ROS 2 System Modes

This repository explores a system modes concept that is implemented for ROS 2 in these packages:

• system_modes_msgs provides the message types and services for system modes
• system_modes provides a library for system mode inference, a mode manager, and a mode monitor
• system_modes_examples implements a simple example
• launch_system_modes launch actions, events, and event handlers for system modes
• test_launch_system_modes launch test for the launch_system_modes` package

For further information, please contact Arne Nordmann or Ralph Lange.

Purpose of the Project

This software is not ready for production use. It has neither been developed nor tested for a specific use case. However, the license conditions of the applicable Open Source licenses allow you to adapt the software to your needs. Before using it in a safety relevant setting, make sure that the software fulfills your requirements and adjust it according to any applicable safety standards, e.g., ISO 26262.

How to Build, Test, Install, and Use

After you cloned this repository into your ROS 2 workspace folder, you may build and install the system_modes package and the system_modes_examples package using colcon: $ colcon build --packages-select-regex system_modes

Have a look at the system_modes_examples documentation to try your installation.

For using this package and designing system modes for your system, please refer to the How to Apply section.

License

ROS 2 System Modes are open-sourced under the Apache-2.0 license. See the LICENSE file for details.

For a list of other open-source components included in ROS 2 system_modes, see the file 3rd-party-licenses.txt.

Quality assurance

The colcon_test tool is used for quality assurances, which includes cpplint, uncrustify, flake8, xmllint and various other tools.

Unit tests based on gtest are located in the ./system_modes/test folder.

Known Issues/Limitations

Please notice the following issues/limitations:

• Currently, (sub-)systems managed by the mode manager are not recognized by the ros2 lifecycle tool ("Node not found"). So to trigger lifecycle transitions in (sub-)systems, you have to go with the ros2 service call tool. Check the system_modes_examples documentation for example calls.
• The Error Handling and Rules feature is still experimental and might be subject to major changes. However, if no rules are specified in the model file, this feature is not used.
• The mode inference and the error handling and rules feature do not work as intended if some of the involved nodes are non-lifecycle nodes.

Acknowledgments

This activity has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement n° 780785).