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UR3 URDF modification does not load well in Gazebo

Hi all! I'm quite new to Gazebo and i'm working with an UR3. I'm trying to add an end effector that I created. I managed to make the model with the URDF file, but when I try to load it in Gazebo I get the following error:

[ERROR] [1530088013.617060575, 0.630000000]: Could not find joint 'shoulder_pan_joint' in 'hardware_interface::PositionJointInterface'.
[ERROR] [1530088013.617378163, 0.630000000]: Failed to initialize the controller
[ERROR] [1530088013.617556843, 0.630000000]: Initializing controller 'arm_controller' failed
Error when loading arm_controller
[ERROR] [1530088013.621726505, 0.631000000]: Could not start controller with name arm_controller because no controller with this name exists
Error when starting  ['arm_controller']

And i don't understand why that happens, since the shoulderpanjoint exists and works in the original file that I modified in order to add the end effector. The model loads, but it falls down, here's a picture of it:

image description

If anyone happens to know what's the problem and how to solve it, it would help me a lot. I'm using Ros Kinetic and Ubuntu 16.04. Thank you very much in advance!

Asked by thisyearspairo on 2018-06-27 03:36:19 UTC

Comments

What launch file are you running to load the urdf? Looks like the urdf is spawning just fine, but ros_control is generating ERRORS. I'd also double check to make sure that you made only additive changes - mistakes happen.

Asked by josephcoombe on 2018-06-27 12:30:10 UTC

Hello! Yes, it was a error of deleting something that i shouldn't have, I managed to make it work, but thank you very much for your answer.

Asked by thisyearspairo on 2018-06-28 02:43:13 UTC

Hi I met with the same problem, could you please tell me how to fix it? Much appreciated.

Asked by saltedfish_mountain on 2019-03-17 07:58:38 UTC

Problem fixed. This problem appears because of lacking transmission tab. My robot.xacro file does not contain transmission for the robot. I send the xacro to the parameter server and spawn the robot in gazebo, so this problem appears.

Asked by saltedfish_mountain on 2019-03-17 08:36:47 UTC

Actually I have a robot.urdf file which contains transmission for the robot. So I use the following command in the robot.launch file:

< param name="robot_description" textfile="$(find kuka_kr210_support)/urdf/kr210l150.urdf"/ >

This line send the urdf to the parameter server. It works well. Hope this help others who are struggling with the same problem.

Asked by saltedfish_mountain on 2019-03-17 08:38:24 UTC

Answers