MD5sum Error: Client Topic Datatype Mismatch

Question

I am running the sciurus17 sample code file. After running this launch file, when I try to echo the contents of any /move_group/.... topic, I receive the following error:

[ERROR] [1663154112.847994876]: Client [/move_group] wants topic /move_group/goal to have datatype/md5sum [moveit_msgs/MoveGroupActionGoal/152e336e337dce7cbe639f1bd9c65def], but our version has [moveit_msgs/MoveGroupActionGoal/b7138704cefd43a8dd9758d697350b85]. Dropping connection.
Traceback (most recent call last):
  File "/home/limlab/catkin_ws/devel/lib/sciurus17_examples/pick_and_place_right_arm_demo.py", line 15, in <module>
    exec(compile(fh.read(), python_script, 'exec'), context)
  File "/home/limlab/catkin_ws/src/sciurus17_ros/sciurus17_examples/scripts/pick_and_place_right_arm_demo.py", line 155, in <module>
    main()
  File "/home/limlab/catkin_ws/src/sciurus17_ros/sciurus17_examples/scripts/pick_and_place_right_arm_demo.py", line 19, in main
    arm = moveit_commander.MoveGroupCommander("r_arm_waist_group")
  File "/home/limlab/catkin_ws/src/moveit/moveit_commander/src/moveit_commander/move_group.py", line 66, in __init__
    self._g = _moveit_move_group_interface.MoveGroupInterface(
RuntimeError: Unable to connect to move_group action server 'move_group' within allotted time (5s)

This was working perfectly some time ago while I was running the Move Group C++ Interface Tutorial and suddenly stopped working. I would be very grateful if someone could help me figure this out.

I need to access these topics (more specifically move_group/display_planned_path) in order to find the joint velocity for a particular joint in a path planned by moveit. Any workarounds to achieve this will also be much appreciated.

Setup:

Ubuntu 20.04

ROS noetic

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Originally posted by wuxx959 on ROS Answers with karma: 3 on 2022-09-14

Post score: 0

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Original comments

Comment by Mike Scheutzow on 2022-09-14:
Have you tried typing md5sum into the search box at the top of this page?

Comment by wuxx959 on 2022-09-14:
I tried to synchronize the moveit versions of the two computers but still got this error, I tried to search for mu5dm on the two computers, but the mu5dm on one is all in the env of anaconda, and the other computer has only one mu5dm file

Answer 1

All your ros hosts need to run the same release of ros. This error happens when your nodes are using moveit_msgs from two different versions of ros.

Another possibility is that a source code package in catkin_ws contains a file named MoveGroup.action, and it's from an older version of ros. You need to delete this conflicting moveit_msgs package and use the official one from the /opt/ros/noetic/ tree.

You will need to do a clean build of your catkin_ws after deleting any packages.

update: fixed file name

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Originally posted by Mike Scheutzow with karma: 4903 on 2022-09-15

This answer was ACCEPTED on the original site

Post score: 0

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Original comments

Comment by wuxx959 on 2022-09-15:
Thanks for your answer, I tried removing all moveit packages today and reinstalling moveit, it solved all my problems. thank you very much.