paho-mqtt + ROS2 Humble

Install ROS2 Humble See ROS2 Humble Installation

mkdir /opt/ros/mqtt_ws/src
cd /opt/ros/mqtt_ws/src
https://github.com/siderdax/ROS2_MQTT_PubSub.git
cd ../
colcon build --symlink-install

source /opt/ros/mqtt_ws/install/setup.bash

ros2 run ros_mqtt publisher

ros2 run ros_mqtt publisher

See Remapping

ros2 run ros_mqtt <publisher/subscriber> --ros-args -r <mqtt_pub_message/mqtt_sub_message>:=<new_topic_name>

Setup MQTT is available with ROS2 parameters

1. MQTT hostname

   ros2 run ros_mqtt <publisher/subscriber> --ros-args -p mqtt_config.host:=<new_address>
   

2. MQTT port

   ros2 run ros_mqtt <publisher/subscriber> --ros-args -p mqtt_config.port:=<new_tcpip_port>
   

3. MQTT topic

   ros2 run ros_mqtt <publisher/subscriber> --ros-args -p mqtt_config.topic:=<new_mqtt_topic_name>
   

4. With paramter file
   1. Create parameter file "params.yaml" and write below

      /mqtt_sub:
      ros__parameters:
          mqtt_config:
          host: 127.0.0.1
          port: 1883
          topic: ros_mqtt_sub
      
      /mqtt_pub:
      ros__parameters:
          mqtt_config:
          host: 127.0.0.1
          port: 1883
          topic: ros_mqtt_pub
      

   2. Run node

      ros2 run ros_mqtt <publisher/subscriber> --ros-args --params-file params.yaml
      

5. launch file (launch files are exist in the ros_mqtt/share)
   • subscriber

     ros2 launch ros_mqtt subscriber.launch.py host:=<address> port:=<port> topic:=<topic>
     

   • publisher

     ros2 launch ros_mqtt publisher.launch.py host:=<address> port:=<port> topic:=<topic>