Stopping Times Of The Safety System; Limiting Safety-Related Functions - Universal Robots UR3/CB3 User Manual

Limiting Safety
Function
Joint position
Joint speed
TCP position
TCP speed
TCP force
Momentum
Power

2.2 Stopping times of the Safety System

The stopping time of the safety system is the time from a fault or violation of a safety-
related function occurs to the robot is brought to a complete stop and the mechanical
brakes are engaged.
The maximum stopping times in the table must be considered if the safety of the ap-
plication relies upon the stopping time of the robot. E.g. if a fault in the robot results
in a stop of a complete factory line, where certain actions must take place immediately
after the stop, the maximum stopping times must be considered.
The measurements are conducted with the following configuration of the robot:
The worst case stopping time for Stop Category
limits or interfaces can be seen in the following table.

2.3 Limiting Safety-related Functions

Advanced path control software decreases speed or issues a program execution stop
if the robot arm approaches a safety-related limit. Violations of limits will hence only
occur in exceptional cases. Nevertheless, if a limit is violated, the safety system issues
a Stop Category 0.
1
Stop Categories are according to IEC 60204-1, see Glossary for more details.
UR3/CB3
Description
Min. and max. angular joint position
Max. angular joint speed
Planes in Cartesian space limiting robot TCP position
Max. speed of the robot TCP
Max. pushing force of the robot TCP
Max. momentum of the robot arm
Max. applied robot arm power
• Extension: 100% (the robot arm is fully extended horizontally).
• Speed: The TCP speed limit of the safety system is set to the described limit.
• Payload: maximum payload handled by the robot attached to the TCP (3 kg).
TCP Speed Limit
1.0
1.5
2.3 Limiting Safety-related Functions
1
0 in case of a violation of the safety
Maximum Stopping Time
m / 400 ms
s
m / 450 ms
s
I-14 Version 3.3.3