Hello everyone,
We just installed a UR10e with an addition of a Safety Scanner (Leuze RSL 400). Everything is working fine (the reduced speed zone and the stop zones). However when we are setting up a new program, or adjusting a current one and manually teaching various waypoints, the scanner is still active. Because of this we are unable to physically move the robot by hand due to the scanner saying that we are in the stop zone. The only way we currently have is to remove the sensor wires from the safety I/O and replace them with the original jumpers. There has got to be a better way. Is there a way to disable or ignore the safety scanner when not in automatic mode? I see that a TPED is able to due this, but I do not believe the scanner is considered a TPED.
New to the Forum and new to robots.
Having been in the exact same situation, here’s what we did. The contacts are just from the scanner, so however you currently have it wired, just wire in parallel another switch. In our case it’s a 2 position key switch. When the switch is thrown to manual, it just puts 24v into the safety inputs. When it’s not, 24V is put into the safety channel when the safety contacts are made (ie the scanner is clear). In this way, you can stand inside the scanner while in teach mode. Just be sure you have at least 2 sets of contacts on whatever switch you use to bypass it so you don’t compromise the dual channel nature of the scanner.
Ideally, UR would implement some sort of “bypass safety” option when holding the freedrive button and the user can just turn this off and on via the teach pendant. You figure if you’re manually trying to move the robot, you know are accepting whatever risk is involved with being close to the robot.
Yep got to wire in a ‘Teach Mode/ Bypass’ switch.
Just be sure to wire another contact (ideally 2 channel) of that switch that ensures the system won’t run in auto in that mode, you really dont want scanner disabled then.
Yes, there is a way. Do not use SI0 and SI1 inputs for safeguard. Instead you have some configurable inputs you can use (within safety) that are called "Automatic mode safeguard stop’'. Using this input your area scanner will only trigger a safeguard stop when robot is in Automatic mode (NOT in manual mode). You can read more about this in the user manual.
What does this use to determine if the robot is in Auto mode? An Input signal? Or something like being in Remote mode?
You need to configure a ‘‘3 position switch’’ to be active first before the Automatic Mode Safeguard Stop inputs become available in the dropdown selections. The 3 Position Switch will allow you to have a switch to change between automatic and manual mode.
We used Banner XS26 safety controllers on the machine tending cells that we used to do as this gave us the ability to have a complex safety cell arrangement with multiple safety scanners, light curtains, etc. One of the things we did was use a safety bypass key in the system. The safety controller would broadcast the status of the key over modbus and the program then read that status and would not allow the program to run unless the key was in the run position or a supervisory code was used to override the system. If you do follow this approach you could also automatically drop the speed slider to a lower value so that while the safety system is bypassed so the program executes at a slower speed. It’s also possible to make a call to the server and understand what mode the system is in (auto/manual) and you could handle the bypass key differently there as well, not allow in auto mode which would require a password to enter manual mode.
With the bypass key, we also set a time that was allowed to be bypassed, while developing the program we would set the bypass time to be several hours. Once the system was ready for the operation we would change the bypass time to 1 minute, after that time no matter what state the key is in the system does not bypass the safety until the key is reset and turned back to teach. This prevented someone from just turning on the key, entering the code, and then letting the system just run with the safety bypassed. This is functionality built into the Banner controller.
The only downside of this is that it requires the programmer to ensure this functionality is in each program. This was an approach we developed prior to UR releasing the 3PE device functionality but it’s still valid and safer than just having a key switch.
Thanks, and thanks to all of the responses. A lot to think about. I am planning on adding a key switch. But you made a good point that I don’t want to stay that way indefinitely.
What we did with ours was took the normally closed contacts of the key switch and wired that in with the inputs to “Reduced Mode” so that whenever the key was engaged, the scanners were bypassed, but the robot was forced into reduced mode. Figured no one is going to leave the scanners bypassed if it means the robot moves at like 10% speed.
that’s a good idea too