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Does the UR controller (CB3/UR10) provide any feedback (such as move complete/acknowledgement ) given trajectory commands from ur_modern_driver through ROS or UR script commands directly such as movej?
I read from this link : https://github.com/ThomasTimm/ur_mode...
There's no way to detect whether "the script" has finished. That is a limitation of the infrastructure provided by UR, not of the driver btw
Quoting myself in #q285090:
The
ur_modern_driverexposes a FollowJointTrajectory action server. As the name implies, that server accepts goals containing a JointTrajectory.
Interacting with an action server is done by writing an action client. This interaction can be both synchronous (ie: blocking) and asynchronous (ie: non-blocking). The former only returns when a trajectory has completed, the latter returns immediately.
I'd suggest you review the wiki/actionlib documentation and do some of the tutorials. That should provide you with some insight.
Edit: note that ur_modern_driver does not directly use URScript when executing a trajectory. The limitations mentioned by Thomas only apply when sending script snippets to the controller over the /urscript topic.
Edit2: see also the test_move.py Python script that implements a very rudimentary action client to control the robot through the driver.
Finally: please realise that using Actions to interact with robot drivers is not specific to ur_modern_driver at all. It's a fundamental piece of infrastructure in ROS. Getting good understanding of Actions is paramount if you want to create a serious application with ROS.
Sending movej statements to /urscript seems strange to me. Why do you do that? If you're not going to use the trajectory action server, why use the driver in the first place?
the script commands seem to take priority
they don't take priority per se, but the ctrlr terminates the driver.
Asked: 2018-03-14 02:47:27 -0500
Seen: 656 times
Last updated: Mar 14 '18
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May I suggest a title change? Your question is about feedback, but when talking about robots and controllers, most people will understand this as meaning position or velocity feedback. Your question is really more about control flow synchronisation and action completion.