UR e-series: Allow tool communication without uninstalling URCap?

felixvd 2020-08-07

As discussed in this Github thread, it appears that the Robotiq Grippers URCap is always active and thus blocks the RS-485 port. This seems to make it impossible to control the grippers from the outside, unless the URCap is removed.

Obviously, removing the URCap is undesirable, as it removes the Gripper commands from the teaching pendant. But when controlling the robot remotely, it is equally desirable to have access to the gripper.

Is there a way that the URCap can be activated/deactivated on the teaching pendant instead, so that the RS-485 port is not blocked by the URCap and can be used by an outside controller? If not, is there a plan to introduce such a feature?

It would be very helpful to be able to access the gripper in certain situations, and it would be strange for the URCap to block this functionality.

bcastets 2020-08-07

Same users directly communicate with the gripper urcap server by sending xml request.

This way you don t need to use rs485 to control the gripper.

You can check this example:
https://dof.robotiq.com/discussion/1962/programming-options-ur16e-2f-85#latest

The commands accepted by the urcap server are not documented in our manuals but you can find it in program script.

felixvd 2020-08-07

You mean sending a urscript containing gripper commands? I have done that in the past, but it is slow and interrupts the script that is running on the robot. For the current ROS UR driver that's not a good option.

bcastets 2020-08-07

I mean sending xml request to urcap server. It is different from sending urscript over client interface.
You can check the code posted on the article. You will understand the process.

felixvd 2020-08-20

Searching for "XML" only refers to the ur_rtde recipes, so I think you meant sending string commands via socket. That is a very helpful link though, thanks! I will continue the discussion over there.