ROS 2 Migration¶

Quad-SDK now targets ROS 2 Jazzy on Ubuntu 24.04. This page captures what changed, why, and what to update if you're porting downstream code from a ROS 1 fork.

Looking for ROS 1 docs?

Use the version selector in the top-right of this site to switch to the ros1 docs. The ROS 1 stack is no longer actively developed — we recommend new work targets ROS 2.

What changed at a glance¶

Area	ROS 1	ROS 2 (current)
Build system	`catkin` / `catkin_make`	`colcon` + `ament_cmake` / `ament_python`
Launch	XML `*.launch`	Python `*.py` (Launch description API)
Node API	`roscpp` / `rospy`	`rclcpp` / `rclpy`
Time	`ros::Time::now()`	`node->now()` (clock-aware)
Params	`<param>` in launch	`ros__parameters` YAML, namespace wildcards
Kinematics/dynamics	RBDL (`QuadKD`)	Pinocchio (`QuadKD2`)
Simulation	Gazebo Classic	Gazebo Harmonic (`gz sim`) + MuJoCo
ROS bridge for Gazebo	`gazebo_ros`	`ros_gz_bridge`
Robot description	URDF + xacro	URDF + xacro + SDF (Gazebo)
Bag format	`.bag`	rosbag2 (mcap by default)

What you need to update if porting¶

Launch files¶

ROS 1:

<launch>
  <include file="$(find quad_utils)/launch/planning.launch"/>
  <node pkg="local_planner" type="local_planner_node" name="local_planner"/>
</launch>

ROS 2 equivalent:

from launch import LaunchDescription
from launch.actions import IncludeLaunchDescription
from launch_ros.actions import Node
from launch_ros.substitutions import FindPackageShare

def generate_launch_description():
    return LaunchDescription([
        IncludeLaunchDescription(
            FindPackageShare("quad_utils").find("planning.py"),
        ),
        Node(package="local_planner", executable="local_planner_node"),
    ])

See quad_utils/launch/ for canonical examples — favor OpaqueFunction and FindPackageShare.

Parameter loading¶

Drop <param> and <rosparam>. Put per-robot params in quad_utils/config/<robot>.yaml:

/**:
  ros__parameters:
    local_planner:
      update_rate: 333.0
      timestep: 0.03

Namespace-wildcard nodes (/**:) make params apply across the multi-robot tree.

Topic API¶

ROS 1 → ROS 2 cheat sheet for the bits that bite:

// Publisher
auto pub = node->create_publisher<quad_msgs::msg::RobotPlan>("global_plan", 10);

// Subscription
auto sub = node->create_subscription<quad_msgs::msg::RobotState>(
    "state/ground_truth", 10,
    [this](const quad_msgs::msg::RobotState::SharedPtr msg) { /* ... */ });

// Timer
auto t = node->create_wall_timer(33ms, [this]() { update(); });

Time¶

ros::Time::now() → node->now(). Always pass the node's clock (or use rclcpp::Clock) — never wallclock — so sim-time and bag playback work.

Kinematics¶

If your code calls QuadKD::*FK*(), the same call is generally available on QuadKD2, but build a Pinocchio::Model from the URDF once and call updateFromPinocchio() per control loop before any FK/Jacobian evaluation. Joint ordering follows URDF order; use the supplied mappers when crossing the API boundary. See Pinocchio integration.

Bags¶

.bag → rosbag2 (mcap). Replay:

ros2 bag play <bag_directory>

For MATLAB post-processing, regenerate Quad-SDK message bindings once:

ros2genmsg('~/ros2_ws/src/quad-sdk')
rehash toolboxcache; clear

Tests¶

catkin_add_gtest → ament_add_gtest. See quad_utils/test/ for templates.

What didn't change¶

Topic names (global_plan, local_plan, state/ground_truth, etc.)
Message structure (quad_msgs::* are unchanged in shape, only the namespace path is quad_msgs::msg::* in ROS 2)
High-level architecture, the planning/control split, and the runtime loop rates
The per-package config scheme — same YAML keys, just under ros__parameters

Removed in the ROS 2 build¶

ROS 1 launch XML files
RBDL build path (the source files remain in-tree but are not linked)
Gazebo Classic worlds (replaced with Gazebo Harmonic SDF + MuJoCo MJCF)

The legacy underbrush controller is still available in the ROS 2 build, but it currently only runs on the Ghost Robotics Spirit 40 — see Specialized Controllers for usage and porting notes.

Pinocchio integration