Running RTABMAP simulation on the new gazebo with ros2 Jazzy

[usman]

Hi everyone
Has anyone been able to run RTAB-MAP simulation on the new Gazebo? I can carry out mapping successfully, but I have issues with:
1. Localization: When the map loads in RVIZ, turtlebot is placed in its last known position during the mapping stage; meanwhile, in Gazebo, the robot spawns in its start position. This causes the current laser scan to not match the map (see attached image; the incomplete scan shows the scan coming from the robots actual position I Gazebo)
2. Autonomous navigation: turtlebot does not move when I give it a goal pose

I am using ros2 Jazzy and the new Gazebo with the codes on the RTAB-MAP demo repo here.
The only changes I made are the remappings of the following topics
    remappings=[
          ('scan', '/scan'),
          ('rgb/image','/camera/image_raw'),
          ('rgb/camera_info','/camera/camera_info')

[matlabbe]

There is a comment on top of the demo launch file about increasing min range of the lidar to avoid hitting itself, which may block nav2 to move.

I re-tested the demo on Humble:

ros2 launch rtabmap_demos turtlebot3_sim_scan_demo.launch.py

The 2D Goal button should work:


End of mapping:


After restarting the simulator in localization mode:

ros2 launch rtabmap_demos turtlebot3_sim_scan_demo.launch.py localization:=true

In lidar-only setup, the robot cannot globally localize (it needs a camera to do so), it can only locally re-localize. With rviz, you can send a 2d Pose estimate around where you expect the robot to be in the map:


Once the robot will be moving, it should refine its localization against the map so that the laser scan perfectly align with the occupancy grid:


Note that if you want the robot to always restart at the initial position in the simulator, you could add parameter RGBD/StartAtOrigin to false for rtabmap node.

cheers,
Mathieu

[usman]

Hi Mathieu,

Thank you for your response. Here’s an update on my progress with ROS 2 Jazzy and the new Gazebo simulator:

1.    2D Pose Estimate: Works correctly for setting the robot’s initial pose.

2.    RGBD/StartAtOrigin: Setting this to True works perfectly; the robot now spawns at the origin in RViz.

3.    Autonomous Navigation Issue with TurtleBot3: I’ve adjusted the minimum LiDAR scan value to 0.2, but autonomous navigation still fails when a goal pose is given. Interestingly, navigation works correctly when I use the MOBO_BOT package (which includes a complete robot description and navigation scripts).

 I’ve identified two key differences so far:

##          MOBO_BOT includes a gz_bridge parameter file, which appears necessary for compatibility with the new Gazebo simulator.

##          The default Nav2 configuration, when used with Turtlebot_3, publishes only to the cmd_vel_nav instead (nothing is published on the cmd_vel topic), and the messages are not timestamped. The new Gazebo simulator requires the twist messages to be timestamped and on the cmd_vel topic. I hope to share more updates when I get it working with turtlebot_3 on the new Gazebo simulator and ROS2 Jazzy.

4.   Finally, when working with 2D LiDAR SLAM, I experimented with setting the 'use_rgb' parameter to 'true', and it eliminated/reduced drift significantly after loop closures.