ReBeL EduMove ROS Package Documentation

General Architecture

The control architecture of the EduMove system is modular and based on a combination of embedded computing, network communication, and the ROS2 framework.

ROS2 EduMove Package

The ROS2 EduMove Package utilizes the following components:

• Gazebo Sim: For simulation purposes.
• RViz: For visualizing robot state, sensor data, and navigation results.
• EduMove Controllers: For controlling the EduMove platform and ReBeL arm.
• Movelt2: For motion planning.
• Nav2: For autonomous navigation, path planning, and collision avoidance.
• ROS2: The core middleware.
• Lidar SLAM: For localization and mapping using the RPLidar A2M12.
• Lidar-Stream: Data stream from the lidar.
• USB-Port: Connects the lidar to the ROS environment.
• Robot Control: Interface for controlling the robot.
• Ethernet: Network communication.
• EDU (Omni-Move): The EduMove platform itself.

The connection between the control system and EduMove is currently established via Ethernet. Information from the lidar sensor is transmitted to the ROS environment via the USB port.

The following key components are summarized:

• Visualisierung: RViz2 is used to visualize robot state, sensor data, and navigation results.
• Simulation: Gazebo is used as the simulation environment to model the platform and the robotic arm and to perform tests.
• Navigation: For localization and mapping, the RPLidar A2M12 is used in combination with a SLAM-Algorithmus. The Nav2-Stack is implemented for autonomous navigation, handling path planning and collision avoidance.

Workspace Architecture ROS

The packages in the ROS workspace are located in the /src folder. There are five packages:

src

• edumove_bringup
• edumove_controllers
• edumove_description
• edumove_moveit_config
• hardware_drivers

edumove_bringup

• All configuration files for the workspace are stored under config, divided into software and hardware.
• All launch files are included in this package, also divided into software and hardware.
• Pre-generated maps are stored under maps.
• An automated script for map saving is located under scripts.

edumove_controllers

• Hybrid interface for controlling the edumove platform and ReBeL-arm.

edumove_description

• Contains meshes and URDF files for the ReBeL arm and the mobile platform.

edumove_moveit_config

• Configuration package for using Movelt, customized for the EduMove system.

hardware_drivers

• Repo RPLidar A2M12

How to start for the first time

The software solution can be run on a computer with ROS Jazzy installed, or in a Docker environment. Both options are also described in a README file within the ROS workspace (located in the project folder).

Hint:

• For more information for using Nav2 see Nav2 doc.
• For more information for using Movelt2 see Movelt2 doc.

With Docker

Execute the following commands in a terminal started from the project folder:

1. Build the docker image for the first time:
   sudo docker compose up --build
2. If the image has been already built, just run:
   sudo docker compose up
3. Whenever opening a new terminal, access the docker container environment:
   sudo docker exec -it ros2_jazzy_edumove_dev bash

Without Docker

Execute the following commands in a terminal started from the project folder.

Attention: Make sure that all required packages and libraries are installed on your device (this depends on how you installed ROS). The packages can be found in the package.xml files of the ROS packages within the workspace.

For installing with rosdep (in case you not already installed rosdep):

1. Install rosdep:
   apt-get install python3-rosdep
2. Install dependencies:
   sudo rosdep init
rosdep update
rosdep install --from-paths src -y --ignore-src

With the dependencies installed, you can build your workspace:

Build the code directly in the project folder:
colcon build

How to start mapping

Do not forget to source the ROS workspace before launching.

1. Launch the main program:
   ros2 launch edumove_bringup bringup.launch.py use_gui:='true' mode:='mapping'
2. Drive the platform using teleop_twist_keyboard:
   ros2 run teleop_twist_keyboard teleop_twist_keyboard --ros-args --remap cmd_vel:=cmd_vel/joy
3. Save map:
   ros2 run edumove_bringup custom_map_saver.py --ros-args -p map_name:=edumove_map

A map is created as a pgm file, and a yaml file references it. The map looks as follows:

[Map visualization of the environment]

How to start navigation program

Do not forget to source the ROS workspace before launching.

1. Launch the main program:
   ros2 launch edumove_bringup bringup.launch.py use_gui:='true' mode:='localization' map_name:='edumove_map'

You should replace edumove_map by your own map.

• Set an initial pose on rviz
• Set goal on rviz

The initial position must be set via the RViz interface after startup. To do this, click the following button in the top toolbar: [2D Pose Estimate button]

After that, click (and hold) on the map at the estimated position where EduMove is located, then drag in the direction EduMove is oriented, represented by the green arrow.

Setting a target position works in the same way. First, select 2D Goal Pose, then click on a point on the map and drag to set the desired target orientation. After this, the planning process within Nav2 begins.