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Add a custom ROS message#


During the Autoware development, you will probably need to define your own messages. Read the following instructions before adding a custom message.

  1. Message in autoware_msgs define interfaces of Autoware Core.

    • If a contributor wishes to make changes or add new messages to autoware_msgs, they should first create a new discussion post under the Design category.
  2. Any other minor or proposal messages used for internal communication within a component(such as planning) should be defined in another repository.

The following is a simple tutorial of adding a message package to autoware_msgs. For the general ROS 2 tutorial, see Create custom msg and srv files.

How to create custom message#

Make sure you are in the Autoware workspace, and then run the following command to create a new package. As an example, let's create a package to define sensor messages.

  1. Create a package

    cd ./src/core/autoware_msgs
    ros2 pkg create --build-type ament_cmake autoware_sensing_msgs
  2. Create custom messages

    You should create .msg files and place them in the msg directory.

    NOTE: The initial letters of the .msg and .srv files must be capitalized.

    As an example, let's make .msg files GnssInsOrientation.msg and GnssInsOrientationStamped.msg to define GNSS/INS orientation messages:

    mkdir msg
    cd msg
    touch GnssInsOrientation.msg
    touch GnssInsOrientationStamped.msg

    Edit GnssInsOrientation.msg with your editor to be the following content:

    geometry_msgs/Quaternion orientation
    float32 rmse_rotation_x
    float32 rmse_rotation_y
    float32 rmse_rotation_z

    In this case, the custom message uses a message from another message package geometry_msgs/Quaternion.

    Edit GnssInsOrientationStamped.msg with your editor to be the following content:

    std_msgs/Header header
    GnssInsOrientation orientation

    In this case, the custom message uses a message from another message package std_msgs/Header.

  3. Edit CMakeLists.txt

    In order to use this custom message in C++ or Python languages, we need to add the following lines to CMakeList.txt:


    💬 The ament_cmake_auto tool is very useful and is more widely used in Autoware, so we recommend using ament_cmake_auto instead of ament_cmake.

    We need to replace

    find_package(ament_cmake REQUIRED)


    find_package(ament_cmake_auto REQUIRED)
  4. Edit package.xml

    We need to declare relevant dependencies in package.xml. For the above example we need to add the following content:


    We need to replace <buildtool_depend>ament_cmake</buildtool_depend> with <buildtool_depend>ament_cmake_auto</buildtool_depend> in the package.xml file.

  5. Build the custom message package

    You can build the package in the root of your workspace, for example by running the following command:

    colcon build --packages-select autoware_sensing_msgs

    Now the GnssInsOrientationStamped message will be discoverable by other packages in Autoware.

How to use custom messages in Autoware#

You can use the custom messages in Autoware by following these steps:

  • Add dependency in package.xml.
    • For example, <depend>autoware_sensing_msgs</depend>.
  • Include the .hpp file of the relevant message in the code.
    • For example, #include <autoware_sensing_msgs/msg/gnss_ins_orientation_stamped.hpp>.