ros2_simple package

Simple ROS2 package containing basic nodes fthat can be used as example and/or to test the new environment. It contains:

• a publisher node that updates the position of a marker (cube) shifting it to x-coordinate of a certain amount.
• a subscriber node that subscribes to the marker topic and displays the elaspled time between messages.

Topics

Topic name: /marker_topic.
Message type: visualization_msgs::msg::Marker.

Parameters

Parameters are configurable in /config/params.yaml.

• publisher_frequency: frequency of marker position update [Hz].
• speed: speed of the marker [m/s]. This is used with the frequency to compute the shift to apply to the new marker message.

How to use

Quick instructions how to use the package.

Build the package

Clone the package inside the src directory of your ros2 workspace. From the workspace directory run:

colcon build --packages-select ros2_simple

Run Publisher

To run the MarkerPublisher node with default parameters, use the command:

ros2 run ros2_simple marker_pub_node

To run the MarkerPublisher node loading custom parameters from a params.yaml, file use the command:

ros2 run ros2_simple marker_pub_node --ros-args --params-file /path/to/params.yaml

If you run the command from your workspace directory, the path would be src/ros2_simple/config/params.yaml.

Run Subscriber

To run the MarkerSubscriber node, use the command:

ros2 run ros2_simple marker_sub_node

Run via launch file

A launch file is available in the directoty /config inside ros2_simple package. This file will launch both MarkerPublisher and MarkerSubscriber nodes and it will load the params.yaml file, i.e. the custom parameters.
To launch the whole package use the command:

ros2 launch ros2_simple marker_launch.py

Testing

To be developed..