ROSbot 3 - ROS 2 API

Detailed information about content of rosbot package for ROS2.

Control

Gamepad

After running the ROSbot XL Manipulation Package, you should be able to control the manipulator. The easiest way to move the manipulator is to connect a gamepad and steer the robot. The graphic below shows how to steer the manipulator using a gamepad.

Drive controls (cmd_vel) are defined in rosbot_joy/config/config.yaml. The manipulator gamepad mappings (XL only) are hardcoded in rosbot_moveit/src/joy2servo.cpp.

ROS API

Namespace policy

Everything below is published under /<namespace>/ when the namespace launch arg (or ROBOT_NAMESPACE env) is set. Intentional globals:

• /tf, /tf_static — bridged via tf_namespace_bridge.
• /parameter_events, /rosout — ROS 2 infra.
• /clock — sim only.

Hard-coded, no runtime opt-out. HW uses push_ros_namespace, sim uses URDF <remapping> for the controller_manager surface — see Namespacing and multirobot. Enforced by test_namespace_isolation.py.

Available Nodes

🤖	🖥️	NODE	DESCRIPTION
✅	✅	controller_manager	Controller Manager performs two main functions. First, it manages controllers and their required interfaces, handling tasks like loading, activating, deactivating, and unloading. Second, it interacts with hardware components, ensuring access to their interfaces. controller_manager/controller_manager
✅	✅	drive_controller	The controller managing a mobile robot with a differential or omni drive (mecanum wheels). Converts speed commands for the robot body to wheel commands for the base. It also calculates odometry based on hardware feedback and shares it.DiffDriveController or MecanumDriveController diff_drive_controller/diff_drive_controller
✅	✅	ekf_node	Used to fuse wheel odometry and IMU data. Parameters are defined in rosbot_bringup/config/ekf.yaml robot_localization/ekf_node
❌	✅	/gz_bridge	Transmits Gazebo simulation data to the ROS layer ros_gz_bridge/parameter_bridge
❌	✅	gz_ros_control	Responsible for integrating the ros2_control controller architecture with the Gazebo simulator. gz_ros2_control/gz_ros2_control
✅	✅	imu_broadcaster	The broadcaster to publish readings of IMU sensors imu_sensor_broadcaster/imu_sensor_broadcaster
✅	❌	imu_sensor_node	The node responsible for subscriptions to IMU data from the hardware rosbot_hardware_interfaces/rosbot_imu_sensor
✅	✅	joint_state_broadcaster	The broadcaster reads all state interfaces and reports them on specific topics joint_state_broadcaster/joint_state_broadcaster
✅	✅	robot_state_publisher	Uses the URDF specified by the parameter robot*description and the joint positions from the topic joint*states to calculate the forward kinematics of the robot and publish the results using tf robot_state_publisher/robot_state_publisher
✅	❌	rosbot_system_node	The node communicating with the hardware responsible for receiving and sending data related to engine control rosbot_hardware_interfaces/rosbot_system
❌	✅	rosbot_gz_bridge	Transmits data about the robot between the Gazebo simulator and ROS. ros_gz_bridge/parameter_bridge
✅	❌	rosbot_mcu	Microcontroller unit (MCU) communication node. Default: rosbot_mavlink_bridge (MAVLink). With backend:=microros it is replaced by the micro_ros_agent node, which speaks XRCE-DDS to the MCU instead. [rosbot_mavlink_bridge/rosbot_mavlink_bridge]

Available Topics

🤖	🖥️	TOPIC	DESCRIPTION
✅	✅	cmd_vel	Sends velocity commands for controlling robot motion. geometry_msgs/Twist
✅	✅	diagnostics	Contains diagnostic information about the robot's systems. diagnostic_msgs/DiagnosticArray
✅	✅	dynamic_joint_states	Publishes information about the dynamic state of joints. control_msgs/DynamicJointState
✅	✅	imu/data	Broadcasts IMU (Inertial Measurement Unit) data. sensor_msgs/Imu
✅	✅	joint_states	Publishes information about the state of robot joints. sensor_msgs/JointState
✅	✅	joy	Publishes joystick input data. sensor_msgs/Joy
✅	✅	odometry/filtered	Publishes filtered odometry data. nav_msgs/Odometry
✅	✅	odometry/wheels	Provides odometry data from the base controller of the ROSbot XL. nav_msgs/Odometry
✅	✅	robot_description	Publishes the robot's description. std_msgs/String
✅	✅	scan	Publishes raw laser scan data. sensor_msgs/LaserScan
✅	✅	set_pose	Changes the robot's odometry/filtered pose. geometry_msgs/PoseWithCovarianceStamped
✅	✅	tf	Publishes transformations between coordinate frames over time. tf2_msgs/TFMessage
✅	✅	tf_static	Publishes static transformations between coordinate frames. tf2_msgs/TFMessage

There are also additional topics related with the ROSbot firmware. For more information about them, please refer to the ROSbot Firmware documentation.

Package Description

rosbot

Metapackage that contains dependencies to other repositories.

rosbot_bringup

The main package responsible for running the physical robot.

Available Launch Files:

• rosbot.yaml - activates all logic related to the ROSbot's movement and processing of sensory data.
• rosbot_xl.yaml - activates all logic related to the ROSbot XL's movement and processing of sensory data.
• mavlink.launch.py - starts the rosbot_mavlink_bridge node. Selected when backend:=mavlink (default). Requires a runtime-switch firmware build on the MCU (the boot handshake's BACKEND: line picks the MAVLink path) and the rosbot_mavlink_bridge package on the ROS overlay.
• microros.launch.py - alternative backend that establishes connection with the hardware using the microROS XRCE-DDS agent. Selected when backend:=microros.

rosbot_controller

ROS2 hardware controller for ROSbot. It manages inputs and outputs data from ROS2 control, forwarding it via ROS topics to be read by microROS. The controller.yaml file loads the robot model defined in rosbot_description along with ROS2 control dependencies from rosbot_hardware_interfaces.

Available Launch Files:

• controller.yaml - starts controllers related to ros2_control responsible for driving, communication with imu and joint_states publications

rosbot_description

URDF model used for both simulation and as a source of transforms on physical robot. It was written to be compatible with ROS Industrial and preconfigured for ROS2 control.

Available Launch Files:

• rosbot.yaml - Load URDF and starts ros2_control hardware interfaces
• rosbot_xl.yaml - Load URDF and starts ros2_control hardware interfaces
• rviz.yaml - Launches the RViz configuration for specified robot model.

Main Description Files:

• rosbot.urdf.xacro - Final configuration of ROSbot.
• rosbot_xl.urdf.xacro - Final configuration of ROSbot XL.

rosbot_gazebo

Launch files for Gazebo working with ROS2 control.

Available Launch Files:

• simulations.yaml - Runs simulations with a defined robot and all sensors on it.
• spawn_robot.yaml - Allow to spawn new robot in already running simulation.

rosbot_localization

A package related to the logic responsible for performing sensor fusion.

Available Launch Files:

• ekf.yaml - Runs ekf filter which fuse wheel odometry with imu data.

rosbot_utils

A package containing auxiliary nodes and utilities for the ROSbot Series.

Available Launch Files:

• battery_alert.yaml - launch the node that plays an audible alert when the battery level drops below a threshold.