Omron SCARA YRCX Series, Руководство по программированию, Страница: 330 / 506

9-2 Chapter 9 PATH Statements
8
9
10
11
12
13
4
Cautions when using this function
■
Paths may comprise no more than 1000 points (total) linear and circular segments. 1 point forms 1
linear segment by PATH L command and 2 points form 1 circular segment by PATH C command.
Number of points specified by PATH L 1000
２
Number of points specified by PATH C
+
≦
■
The robot must be positioned at the path start point when PATH motion is executed (by PATH
START statement).
■
At points where circular and linear segments connect, the motion direction of the two connecting
segments should be a close match (as close as possible). An excessive difference in their motion
directions could cause vibration and robot errors.
Circular and linear segment connection point:
if there is a large difference between the motion directions of the connecting segments
Good example Poor example
■
Where a linear segment connects to another linear segment, the motion path passes to the inner
side of the connection point. Moreover, as shown in fig. (1) below, the faster the speed, the
further to the inner side the path becomes. To prevent significant speed-related path shifts, add
more points as shown in fig. (2). Note also, that in some cases, the speed may have to be reduced
in order to prevent errors from occurring.
Linear segments connection point: Prevents a deviation
(1) (2)
Increase the number
of points
High speed
Low speed
■
If an error occurs due the robot's inability to move at the specified speed:
Robot acceleration/deceleration occurs if the speed setting is changed when PATH motion begins,
stops, or at some point along the path. At such times, an error may occur before motion begins if the
distance between points is too short for the specified speed to be reached. In such cases, a slower
speed must be specified. If the error still occurs after the speed is lowered, adjust the PATH points to
increase the length of the linear or circular segments which contain acceleration or deceleration zones.
■
The hand system used during PATH motion must be the same as the hand system used at the
path's start point. The same applies if the path is to pass through points where hand flags are set.
Differing hand systems will cause an error and disable motion.
■
The first arm and second arm rotation information during PATH movement must be the same as
the first arm and second arm rotation information at the PATH movement's START point. If the
two are different, an error will occur and movement will be disabled.
■
If the robot is stopped by a stop signal, etc., during PATH motion, this is interpreted as an execution
termination, and the remaining path motion will not be completed even if a restart is executed.