Getting started

In this section you will find information about the software and tools we will use during the course and how to install them and how to set everything up.

Integrated Development Environment (IDE)

What is an IDE?

An IDE is a software application that provides facilities for software development, like a source code editor, build automation, debugger, syntax highlighting, auto completion etc.

Which IDE do we use?

For Introduction to Robotics we suggest using the free to use IDE Visual Studio Code from Microsoft. Detailed installation instructions based on your OS and links to download the installer can be found under the following links:

• Windows
• Linux
• macOS

In the following subsection we introduce you to the user interface and give a general introduction on how to use VS Code. If you are already familiar with VS Code feel free to skip the following subsection.

Getting Started with VS Code

Once the installation worked successfully open VS Code. The graphical user interface (GUI) opens up and should look similar to the following image.

Visual Studio Code starting window.

To get an orientation on how to use and navigate in VS Code we recommend you watching the Getting Started Video out of the introductory video series from the VS Code website.

Recommended Extensions for VS Code

The following extensions will be helpful for the upcoming work during the course. In the brackets next to the general name the identifier is stated, which makes it easier to search for the correct extension. Information how to install an extension in VS Code can be found in the video mentioned in the section above.

• Python (ms-python.python)
• Pylance (ms-python.vscode-pylance)
• Docker (ms-azuretools.vscode-docker)
• C/C++ Extension Pack (ms-vscode.cpptools-extension-pack)

Docker

What is Docker?

Docker is a software tool that allows developers to package their applications into portable and self-sufficient containers.

Think of it like a shipping container that can hold all the necessary components of an application:

• operating system,
• libraries,
• dependencies and
• code.

This container can then be moved between different environments, such as from a developer's laptop to co-workers laptops or to a server in the cloud, without needing to worry about the underlying infrastructure.

In our case, it will help us to ensure we are all working in the same environment, regardless of your personal machines.

A Docker container is a running instance of a Docker image. It is a standalone executable package that includes everything needed to run the application. Docker container run isolated from the host system and other containers.

A Docker image is a snapshot of an application or system that has been packaged with all the necessary dependencies and configurations required to run and work for a desired use case. It can be thought of a template or a blueprint for creating a Docker container.

In Introduction to Robotics we will provide you a Docker image that is a snapshot of an Ubunutu operating system with the Robot Operating System (ROS) installed and all the necessary additional libraries that will be necessary for this course.

In the following sections you will find information on how to install Docker and how to start a running Docker container as an instance of the Docker image we provided for this course.

Installing Docker

Comprehensive instructions on how to install Docker Desktop on your machines operating system can be found here.

After successfull installation, open Docker Desktop. The GUI should open as shown in the following screenshot.

Docker Desktop starting window

Starting a Container to work with ROS

To make sure you can all start with the same working ROS environment we use a predefined image and compose file. Both are stored in this repository at 00_GettingStarted/docker/i2r/.

Follow the instructions to download the repository to your local machine and start the group of containers:

1. Create a folder named i2r for the contents of the Introduction to Robotics course.

2. Open this folder in VS Code by either starting VS Code from Terminal or by using the GUI.

   • Using GUI:

     • Open VS Code.
     • Go to File → Open Folder and select in the upcoming window the folder your_local_path/i2r/

   • Terminal (Linux, macOS):

     cd <your local path>/i2r/

     code .

   • Powershell (Windows)

     cd <your local path>\i2r\

     code .

3. Open the Terminal in VS Code (Terminal → New Terminal). The path in the Terminal should be the one you selected before.

4. Now clone the repository from gitlab by copying the follwing command into the Terminal and press enter. (You are asked to enter your gitlab user name and password.)

   git clone https://git.rwth-aachen.de/introduction-to-robotics-course/introduction-to-robotics-2023.git

   • If you don't have git installed, you can either install it or go to the gitlab repository using the browser and download the source code into the i2r folder.
     • Information on how to install git can be found for all OS here

5. Now that all the files from the repository are on your local machine, change in the terminal to the folder where the docker-compose.yml file is stored.

   cd introduction-to-robotics-2023/00_GettingStarted/docker/i2r/

6. Run the following command to spin up the scenario that is defined in the docker-compose.yml file. To be able to use all commands starting with docker, Docker Desktop has to run in the background.

   docker compose up

   This command will download the needed images and start two containers. One container named i2r-ros-1 which contains a snapshot of an Ubuntu OS with ROS and additional packages installed. The second container is an auxiliary container named i2r-gui-1 that will be used to inspect graphical user interfaces of applications started in the i2r-ros-1 container.

   The terminal output will look the following:

   

7. In the Docker Desktop GUI go to the Containers tab. You should see now, that there are two containers launched under the group name i2r.

   Docker Desktop GUI: Inside the Containers tab you should find the started group of containers.

   • Another option to inspect the containers is using the terminal. (Note: If you are still in the terminal you executed the docker compose up, make sure to start a new terminal, but let the old terminal running.)

     docker ps --all

     The terminal output will look the following:

     

     There will be information like ID of the container, name of the image the container was build from etc.

8. To connect to the i2r-ros-1 container, the container we will use to work with ROS, execute the following command from terminal:

   docker exec -it i2r-ros-1 bash

   

   This starts a bash session in the running i2r-ros-1 container. Bash (Bourne-again shell) is a Unix-shell that interacts as a human-machine interface with an environment to allow line by line text in- and output.

9. Now you can test if the i2r-ros-1 container you started has ROS installed and working, by launching roscore. The ROS specific terminal command roscore launches a collection of nodes that are essential to work with a ROS-based system. You will learn more about the basics of ROS in the Introduction to ROS chapter.

   roscore

   

   If that worked out, you can close the started ROS Master by typing Ctrl + C. That shuts down the Master node. To leave the bash session inside of the i2r-ros-1 container just type Ctrl + D.

   

10. To stop the started group of containers named i2r you can either use the Docker Desktop GUI from the Container tab like shown below.

    

    Or switch again to the terminal, where you run the docker compose up command and press Ctrl + C.

    

    Another option, if that terminal is already closed, is to use the following command:

    docker stop i2r-ros-1 i2r-gui-1

11. If all the previous steps worked you have successfully installed the envrionment we will be using during in Introduction to Robotics course to work with ROS.

    If you want to restart a container just make sure that:

    • Docker Desktop is running and
    • start the group of containers named i2r by using ...

      • GUI or

        

      • Terminal

        docker start i2r-ros-1 i2r-gui-1

        

In case of problems

If you run into any issues during the installation process of these softwares, you are welcome to ask me (Contact Data, via mail, phone or in presence).