I get an error when I try to execute a launch file in unit 3 : basics

Course Support ROS Basics In 5 Days (C++)
1

I compiled the package successfully using catkin_make and then I tried exceuting it. I got the following error :
RLException: Unable to launch [ObiWan-1].
If it is a script, you may be missing a ‘#!’ declaration at the top.
The traceback for the exception was written to the log file

2

Hi @mouidsakka01 ,

Welcome to this Community!

C++ programs do not require a shebang declaration, that is, the #! that the error message is specifying to you.

I have finished this course, so I am assuming that you have just started this course and you are working on the my_package which has the ObiWan node name.

I believe that you might have mistake in your launch file (since this is the very first package you create in the course and there are no modifications required for CMakeLists.txt file and package.xml file).

Please post your launch file contents here as a code-block.
Refer how to make a code-block from here: Extended Syntax | Markdown Guide

Regards,
Girish

1 Like
3

That’s right! I had a small mistake in my launch file . Instead of typing in the type “simple” , I typed “simple.cpp” , but it probably wants only the name of the source file without extension.
Thank you for the answer. I am happy and excited to join the community and the world of robots :slight_smile: !

4

Hi @mouidsakka01 ,

Glad to know that I was of help and you got your problem resolved!

Regards,
Girish