Examples and tips
PROGRAMMING MANUAL
277
Revi
si
on 3.0
fig. 47
The next step is to analyze the CAM table, to see which values
were used for demanding the position of the slave axis. To do that,
we change the oscilloscope configuration to show a block of values
from Table(0) to Table(999) in red, because these Table memory
entries are where the CAM table is created (see the part of the
program that creates the CAM table above). The changed
configuration is shown in the figure.
fig. 48
The result is given in the figure. The red graph clearly shows a
discontinuity in the position values that the slave axis must follow.
Because the speed is a derivative of the position, at the point of
discontinuity of the position curve the speed gets a high value.
(This value equals infinity in theory, in practice the value is just very
big). This causes the error. The red graph shows where the root of
the problem is. The amplitude of the cosine curve, and therefore
the
end_pos
parameter, has been changed during the execution of
the
CAMBOX
command. The solution is simple: A change of the
end_pos
parameter during
CAMBOX
execution must be
prevented. To do this, either modify the programs in Trajexia, or in
some other controller (if the parameter is changed outside of the
scope of the application programs, for example by a FINS
message).
I52E-EN-03.book Seite 277 Freitag, 29. Juni 2007 11:55 11
