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Exception while calling service of node '<my_node>' : None

asked 2022-02-01 04:08:47 -0500

Fellfalla gravatar image

updated 2022-02-02 04:54:48 -0500

When running navigation2 and then calling ros2 param list, I get following errors:

  • Exception while calling service of node '/bt_navigator_rclcpp_node': None
  • Exception while calling service of node '/controller_server': None
  • Exception while calling service of node '/global_costmap_client': None
  • Exception while calling service of node '/lifecycle_manager_navigation': None
  • Exception while calling service of node '/local_costmap_client': None
  • Exception while calling service of node '/waypoint_follower_rclcpp_node': None

How to reproduce

  1. Copy the foxy navigation 2 launch file into own workspace
  2. Run with the default param file

Environment

  • foxy (0.9.2-1focal.20211119.123452)
  • Ubuntu 20.04

Additional Information

Switching to Galactic yields following (related) error:

Exception while calling service of node '/bt_navigatornavigate_through_poses_rclcpp_node': None
Traceback (most recent call last):
  File "/opt/ros/galactic/bin/ros2", line 11, in <module>
    load_entry_point('ros2cli==0.13.1', 'console_scripts', 'ros2')()
  File "/opt/ros/galactic/lib/python3.8/site-packages/ros2cli/cli.py", line 67, in main
    rc = extension.main(parser=parser, args=args)
  File "/opt/ros/galactic/lib/python3.8/site-packages/ros2param/command/param.py", line 39, in main
    return extension.main(args=args)
  File "/opt/ros/galactic/lib/python3.8/site-packages/ros2param/verb/list.py", line 116, in main
    sorted_names = sorted(response.result.names)
AttributeError: 'NoneType' object has no attribute 'result'
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answered 2022-02-02 03:14:22 -0500

Karl gravatar image

Hi,

the exceptions seems to be thrown here: https://github.com/ros2/ros2cli/blob/... It might be good to open an issue on ros2/ros2cli for that, because the service future returns None although there seems to be no exception set (None).

The reason for this behavior might be that the list_parameters service of the lifecycle nodes you are using is not running or not ready. In which state are the nodes, do they reach configured state?

In general I made the experience that the Nav2 stack is much more mature in ROS2 Galactic.

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Comments

Subscribing to /controller_server/transition_event, It seems like the node is passing following states: 1. unconfigured -> configuring 2. configuring -> inactive 3. inactive -> activating

I wasn't able to find any lifecycle_state topic

Fellfalla gravatar image Fellfalla  ( 2022-02-02 04:38:57 -0500 )edit

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Asked: 2022-02-01 02:53:59 -0500

Seen: 323 times

Last updated: Feb 02