Hello ZED community,
I hope this message finds you well. I am currently working on a project involving the ZED ROS2 wrapper for a ZED 2i camera. As a mechanical engineering undergraduate with limited experience in ROS2, I am facing a challenge with QoS compatibility between the ZED ROS2 wrapper and a custom node.
The goal of the project is to convert the ZED ROS2 wrapper’s PointCloud2 data from the topic ‘/zed/zed_node/point_cloud/cloud_registered’ based on a white threshold value detected by the camera. The custom node, named ‘point_cloud_filter_node’, is designed to filter out all points below this threshold and publish only the white points on the topic ‘/filtered_pointcloud’, which is visualized in rviz.
However, when I run my custom node alongside the ZED 2i display node using the command:
ros2 launch zed_wrapper zed_camera.launch.py camera_model:=zed2i
ros2 run zed_filter point_cloud_filter_node
I encounter the following warning messages:
[WARN] [1706664156.580546320] [rviz]: New publisher discovered on topic ‘/filtered_pointcloud’, offering incompatible QoS. No messages will be sent to it. Last incompatible policy: DURABILITY_QOS_POLICY
[WARN] [1706664161.226727560] [rviz]: New publisher discovered on topic ‘/filtered_pointcloud’, offering incompatible QoS. No messages will be sent to it. Last incompatible policy: DURABILITY_QOS_POLICY
In an attempt to resolve this, I set the QoS profile in my ‘point_cloud_filter_node’ with the desired durability policy:
However, it seems that I might also need to set the durability for the ZED ROS2 wrapper. Unfortunately, my limited experience with ROS2 makes it challenging for me to identify the specific location in the ZED ROS2 wrapper code where I should modify the QoS settings for durability.
I would greatly appreciate any guidance or assistance you can provide in resolving this issue. If there’s an alternative approach to achieve the goal of visualizing only the white data points in rviz, I am open to suggestions.
Thank you for your time and support.
Best regards,
Harsh Shah
Undergraduate in Mechanical Engineering