text_nav_bridge

Text-command-driven robot navigation for ROS 2. Reads text landmarks generated by TextMap (Phase 1) and converts user text commands into Nav2 NavigateToPose actions.

Dependencies

• ROS 2 (tested on Humble; source compiles on Iron/Jazzy/Kilted/Rolling)
• navigation2
• rtabmap_ros
• textmap (provides shared text_similarity.hpp)
• yaml-cpp, tf2, rclcpp_action

sudo apt install ros-${ROS_DISTRO}-navigation2 ros-${ROS_DISTRO}-nav2-bringup ros-${ROS_DISTRO}-rtabmap-ros

Build

cd ~/ros2_ws
colcon build --packages-select text_nav_bridge
source install/setup.bash

Usage (Phase 2: Navigation)

Requires Phase 1 outputs: rtabmap_db/<bag_name>.db (map) and landmarks/<bag_name>.yaml (text landmarks).

1. Launch navigation stack

ros2 launch text_nav_bridge text_nav.launch.py bag_name:=rosbag2_2026_01_08-15_03_00

A single bag_name argument resolves both the landmark file and rtabmap DB:

• src/text_nav_bridge/landmarks/<bag_name>.yaml
• src/text_nav_bridge/rtabmap_db/<bag_name>.db

2. Play rosbag or run real camera

# Rosbag
ros2 bag play <your_bagfile> --clock

# Or real camera
ros2 launch rtabmap_ros realsense_infra_for_record.launch.py

Spawns RTAB-Map localization (loading the bag's .db) + Nav2 + text_nav_bridge + RViz.

3. Send a text command

ros2 topic pub --once /text_nav/command std_msgs/msg/String "data: 'restroom'"

The node will:

1. Find the best matching landmark from landmarks.yaml
2. Ray-march along the robot-to-landmark line on the Nav2 /map costmap and pick the last free cell as the navigation goal
3. Send a NavigateToPose goal to Nav2

4. Monitor status

ros2 topic echo /text_nav/status

data: "NAVIGATING: heading to 'restroom'"
data: "NAVIGATING: distance_remaining=2.31m"
data: "SUCCESS: Navigation completed"

Launch Arguments

Argument	Default	Description
bag_name	(required)	Rosbag name (e.g. rosbag2_2026_01_08-15_03_00)
use_sim_time	true	Use simulation time (true for rosbag)
data_dir	resolved from install share	Directory containing landmarks/ and rtabmap_db/
match_threshold	0.5	Text similarity threshold (0~1)
robot_frame	camera_link	Robot base frame id
world_frame	map	World/map frame id
static_tfs_file	<pkg>/config/realsense_d455_tfs.yaml	YAML of static TFs to inject (see realsense_d455_tfs.yaml for the schema). Pass '' when /tf_static is already provided by the bag or camera driver.

Topics

Subscriptions

Topic	Type	Description
/text_nav/command	std_msgs/String	Text command to navigate to
/map	nav_msgs/OccupancyGrid	Costmap used for ray-march goal selection (transient_local)

Publications

Topic	Type	Description
/text_nav/status	std_msgs/String	Navigation status updates
/text_nav/goal_marker	visualization_msgs/Marker	Goal visualization in RViz
/textmap/markers	visualization_msgs/MarkerArray	Loaded landmarks republished for RViz (1 Hz)

RViz config: rviz/text_nav.rviz.

License

Apache License 2.0