Bring-Up

launch files for the whole system

Launch File Naming

Each launch file is prefixed either with a category or a competition name:

• main_gs.launch.py: main ground station setup
• urc_pc_nav.launch.py: URC onboard PC setup for the navigation mission
• util_compasscal.launch.py: compass calibration utility

In case of competition launches, that prefix (competition name) is followed by the deployment type:

• urc_gs_...: ground station laptop
• urc_pc_...: onboard PC
• urc_arm_...: arm RPi
• urc_sim_...: simulated rover and station on the developer’s PC

Then there’s the name of the mission that the launch file is for:

• urc_gs_nav: navigation mission
• urc_gs_sci: science mission …

And then, other details may follow:

• urc_sim_nav_base: the base setup for the simulation of URC navigation mission, without the navigation stack
• urc_sim_nav_stack: navigation stack, restarted separately from the base setup to accelerate development

gen_launch()

Each launch file uses the kalman_bringup.gen_launch() helper to start up different subsystems.

This function takes in a blueprint dict that tells it which modules to start and how to configure them. It allows us to quickly create launch files with custom configurations while maintaining their readability.

Example Compass Calibration launch:

from kalman_bringup import *

def generate_launch_description():
    return gen_launch({
        "hardware": {
            "master": "pc",
            "compass_calibration": "30.0",
        },
        "wheels": {},
    })

…which is equivalent to the following commands run in separate shells:

ros2 launch kalman_hardware hardware.launch.py master:=pc compass_calibration:=30.0
ros2 launch kalman_wheels wheels.launch.py