or velocity. The programmer
downloads a set of values into the axis processor (960) that dictate the required position
or velocity of a slave axis, given another axes’ (the master’s) position. When in-between
the dictated master positions, the controller interpolates linearly or by cubic spline to
obtain the correct slave value for that master axis position. This type of movement is the
most flexible, allowing the programmer to completely dictate any position or speed
profile to the motion. The programmer can also achieve multi-axis synchronized
movement by slaving multiple axes to the same master. Finally, this type of motion can be
used to dictate motion based on analog input signals. See the AerCamTablexxx library
functions for more details on camming motion.
1.5.3. Monitoring Motion
The user can monitor all sorts of axis processor status, including what stage the movement
is in. Please see the Status1, Status2, Status3, and Mode1 Task parameters in Appendix C
for details on availability. The CNC interface allows the programmer to specify code to
be executed when certain conditions occur. Also, see Chapter 2 section on Faults for more
monitoring capabilities.
1.5.4. Multi-Axis Motion
In any of the three motion types, the user can direct that multiple axes be moved
simultaneously. However, there are two types of simultaneous motion: contoured, and
non-contoured. In both types the involved axes begin movement at the same time. In
contoured movement the speed of the axes is coordinated so that all the axes complete
their movement at the same time. Contoured movement follows specific controlled paths
through the space defined by the axis through which it moves. In non-contoured moves,
each axis follows its own dictated speeds independently, and may finish their movement
at different times.
All synchronous and asynchronous motion is non-contoured, except certain motion
available from the CNC: G1, G2, G3. The term contoured does not apply to cam directed
motion, since the tables determine the intra-axis synchronization.
1.5.5. Motion Resolution
The servo loop normally runs 4 cycles per millisecond, translating velocity and distance
commands into motor torques. Normally, the axis processor generates new velocity and
position commands every millisecond, which rely upon the user-specified profile.
However, in synchronized CNC motion (G1,G2) the points lying on the user-specified
profile are generated every 10 milliseconds and the controller uses cubic splines to
generate 1 millisecond values lying between the user-specified points.