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Guidelines and Best Practices
Controllers for Mobile Robots
Controllers for Manipulators and Other Robots
The controllers are using common hardware interface definitions, and may use namespaces depending on the following command interface types:
Broadcasters are used to publish sensor data from hardware components to ROS topics. In the sense of ros2_control, broadcasters are still controllers using the same controller interface as the other controllers above.
Common Controller Parameters
Every controller and broadcaster has a few common parameters. They are optional, but if needed they have to be set before
onConfigure transition to
inactive state, see lifecycle documents. Once the controllers are already loaded, this transition is done using the service
configure_controller of the controller_manager.
update_rate: An unsigned integer parameter representing the rate at which every controller/broadcaster runs its update cycle. When unspecified, they run at the same frequency as the controller_manager.
is_async: A boolean parameter that is needed to specify if the controller update needs to run asynchronously.