20
LD Platform Peripherals Guide
13732-000 Rev J
2.4 Environment
Both referenced standards state, sensing in the reverse direction of motion is not relied on as
part of the AMR's safety system. This is because it is used only by software-based obstacle
detection, the LD's reverse travel is limited to <300 mm/s.
If an LD platform is operated in a manner that exceeds this reverse speed limit, the safety sys-
tem will generate and report a fault signal. In normal, autonomous operation, this condition
triggers motion controllers to execute a controlled stop. However, if motion is disabled (E-Stop
button is pressed) and the brake release is overridden, the safety system cannot stop the LD
platformsince power to the motors has already been cut off. Once the fault condition is
resolved, the safety system will stop reporting safety fault to the motion controllers, and the
normal start-up process will initiate.
If this error is occurring, you may decrease the max speed parameter in question. In the Robot
Physical section and Absolute Movement Maximums sub-section of Robot Configuration, the
parameters AbsoluteMaxTransVel and AbsoluteMaxTransNegVel can be set to control the
maximum velocity of the robot. These parameters cannot be set higher than the forward and
reverse limit of the hardware platform currently being used. Lowering these parameters will
prevent the robot from moving at a speed that would cause an overspeed fault.
Following table displays overspeed fault conditions.
NOTE:
The motion settings such as AbsoluteTransVelMax, that limit maximum
allowable velocities in the robot software (ARAM), have no effect on the safety
system.
Table 2-1. Overspeed Limits for Different LD Models
Model
Forward recom-
mended Speed
(mm/s)
Reverse recom-
mended Speed
(mm/s)
Forward
Limit
(mm/s)
i
Reverse
Limit
(mm/s)
i
LD-60
2050
250
2100
300
LD-90
1525
175
1575
225
LD-
90x
1000
100
1050
150
LD-
105CT
1525
175
1575
225
LD-
130CT
1000
100
1050
150
LD-
250
2050
175
2100
225
i
The forward limits indicate where the safety system will report a fault. These speeds may not
be achievable by the robot under its own power. The max forward speed, should always be set
to the defined maximum (or lower) speed, found in the default configuration shipped with the
robot.
