Control Launch Files#

Overview#

The Autoware control stacks start launching at autoware_launch.xml as mentioned on the Launch Autoware page. The autoware_launch package includes tier4_control_component.launch.xml for initiating control launch files invocation from autoware_launch.xml. The diagram below illustrates the flow of Autoware control launch files within the autoware_launch and autoware.universe packages.

control-launch-flow — Autoware control launch flow diagram

Note

The Autoware project is a large project. Therefore, as we manage the Autoware project, we utilize specific arguments in the launch files. ROS 2 offers an argument-overriding feature for these launch files. Please refer to the official ROS 2 launch documentation for further information. For instance, if we define an argument at the top-level launch, it will override the value on lower-level launches.

tier4_control_component.launch.xml#

The tier4_control_component.launch.xml launch file is the main control component launch in the autoware_launch package. This launch file calls control.launch.xml from the tier4_control_launch package within the autoware.universe repository. We can modify control launch arguments in tier4_control_component.launch.xml. Additionally, we can add any other necessary arguments that need adjustment since tier4_control_component.launch.xml serves as the top-level launch file for other control launch files. Here are some predefined control launch arguments:

lateral_controller_mode: This argument determines the lateral controller algorithm. The default value is mpc. To change it to pure pursuit, make the following update in your tier4_control_component.launch.xml file:
```
- <arg name="lateral_controller_mode" default="mpc"/>
+ <arg name="lateral_controller_mode" default="pure_pursuit"/>
```

enable_autonomous_emergency_braking: This argument enables autonomous emergency braking under specific conditions. Please refer to the Autonomous emergency braking (AEB) page for more information. To enable it, update the value in the tier4_control_component.launch.xml file:
```
- <arg name="enable_autonomous_emergency_braking" default="false"/>
+ <arg name="enable_autonomous_emergency_braking" default="true"/>
```

enable_predicted_path_checker: This argument enables the predicted path checker module. Please refer to the Predicted Path Checker page for more information. To enable it, update the value in the tier4_control_component.launch.xml file:
```
- <arg name="enable_predicted_path_checker" default="false"/>
+ <arg name="enable_predicted_path_checker" default="true"/>
```

Note

You can also use this arguments as command line arguments:

ros2 launch autoware_launch autoware.launch.xml ... enable_predicted_path_checker:=true lateral_controller_mode:=pure_pursuit ...

The predefined arguments in tier4_control_component.launch.xml have been explained above. However, numerous control arguments are included in the autoware_launch control config parameters.