Ros2 in 5 days (python): rosject attribution error

[zcccccc]

After setting up the wall_follower package correctly, “ros2 launch wall_follower start_wall_following.launch.py” failed with the message “AttributeError: type object ‘type’ has no attribute’_TYPE_SUPPORT’ This might be a ROS 1 message type but it should be a ROS 2 message type. Make sure to source your ROS 2 workspace after yourROS 1 workspace.”

Note the launch command is only executed with the bridge running in another terminal and after executing “source /opt/ros/noetic/setup.bash” and “source ~/simulation_ws/devel/setup.bash” in a new terminal. Teleop is terminated at the time of launch (but runs correctly). Could anyone help please?

[girishkumar.kannan]

Hi @zcccccc ,

Welcome to this Community!

This is a common problem which you can find in the forums.
The solution is to source ROS1 and then ROS2.

So the steps are:

1. Source ROS1 : source /opt/ros/noetic/setup.bash
2. Source ROS2 : source /opt/ros/foxy/setup.bash
3. Now build your package from ros2_ws path :
   colcon build --packages-select <your_package_name>
4. Source your workspace : source install/setup.bash
5. Now you can run your program :
   ros2 launch wall_follower start_wall_following.launch.py

Don’t forget to have your simulation running in one of the shells.
Since your are working on ROS2, you need to have these running in terminals:
Teminal 1 : Simulation
Terminal 2 : ROS Bridge
Terminal 3 : This is where you launch your program.

Hope this helps you. Let me know if this dis not work.

Regards,
Girish

[zcccccc]

@girishkumar.kannan

ros2 launch wall_follower start_wall_following.launch.py

Thank you so much! Unfortunately, these steps were unable to fix the issue, I have attached screenshots to give a clearer picture.

[zcccccc]

[zcccccc]

[girishkumar.kannan]

Hi @zcccccc ,

The terminals that you get on ROS2’s rosject are by default sourced with ROS2.
So you don’t have to source ROS1 and ROS2 in a new terminal - only on ROS2 rosjects (Python / C++).
You can directly build your packages.

You must be in ~/ros2_ws before building a package.

cd ~/ros2_ws
colcon build --packages-select <your_package_name> && source install/setup.bash
ros2 launch <package_name> <launch_file_name>.launch.py

Let me know if this fixes your problem!

Regards,
Girish

[zcccccc]

@girishkumar.kannan

ros2 launch <package_name> <launch_file_name>.launch.py

It worked!! Thank you so much! This issue bothered me for several days now.

[girishkumar.kannan]

Hi @zcccccc ,

Glad you got this working.

I must say, these instructions are clearly written in the rosject (jupyter) notebook.

Regards,
Girish

PS: Mark this problem as solved so this issue can be closed!