QoS incompatibility between the navsat_transform node and the ekf_filter node

[GPrathap]

Desktop (please complete the following information):

• OS: Ubuntu 22.04
• ROS Distribution: Humble

To reproduce this behaviour

1. ros2 topic info -v /odometry/global where /odometry/global is the global odometry estimation topic from ekf_filter

       Publisher count: 1
       Node name: ekf_filter_node_map
       Node namespace: /
       Topic type: nav_msgs/msg/Odometry
       Endpoint type: PUBLISHER
       GID: 01.10.90.de.c2.02.9b.31.57.de.c5.4d.00.00.28.03.00.00.00.00.00.00.00.00
       QoS profile:
         Reliability: RELIABLE
         History (Depth): KEEP_LAST (10)
         Durability: VOLATILE
         Lifespan: Infinite
         Deadline: Infinite
         Liveliness: AUTOMATIC
         Liveliness lease duration: Infinite
   

   Subscription count: 2

   Node name: navsat_transform_base
   Node namespace: /
   Topic type: nav_msgs/msg/Odometry
   Endpoint type: SUBSCRIPTION
   GID: 01.10.42.3d.a3.e1.64.b1.da.72.99.8a.00.00.22.04.00.00.00.00.00.00.00.00
   QoS profile:
     Reliability: BEST_EFFORT
     History (Depth): KEEP_LAST (1)
     Durability: VOLATILE
     Lifespan: Infinite
     Deadline: Infinite
     Liveliness: AUTOMATIC
     Liveliness lease duration: Infinite
   

I feel that within ekf_filter node for the odometry topic QoS type should be BEST_EFFORT, VOLATILE.

[GPrathap]

@ayrton04 If we configure this way will it solve the problem? https://docs.ros2.org/galactic/api/rclcpp/classrclcpp_1_1QosOverridingOptions.html

[GPrathap]

Seems to be when I set this it working fine :)

    ekf_filter_node_map:
      ros__parameters:
        qos_overrides:
          /odometry/global:
            publisher:  # publisher without provided id
              reliability: best_effort
              depth: 1

[ayrton04]

I don't use this node in ROS 2, so I don't feel strongly. Is it actually causing any performance issues?

[GPrathap]

Yep, over DDS, especially with Cyclone DDS. But, after ordering it's fine

[ayrton04]

And why change the EKF settings and not the QoS profile in navsat_transform_node?

[GPrathap]

Have look here: https://docs.ros.org/en/foxy/How-To-Guides/DDS-tuning.html

Solution: Use best-effort QoS settings instead of reliable.

navsat_transform_node already publishes with best-effort QoS

[ayrton04]

Okie doke. I won't be making any changes, but feel free to submit a PR. Thanks.