Robot State Publisher

This package contains the Robot State Publisher, a node and a class to publish the state of a robot to tf2. At startup time, Robot State Publisher is supplied with a kinematic tree model (URDF) of the robot. It then subscribes to the joint_states topic (of type sensor_msgs/msg/JointState) to get individual joint states. These joint states are used to update the kinematic tree model, and the resulting 3D poses are then published to tf2.

Robot State Publisher deals with two different "classes" of joint types: fixed and movable. Fixed joints (with the type "fixed") are published to the transient_local /tf_static topic once on startup (transient_local topics keep a history of what they published, so a later subscription can always get the latest state of the world). Movable joints are published to the regular /tf topic any time the appropriate joint is updated in the joint_states message.

Examples showing how to pass the robot_description parameter using a launch file are available in the 'launch' subdirectory.

Published Topics

• robot_description (std_msgs/msg/String) - The description of the robot URDF as a string. Republishes the value set in the robot_description parameter, which is useful for getting informed of dynamic changes to the URDF. Published using the "transient local" quality of service, so subscribers should also be "transient local".
• tf (tf2_msgs/msg/TFMessage) - The transforms corresponding to the movable joints of the robot.
• tf_static (tf2_msgs/msg/TFMessage) - The transforms corresponding to the static joints of the robot.

Subscribed Topics

• joint_states (sensor_msgs/msg/JointState) - The joint state updates to the robot poses. The RobotStatePublisher class takes these updates, does transformations (such as mimic joints), and then publishes the results on the tf2 topics.

Parameters

• robot_description (string) - The original description of the robot in URDF form. This must be set at robot_state_publisher startup time, or the node will fail to start. Updates to this parameter will be reflected in the robot_description topic.
• publish_frequency (double) - The maximum frequency at which non-static transforms (e.g. joint states) will be published to /tf. Defaults to 20.0 Hz.
• ignore_timestamp (bool) - Whether to accept all joint states no matter what the timestamp (true), or to only publish joint state updates if they are newer than the last publish_frequency (false). Defaults to false.
• frame_prefix (string) - An arbitrary prefix to add to the published tf2 frames. Defaults to the empty string.

Changelog for package robot_state_publisher

3.3.1 (2023-06-07)

• Improve log messages (#206)
• Contributors: Nick Lamprianidis

3.3.0 (2023-04-28)

3.2.0 (2023-04-11)

• Update robot_state_publisher to C++17. (#204)
• Contributors: Chris Lalancette

3.1.2 (2023-02-13)

• [rolling] Update maintainers - 2022-11-07 (#203)
• Contributors: Audrow Nash

3.1.1 (2022-09-13)

• Mirror rolling to ros2
• Contributors: Audrow Nash

3.1.0 (2022-05-10)

3.0.2 (2022-04-05)

• Depend on orocos_kdl_vendor (#191)
• Contributors: Jacob Perron

3.0.1 (2022-03-28)

• export dependencies, to use robot_state_publisher as a component (#193)
• Contributors: Kenji Brameld

3.0.0 (2022-01-14)

• Fix include order for cpplint (#186)
• Change how parameter updates are handled (#180)
• Install includes to instal/\${PROJECT_NAME} (#184)
• Make the change_fixed_joint test more robust (#183)
• Add in a test to make sure fixed transforms change on update
• Small C++ nice-isms in the tests
• Switch to using target_include_directories for tests
• Publish new fixed transforms when URDF is updated
• Make joint_states subscription QoS configurable; default to SensorDataQoS (#179)
• Remove dependency on urdfdom_headers (#168)
• Contributors: Anthony Deschamps, Chris Lalancette, Jacob Perron, Russell Joyce, Shane Loretz

2.7.0 (2021-10-18)

• Fix deprecated subscriber callbacks (#173)
• Contributors: Abrar Rahman Protyasha

2.6.0 (2021-08-02)

• Cleanup the documentation in the RobotStatePublisher class. (#172)
• Always publish fixed frames to /tf_static (#158)
• corrected publish_frequency default in README (#166)
• Contributors: Chris Lalancette, Jacob Perron, Nils Schulte

2.5.0 (2021-06-11)

• Add tf frame_prefix parameter (#159)
• Contributors: Steve Nogar, Chris Lalancette

2.4.3 (2021-04-19)

• Stop rejecting unknown parameters. (#161)
• Contributors: Chris Lalancette

2.4.2 (2021-01-25)

• clean up license to be standard bsd 3 clause (#130)
• Update the maintainers. (#151)
• Contributors: Chris Lalancette, Tully Foote

2.4.1 (2020-09-28)

• fix types in range loops to avoid copy due to different type (#143)
• Make sure not to crash on an invalid URDF. (#141)
• Contributors: Chris Lalancette, Dirk Thomas

2.4.0 (2020-04-30)

• Replace deprecated launch_ros usage (#137)
• code style only: wrap after open parenthesis if not in one line (#129)
• Refactor the ROS 2 code to be more modern (#126)
• Switch to using TARGET_FILE to find the binary targets on Windows.
• Fix tests on Windows.
• Make the error message much nicer on Windows.
• robot_state_publisher_node -> robot_state_publisher
• Fix test build on Windows.
• Get rid of redundant declaration.
• Guard against negative publish_frequencies.
• Switch to modern launch_testing ReadyToTest.
• Add testing to robot_state_publisher.
• Update some example launch files.
• Implement the ability to change the parameters on the fly.
• Fix silly bug while computing the publish interval.
• Refactor to have a \"setup\" function during the constructor and later on during the parameter setup.
• Mark things as explicit and final.
• Update the documentation.
• Make robot_state_publisher composable.
• Contributors: Chris Lalancette, Dirk Thomas, Jacob Perron

2.3.1 (2019-10-23)

• Switch the license back to BSD. (#121)
• Contributors: Chris Lalancette

2.3.0 (2019-09-26)

• Install include directories (#31)
• Publish URDF string on startup (#24)
• Contributors: Patrick Beeson, Poh Zhi-Ee, Shane Loretz

2.2.4 (2019-09-06)

• Remove unused Eigen3 dependency (#27) (#29)
• Don\'t export exe as library (#25) (ros2 #28)
• Contributors: Shane Loretz

2.2.3 (2019-06-12)

• Use rclcpp::Time for stamping transforms (#20)
• Contributors: Scott K Logan

2.2.2 (2019-05-08)

• changes to avoid deprecated API\'s (#19)
• Contributors: William Woodall

2.2.1 (2019-04-26)

• Updated to avoid deprecated API. (#18)
• Contributors: William Woodall

2.2.0 (2019-04-14)

• Set urdf content as parameter. (#15)
• Contributors: Karsten Knese

2.1.0 (2018-06-27)

• The robot model is now published on the robot_description topic as a std_msgs/String.msg. (#9)
• Contributors: Brett, Mikael Arguedas

1.13.4 (2017-01-05)

• Use urdf::*ShredPtr instead of boost::shared_ptr (#60)
• Error log for empty JointState.position was downgraded to a throttled warning (#64)
• Contributors: Jochen Sprickerhof, S