[Unitree GO2 EDU] AMCL dropping LiDAR messages — “Message Filter dropping message: frame 'lidar_link' … reason 'Unknown'” during map navigation

Software
1

Robot: Unitree Go2
Software: ROS 2 Foxy
Navigation Stack: Nav2 (map_nav.launch.py)

Issue Summary

When launching map navigation (map_nav.launch.py), AMCL fails to process LiDAR data. The console repeatedly shows:

[amcl-2] [INFO] [1759320184.032145958] [amcl_rclcpp_node]: 
Message Filter dropping message: frame 'lidar_link' at time 1759320074.145 for reason 'Unknown'

What Has Been Tried

  • Verified that lidar_link is defined correctly in the URDF.
  • Confirmed /go2_unit_38798/scan is publishing LiDAR data.
  • Checked AMCL parameters:
    base_frame_id: base_link
    odom_frame_id: odom
    global_frame_id: map
    scan_topic: /go2_unit_38798/scan
    transform_tolerance: 1.0

Please can someone help me to debug this error!

2

Good Morning,

This is a warning. If Amcl is working correctly, there should not be much of an issue. It could be the lidar scan time mismatch, missing TF transform, incorrect anemespace, or mismatch of link name.

If AMCL is correctly localizing, then it should be fine.

3

Thank you for the reply. Is there a way to debug the AMCL because I think it’s not working properly

4

It can be done via the cli tools e.g.:

ROS_DOMAIN_ID=10 ros2 topic info topic_name
ROS_DOMAIN_ID=10 ros2 topic info node_name

etc.