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Sebastien
Posts: 219 Handy
Repeatability of the UR after restart of the robot |
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/ Most recent by Grady_Turner
in Programming
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7 comments |
in Programming
Hi pros,
one quick question, I saw a video showing the repeatability of the UR robot:
https://www.youtube.com/watch?v=9orN_aUDY7w
Listed in the specifications of the UR robot is a repeatability of 0.1mm. A question that we have been asked is that the video above shows that the robot is within the specs given. What if you turn off and then on the robot and try to run the same program. Would you still be within the limits or will the robot initialisation steps make this deviate a bit more?
one quick question, I saw a video showing the repeatability of the UR robot:

Listed in the specifications of the UR robot is a repeatability of 0.1mm. A question that we have been asked is that the video above shows that the robot is within the specs given. What if you turn off and then on the robot and try to run the same program. Would you still be within the limits or will the robot initialisation steps make this deviate a bit more?
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@Ryan_Weaver any interest in doing that from the Axis folks?
I think that is proven by many customers running tasks with tight tolerance who turn off their machine every night, yet the robot hits the points it needs to when they power it up in the morning.
Ryan Weaver | Automation Engineer | Axis New England
[email protected]
https://www.youtube.com/user/AxisNewEngland
https://twitter.com/axis_newengland
I guess @Stefan_Stubgaard could explain us why repeatability doesn't drift with reboot or joint firmware update. Stefan?
[email protected]
@Ryan_Weaver explains it beautifully. As the system has true absolute encoders* it will remember it's position after reboot. Joint firmware doesn't affect the positioning.
* True absolute encoders = no battery backup needed
Conventional absolute encoders requires battery to maintain position information in the memory, so a Universal Robot is never affected by loss of position due to dead batteries.
The only time we have seen a loss of repeatability was when the robot crashed at full speed into the machine structure. The base joint mechanically shifted in it's locking key mount, we had to re calibrate to get the program positions back