Omron MD-900 User Manual

4-20
Overspeed Protection
The AMR has an independent safety system that uses an internal safety controller to monitor its veloc-
ity. This controller uses redundant monitoring and control methods to ensure that the AMR always op-
erates within safe speed limits for driving straight and rotating. Overspeed limits are not adjustable and
independent of parameters detailed in 4-27 Motion Limits on page 4-76.
The safe speed limits are provided below.
• Maximum linear speed: 2380 mm/s for MD-650 and 1900 mm/s for MD-900
If the AMR operates outside the specified safe speed limit, the safety controller registers a system
fault and begins a protective stop sequence. This event causes the AMR's motion controllers to exe-
cute a protective stop (Category 1 according to IEC 60204-1, NFPA79). When the protective stop is
triggered, the system commands a controlled stop at the highest deceleration allowed. During the de-
celeration process, the safety controller continuously monitors the deceleration. If the AMR is not able
to stop quickly enough, the safety controller disables the drive motors and engages the mechanical
motor brakes in order to stop the AMR. Refer to 2-4-16 Safety Function Performance Levels on page
2-20 for more information.
The motor brakes are powerful enough to stop a fully loaded AMR traveling at its top speed. However,
engaging the mechanical motor brakes to stop the AMR is not a typical function. In the unlikely event
that this occurs, you receive an error message in MobilePlanner and on the Operator Panel which
should not be ignored. This error can occur if one of the following conditions is present.
• The AMR software fails to command a controlled stop for any reason.
• The floor is excessively slippery and does not provide good traction.
• The AMR is traveling down a slope steeper than its specified capability.
If this fault occurs frequently, the operating conditions leading up to this event should be investigated.
Contact your OMRON representative for support. If the problem is not resolved, the AMR may stop
operating in order to prevent the use of the potentially degraded brakes. Generally, the degradation of
the motor brakes requires hundreds of these occurrences.
The use of the mechanical motor brakes to stop the AMR too many times will reduce the effectiveness
of the motor brakes. This increases the distance required for the AMR to come to a full stop.
If motion is already disabled (for example, an E-STOP button is pressed) and you release the brakes
manually, the safety system cannot stop the AMR. This is because power to the drive motors is al-
ready disabled.
After you resolve the overspeed condition, the safety system stops registering the safety fault. The
safety system allows for the normal start-up process to begin, but it does not automatically restart the
AMR's operations.
Additional Information
Motion control configuration parameters (such as AbsoluteMaxTransVel parameter) limit the
maximum allowable velocities. Use MobilePlanner to modify the value of these parameters. Re-
fer to the Fleet Operations Workspace Core User's Manual (Cat. No. I635) for more information.
4 Operation
4-40
AMR (Autonomous Mobile Robot) MD-series Platform User's Manual (I681)

Omron MD-900 Specifications

General

Brand	Omron
Model	MD-900
Category	Robotics
Language	English