text_nav_sim

Gazebo simulation environment: world, URDF, TurtleBot3 Waffle (RGB-D) model, text signs and ad banner props. Launches Gazebo only; mapping and navigation pipelines are run separately — see textmap and text_nav_bridge.

Dependencies

• ROS 2 Humble
• gazebo_ros, turtlebot3_gazebo
• robot_state_publisher, tf2_ros

Build

source /opt/ros/humble/setup.bash
colcon build --packages-select text_nav_sim
source install/setup.bash

Usage

ros2 launch text_nav_sim simulation.launch.py

Spawns Gazebo with the house world + waffle_rgbd robot and publishes the camera_rgb_frame → camera_rgb_optical_frame static TF.

Launch Arguments

Argument	Default	Description
use_sim_time	true	Use simulation clock
world_file	<pkg>/worlds/turtlebot3_house_signs.world	Gazebo world
spawn_x / spawn_y / spawn_z	-6.5 / -1.0 / 0.01	Spawn position
spawn_yaw	-1.5708	Spawn yaw (rad)

Models

Text signs (Z=1.8m, black text on white): Exit, Kitchen, Bathroom, Bedroom, Office, Garage, Closet, Living Room, Laundry, Storage Room.

Four ad banners (Z=1.9m) use low-contrast text against colored backgrounds as OCR-suppression test cases.

Robot: TurtleBot3 Waffle with RGB-D camera — see urdf/turtlebot3_waffle_rgbd.urdf. Camera topics: /camera/rgbd_camera/image_raw, /camera/rgbd_camera/depth/image_raw (32FC1 m), /camera/rgbd_camera/camera_info.

Troubleshooting

spawn_entity.py hangs / odom frame does not exist

Previous gzserver is still running. Kill it before relaunching:

killall -9 gzserver gzclient; pkill -9 -f ros2

conda Python conflict

If (base) conda environment is active, spawn_entity.py fails due to Python version mismatch (needs 3.10, not 3.13). Deactivate conda first:

conda deactivate