highmax1234's profile - activity

Following the trace of the command line ros2 topic info leads us here: https://github.com/ros2/ros2cli/blob/f4e5952f430e

Following the trace of the command line ros2 topic info leads us here: https://github.com/ros2/ros2cli/blob/f4e5952f430e

Following the trace of the command line ros2 topic info leads us here: https://github.com/ros2/ros2cli/blob/f4e5952f430e

Following the trace of the command line ros2 topic info leads us here: https://github.com/ros2/ros2cli/blob/f4e5952f430e

Speaking for ros2 since I don't know for ros1, you can just open the sql database and select all the topics you want wit

ros2 launch or python3 foo.launch.py I see several example launch files which implement a main, instead of just returnin

ros2 launch or python3 foo.launch.py I see several example launch files which implement a main, instead of just returnin

ros2 launch or python3 foo.launch.py I see several example launch files which implement a main, instead of just returnin

If you are using "raw" discovery without a fastdds discovery server, your switch/router will need to forward UDP Broadca

You can spawn another node within your node, create a new thread for it to do an asynchronous service call and then shut

You will need a controller and a gazebo plugin. The controller can be either within the plugin or separate in a ros2 nod

You will need a controller within a gazebo plugin. You can find examples on gazebo plugins in this repo: https://github.

in python you can use cli.service_is_ready() But I see that this function sometimes needs to be called repeatedly until

You have multiple possibilities, the easiest being a vpn. This one is easy to set up: https://vpncloud.ddswd.de/ You c

You can spawn another node within your node to do an asynchronous service call and then shut it down again.

Hi,

I want to use the rclpy module in a python script. This script is called by a flask application which is invoked by an apache2 webserver and does not get the necessary bash context. When I run the python script from bash with python3 foo.py everything works fine, as I have . /opt/ros/foxy/setup.bash in my ~/.bashrc .

When the script gets invoked by flask and apache2, import rclpy is not found. Exeucting sys.path.insert("/opt/ros/foxy/lib/python3.8/site-packages/") brings another error:

The C extension '/opt/ros/foxy/lib/python3.8/site-packages/rclpy/_rclpy.cpython-38-x86_64-linux-gnu.so' failed to be imported while being present on the system. Please refer to 'https://index.ros.org/doc/ros2/Troubleshooting/Installation-Troubleshooting/#import-failing-even-with-library-present-on-the-system' for possible solutions

There has been a similar Thread with no solution. The essence seems to be that opt/ros/foxy/setup.bash does more than just setting paths.

Now, is there any possibilty to use rclpy in a python script without sourcing from bash? Thanks

Ubuntu 20.04
ROS2 foxy

I tried exporting, but it is not enough for sourcing ros. The setup.bash does more than setting env variables. I did som

Hello, I followed this tutorial to set up a discovery server for ros2. The talker and listener examples all worked fine.

However, when it came to

ros2 topic list

ros2 node list

export ROS_DISCOVERY_SERVER=127.0.0.1:11811

It seems like this is enough for talker and listener nodes to find each other, but not for ros2 command line tools. Also, rqt did not show any nodes or topics either. Command line tools and rqt work fine with standard discovery.

Is there anything else I need to do for ros2 topic list to show the /chatter topic?

The corresponding issue mentions this question and can be followed under this link: https://discourse.ros.org/t/discover

I want to launch a component into an existing container. Can anybody help me with this error?

As far as I can see, my code is identical with image_pipeline/stereo_image_proc/launch/stereo_image_proc.launch.py , which uses LoadComposableNodes too. However, the foxy branch does not contain this action anymore. Is it maybe deprecated in foxy? Is there an alternative?

When I run a container in bash#0 with

ros2 run rclcpp_components component_container

and then execute the following launch file in bash#1:

#!/usr/bin/python3
import launch
import launch.actions
import launch.substitutions
from launch_ros.descriptions import ComposableNode
from launch_ros.actions import LoadComposableNodes

def generate_launch_description():
    ld = launch.LaunchDescription()
    comp_node = ComposableNode(
                package="composition",
                plugin="composition::Talker",
                name='compose_name',
                namespace='compose_namespace',
                parameters=[],
                remappings=[],
            )

    load_component = LoadComposableNodes(
        composable_node_descriptions=[comp_node],
        target_container='/ComponentManager'),

    ld.add_action(load_component)
    return ld

I get the following error:

ros2 launch src/my_package/launch/test.launch.py 
[INFO] [launch]: All log files can be found below /home/user/.ros/log/2021-05-11-21-28-08-187318-ROS_WS-2144061
[INFO] [launch]: Default logging verbosity is set to INFO
Task exception was never retrieved
future: <Task finished name='Task-2' coro=<LaunchService._process_one_event() done, defined at /opt/ros/foxy/lib/python3.8/site-packages/launch/launch_service.py:274> exception=AttributeError("'tuple' object has no attribute 'describe_sub_entities'")>
Traceback (most recent call last):
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/launch_service.py", line 276, in _process_one_event
    await self.__process_event(next_event)
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/launch_service.py", line 296, in __process_event
    visit_all_entities_and_collect_futures(entity, self.__context))
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/utilities/visit_all_entities_and_collect_futures_impl.py", line 45, in visit_all_entities_and_collect_futures
    futures_to_return += visit_all_entities_and_collect_futures(sub_entity, context)
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/utilities/visit_all_entities_and_collect_futures_impl.py", line 45, in visit_all_entities_and_collect_futures
    futures_to_return += visit_all_entities_and_collect_futures(sub_entity, context)
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/utilities/visit_all_entities_and_collect_futures_impl.py", line 38, in visit_all_entities_and_collect_futures
    sub_entities = entity.visit(context)
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/action.py", line 108, in visit
    return self.execute(context)
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/actions/include_launch_description.py", line 140, in execute
    declared_launch_arguments = launch_description.get_launch_arguments()
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/launch_description.py", line 126, in get_launch_arguments
    process_entities(self.entities, _conditional_inclusion=conditional_inclusion)
  File "/opt/ros/foxy/lib/python3.8/site-packages/launch/launch_description.py", line 120, in process_entities
    entity.describe_sub_entities(), _conditional_inclusion=False)
AttributeError: 'tuple' object has no attribute 'describe_sub_entities'

Turns out it works when I use Launch Configuration: #!/usr/bin/python3 import launch import launch.actions import launc