Linefollowing of drone

hello there, iam working on line following drone. the issue is the the gazebo simulation environment got lines and drone but when i run the code "rosrun my_following_line_package" and the drone isn’t following the line instead it just moves straight(like as if it isn’t detecting any line). i have attached my rosject below. It would be great if someone can have a look and let me know what iam missing on!! thank you in advance.

I have copied your rosject and launched it. Then opened a terminal and issued the command that you mentioned: rosrun my_following_line_package

user:~$ rosrun my_following_line_package
Unable to register with master node [http://4_xterm:11311]: master may not be running yet. Will keep trying.

The command fails, of course, because there is no simulation.
I have checked the notebook included in the rosject but has no instructions at all. So I could not reproduce your problem.

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