Lyrical to M-Turtle

Migration Actions and Deprecations

Behavior Server plugin parameters are now namespaced

The behavior plugins' parameters are now declared under the plugin's name from behavior_plugins, in the same way the acceleration_limit, deceleration_limit and minimum_speed parameters of BackUp and DriveOnHeading already were. The old node-level names are no longer read, so existing configurations must be updated or the defaults will silently apply:

Old (node-level)	New (per plugin)
simulate_ahead_time	spin.simulate_ahead_time, backup.simulate_ahead_time, drive_on_heading.simulate_ahead_time
max_rotational_vel	spin.max_rotational_vel
min_rotational_vel	spin.min_rotational_vel
rotational_acc_lim	spin.rotational_acc_lim
projection_time	assisted_teleop.projection_time
simulation_time_step	assisted_teleop.simulation_time_step
cmd_vel_teleop	assisted_teleop.cmd_vel_teleop

Substitute your own plugin names if they differ from the defaults. Simply move the parameter under the plugin's declaration in your configuration.

Single Lifecycle Manager in Nav2 Bringup

PR #6410 combines the separate lifecycle managers for localization, navigation, SLAM, keepout zones, speed zones and the loopback simulator into a single lifecycle_manager_nav2, started by bringup_launch.py. Measured on the Turtlebot 4 simulation launch, which previously ran four lifecycle managers, this reduces Nav2's CPU use by around 25%. The nested launch files in nav2_bringup no longer start a lifecycle manager of their own. Each has a get_lifecycle_nodes(context) function that returns its lifecycle node names, which bringup_launch.py collects into the node_names of the single manager.

Launching a nested file by itself, such as ros2 launch nav2_bringup navigation_launch.py, now leaves the servers unconfigured. Launch bringup_launch.py instead and use its arguments to turn off what you do not need, for example use_localization:=False when SLAM or another source provides the map and the map to odom transform. Anything that used the old manager names, such as lifecycle_manager_navigation/manage_nodes, should use lifecycle_manager_nav2 instead; the Nav2 RViz panel is already updated.

Move your own nested launch files to the same pattern: remove the lifecycle manager from each one, add a get_lifecycle_nodes(context) function that returns its lifecycle node names, and build the node_names of your single manager from those functions plus your own nodes. The task server tutorial shows this.

If you would rather run a launch file on its own, start a lifecycle manager beside it.

New Features and Improvements

Static Layer Overlays Without Resizing the Master

PR #6488 adds the Static Layer parameter resize_master, which defaults to true. Existing configurations require no changes: a Static Layer still resizes a non-rolling master costmap to match its incoming map.

Set resize_master: false for additional Static Layers whose maps should not control the master's geometry. For example, a Vector Object Server can publish an obstacle map with a smaller or changing extent while the primary Static Layer continues to own the site map geometry.

Assisted Teleop Times Out on Stale Teleop Commands

The AssistedTeleop behavior now stops the robot and fails the action with the new TELEOP_INPUT_TIMEOUT error code (733) when no teleop command has been received within the new teleop_command_timeout parameter (default 0.25 s).