2. BRASH Groundsystem BRIDGE Demo

This page will take you through how to run a BRASH bridge that communicates with the cFS TO_Lab and CI_Lab applications.

It uses a number of ROS2 messages that have been automatically generated from cFS binaries, each with a dedicated topic.

This example provides a demonstration on how a ROS2 ecosystem running as part of a mission Ground System could communicate with a flight-side cFS instance.

The basic architecture of this bridge looks like:

BRASH Groundsystem Bridge

2.1. Start cFS

$ cd ~/code/cFS/build/exe/cpu1
$ ./core-cpu1 2>&1 | tee out.txt

2.2. Start the BRASH groundsystem bridge

$ cd ~/code/brash
$ . install/local_setup.bash
$ ros2 launch cfe_plugin cfe_bridge.launch.py

2.3. Use rQT to enable TO messages

  1. In a new terminal start the rQT UI.

    $ ros2 launch brash_application_tools groundsystem_demo.launch.py

  2. Enable TO output by using the Message Publisher plugin to send a command message to the /groundsystem/to_lab_enable_output_cmd topic.

    Enable TO output

    • You will need to expand the payload field in the UI and set the dest_ip the approprate IP, probably '127.0.0.1' unless you have changed it in TO_Lab and CI_Lab.

    • Send the command by right clicking over the message in the Message Publisher window and selecting Publish Selected Once.

    Warning

    The step above is fundamental to get the data flowing to the ground! You’ll see in the terminal running ./core-cpu1 a line showing that the request was received:

    core-cpu1 message showing TO Lab message received

  3. Check and expand the cFE ES Housekeeeping Telemetry topic /groundsystem/cfe_es_hk_tlm in the Topic Monitor window. You should now see telemetry data coming from cFS and translated into a ROS2 message.

View TO output