IAI PSEL, Operation Manual

Page: 1038 / 1062

[28] Conveyer
Tracking Related Commands
544
Caution
1) TRMD and TRAC Commands are available only when they are in the same program (task).
2) Execute the Tracking Operation ON Command on the position where there is no interference
to the surroundings with the tracking operation, movement to the point above the datum point
in the working range after the tracking, or the combination of both operations.
3) Ensure to use MOVL Command for the movement on the axis during the conveyor tracking
operation. If the position data (Datum point position information in Work) is “obtained in
normal condition”, perform a positioning quickly with “MOVL” to the point around the position
(around the point above the datum point in the work) considering “the target values for the
axes that the data is not obtained for, such as Z-axis (height)”. The obtained position data is
effective only in “the tracking operation that time” and becomes ineffective after “the tracking
operation that time” is complete.
For SCARA Robot, the robot arm getting close to the area around the peculiar point as the
result of conveyor tracking may cause an abnormal acceleration and it is very risky. In the
case this abnormal acceleration around the peculiar point is occurred, the arm deceleration
angle after the error detection also becomes larger. Do not locate interfering object in the
surroundings. The following errors will be detected if the abnormal acceleration around the
peculiar point:
y
Error No. B74 CP Operation Limited Area Invasion Error
y
Error No. B91 Main Excess Speed Necessity Error
y
Error No. D09 Driver Excess Speed Error
To avoid this phenomenon, the work tracking limit can be set in “All-Axes No.75 Tracking
Operation Complete Work Position”, however, since it all depends on the work position,
there is still a risk that the robot arm reaches the peculiar position unless it is quickly moved
to the position (Datum Point in Work) obtained in normal condition by Tracking Operation ON
Command.
y
It is also an effective way for the debug test operation when turning the system on to
detect in the simple interference check zone before invasion to the peculiar point on the
exist side if the operation is under a comparatively low conveyor speed.
y
If reaching to the axis soft limit or interference range due to the positional correlation of
“minimum work position for tracking operation start” and “point above datum point for
work”, have an appropriate treatment on the sequence to avoid it such as by setting the
different start time for the positioning to the point above the work datum point with a
timer, etc.
4) Since the right for the servo use is occupied by the TRAC Command execution task during
Tracking Operation ON Command, the tracking related servo axis cannot be used from other
tasks. (For SCARA Robot, 4 axes are occupied for the purposes of the posture control and
other related.)
5) For SCARA Robot, it is operated on the work coordinate system of when the conveyor
tracking operation is started during the conveyor tracking operation.
6) Conveyor tracking operation does not stop at the break points of SEL program.
y
The break point only pauses the next program step execution.
7) PUSH Command cannot be used during the conveyor tracking operation.