Updating ros controller_manager_msgs to melodic

I have controller_manager running on ros melodic. When I try to use its services from Matlab, I get the following error

[ERROR] [1591000198.922306771]: client wants service /controller_manager/switch_controller to have md5sum 5e857dedf71d6f337975e15a1e7cfdd8, but it has b29a7abc673b2c54c14b54e50f8d06a5. Dropping connection.

Some of the definitions of the controller_manager_msgs changed from kinetic to melodic. See diff of controller_manager_msgs/srv/SwitchController.srv at https://github.com/ros-controls/ros_control/compare/kinetic-devel...melodic-devel#diff-1e2186b2d201088ea127dd088546d83d

When I try to follow https://www.mathworks.com/matlabcentral/answers/283695-updating-existing-custom-message-types-with-rosgenmsg

and https://www.mathworks.com/matlabcentral/answers/500397-updating-ros-messages-for-moveit (to change package.xml to the legacy format), I still get the error:

>> rosgenmsg('/path/to/MATLAB/melodic_msgs')

Checking subfolder "controller_manager_msgs" for custom messages.

Building custom message files for the following packages:

controller_manager_msgs

Generating MATLAB classes for message packages in ../MATLAB/melodic_msgs/matlab_gen/jar.

Output argument "msgFolder" (and maybe others) not assigned during call to "ros.custommsg.internal/CustomMessageLoader/loadMessages".

When I renamed controller_manager_msgs to something else, the messages were generated sucessfully. It seems that updating message definitions does not work for core messages that come already included in Matlab (with rosjava). Is there any workaround except for deleting old messages system-wide?

MATLAB Version: 9.7.0.1190202 (R2019b)

Answer 1

[Jagadeesh Konakalla]

Hi Mihael Simonic,

Can you take a look at the following MATLAB answer ? Let me know if the solution does not work for you

https://www.mathworks.com/matlabcentral/answers/283695-updating-existing-custom-message-types-with-rosgenmsg.

[Mihael Simonic]

I already referred to this answer in my question. Following this procedure does not work for me. It seems that my bug only applies to the messages already included in rosjava jars shipped with matlab. Other messages that are shipped in separate jars seem to work fine.