how to generate the custom message

I am trying to creat a message for ros in maltab.

the .msg filein the folder (/home/bikebot/catkin_ws/src/kinova-ros-master/kinova_msgs/msg) and under the folder there are multiple .msg files.

then I used the funciton rosgenmsg and got followign error.

folderpath ='/home/bikebot/catkin_ws/src/kinova-ros-master/kinova_msgs'

rosgenmsg(folderpath)

Identifying message files in folder '/home/bikebot/catkin_ws/src/kinova-ros-master/kinova_msgs'..Done.

Validating message files in folder '/home/bikebot/catkin_ws/src/kinova-ros-master/kinova_msgs'..Done.

[0/0] Generating MATLAB interfaces for custom message packages... Done.

Error using rosgenmsg (line 332)

No packages with '.msg' files found under

/home/bikebot/catkin_ws/src/kinova-ros-master/kinova_msgs. Each message package directory must

contain a directory named 'msg' that then contains '.msg' files.

Hope someone can help with this.

Answer 1

[Cam Salzberger]

This is the same issue as here. Please see that question and this one for more folder structure details.

-Cam

[Feng Han]

Thanks. The problem is that the custom message package cannot be intalled in MATLAB 2020b on linux. I installed it on 2020a and it works now.

Feng

[Cam Salzberger]

I'm not sure what you mean by the custom message package not being able to be installed in R2020b. The vast majority of message definitions should work with either R2020a or R2020b. Off the top of my head, the only issues I can think of that would be usable in 20a but not 20b is if the message definition uses a reserved C++ keyword as a message or field name.

Can you provide more detail? Maybe with your message definition(s) if you can share it?

[Feng Han]

Thanks. I already solved this problem.

Answer 2

[can ren]

Did you encountered the following problems?

[Cam Salzberger]

For up to and including R2020b, ROS Toolbox only supports Visual Studio 2017 for custom message generation on Windows. For R2021a, it also supports Visual Studio 2019. Assuming you are using an earlier release of MATLAB, install VS2017 and use mex -setup to point to it. Or update to R2021a.

See here for the R2021a system requirements page.

-Cam