Universal Robots+

ROS subscriber or action listener node on UR for geometry msg twist

My goal is to make the UR3e react to the movement of a MPU9250 (gyroscop, accelerometer and magnetometer hooked up to an arduino) If possible I would like the robots tool center point to mimic the motion of the MPU9250 in 3D space. I do not have a Gripper or tool attached to the Robot, I would like to move the position and orientation of the wrist though.

I followed enough tutorials to be able to run a ROS node on the Arduino to process data from the gyroscope and send TF data or gemometry_msgs to Turtlesim. (The turtle moves when the gyroscop is moved)

I have installed ROS melodic, RosIndustrial and the Universal_Robots_ROS_Driver driver. The github instructions for establishing communication via ethernet worked. (ROS can “ping” the robot) Unfortunately I have no idea how to translate the 2D simulation into actual robot movements.

  • How do I write a basic subscriber node or action listener to run on the UR? (Are there any tutorials or demos about this? )
  • Do I need some special algorythms to translate geometry_msgs to the pose of the UR?
  • Are there some good functions, libraries or frameworks for me to look into?

I’m a s student (Junior) working on my bachelors degree in software engineering. This project is part of my internship with a robotics departement in an actual company. I’m new to ROS and this is my first time working with an UR robot. I would ask my co workers if they had experience working with UR and ROS.

The interesting part is to generate motion commands from this TF data. From your generated pose you would have to derive a valid joint command (as we are currently only supporting commands in joint space) and send this to the robot.

However, as we use ROS-Control in the driver you can use other ROS-Controllers with the driver, as well. For instance, there is the cartesian_controllers package maintained by a colleague which does exactly that. You would have to add this package to your workspace, recompile and setup the respective controllers as explained in the package’s documentation.

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