MicroDDS Agent/MicroROS

Introduction

The following was user contributed content and edited by NXP. Note that there are several methods available for communication between ROS and PX4. This documents an established method.

Setting up the MicroDDS Agent/MicroROS

One method used to communicate between the NavQPlus and the FMUK66v3 using T1 or Serial is by using MicroROS or the XRCE-dds Agent. To install these tools:

git clone https://github.com/eProsima/Micro-XRCE-DDS-Agent
cd Micro-XRCE-DDS-Agent
mkdir build && cd build
cmake ..
make
sudo make install

If using yocto, you can use the WIP meta package in your recipe.

https://github.com/dirksavage88/meta-dds

Alternatively, you can install micro-ROS through the ubuntu snap store

Install micro-ros-agent on Ubuntu using the Snap Store | SnapcraftSnapcraft

micro-ROS snap package

Another way to get micro-ROS is through Github as a ROS2 package. You can use the colcon build tools after sourcing the ROS setup.bash script in "/opt/ros/galactic/setup.bash"

GitHub - micro-ROS/micro_ros_setup: Support macros for building micro-ROS-based firmware.GitHub

micro-ROS package

colcon build --symlink-install

Follow the instructions for each package on how to run the agent. The agent is a broker for clients on the network (including the FMUK66) and allows topics from the pixhawk to be shared with the DDS global space.

To set up the NavQ+, follow instructions in the Setup Guide -eMMC for a static IP. The FMUK66 is IP "10.0.0.1". As an example, you can set the NavQ+ to "10.0.0.3" with a blank ipv4.gateway (no quotes or anything) on Wired Connection 1.

Then start the microdds agent that is installed in the home directory in the Micro-XRCE-DDS-Agent build folder.

./MicroXRCEAgent udp4 -p 2019

On the FMUK66, ensure you have flashed to main and enter the following command.

microdds_client start -t udp -h 10.0.0.3 -p 2019

You should see the topic listed in the mavlink console after running the client start, as well as topic, publishers, data writers, and creators on the agent side.