[ERROR] : Group 'arm' is not a chain
Cross-posted on Github here.
I am a beginner in ROS. I wrote an urdf file and generated demo.launch with moveit setup assisient. When I roslaunch it, the following error occurred:
[ERROR] [1617752615.735037382]: Group 'arm' is not a chain`[ERROR] [1617752615.735223971]: Kinematics solver of type 'kdl_kinematics_plugin/KDLKinematicsPlugin' could not be initialized for group 'arm'
[ERROR] [1617752615.735414230]: Kinematics solver could not be instantiated for joint group arm.
[ WARN] [1617752615.850870497]: The root link base_link has an inertia specified in the URDF, but KDL does not support a root link with an inertia. As a workaround, you can add an extra dummy link to your URDF.
[ERROR] [1617752616.291773005]: Client [/move_group] wants topic /move_group/goal to have datatype/md5sum [moveit_msgs/MoveGroupActionGoal/689f0d7213d5960a2a9e9b117a0fdb73], but our version has [moveit_msgs/MoveGroupActionGoal/6514728724a6f4ce3f2f5a26db255bc9]. Dropping connection.
[ERROR] [1617752645.935486956]: Unable to connect to move_group action server 'move_group' within allotted time (30s)
Please add the error message to the body of your question and fix the title.
I'm going to guess it's "group 'arm' is not a chain".
Yes,but I'm afraid I can't upload my urdf and srdf because I have no 5 points
You do now, but it looks like you need to clean your workspace and check why your arm is not a chain. Most likely you included multiple fingers of a gripper.
It's not working.My urdf and srdf are here.
Anyone can help me？
Did you try removing the inertia from the base link and fixing the other errors? It seems like your versions don't match or you are building parts of moveit from source but not others. I don't see anything obviously wrong in the SRDF/URDF, but a picture would help. I might also try removing the gripper chain and end effector from the SRDF for debugging.
Thanks for your help!