WEBVTT

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In the next laboratory lesson, we will create our first application and our first package for Ros2.

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So let's clarify the terminology we will use to define all the components and how they interact with

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each other.

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When we installed Ros two, we automatically installed several packages that offer numerous functionalities

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for developing robotics applications.

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Some of these packages are developed directly by the Open Source Robotics Foundation, but there are

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also many others that are developed by independent entities such as universities or innovative companies

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and are offered in an open source format and also are included in the default Ros two installation due

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to their success.

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In addition to these resources that will be very useful throughout the course to speed up the development

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of our robot.

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We will also implement new functionalities, so new packages that will add capabilities to our robot.

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We will implement these software packages.

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So these functionalities inside our folder of our PC that is called workspace.

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The folder where we installed Ros two and saw the standard packages is called Underlay.

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While our workspace where we will develop all the new robot code is called overlay.

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The overlay will have access to all the packages that are provided by the standard installation of Ros2,

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plus all the new software or the new packages that we will be developing during the course and is placed

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in a folder that is called workspace.

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Furthermore, the overlay not only contains all the new packages that are developed for a specific robot,

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for a specific application, but can also include some of the packages that are already available in

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the standard Ros two installation.

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In this case, we can see, for example, that the package that I named Robot Vision with a fictional

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name has been automatically installed with the installation and also it is present within the Ros two

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overlay.

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So within our workspace in this case, since this package exists both in the underlay and in the overlay,

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the version that is used will be the one in the overlay because as the name suggests, the package is

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in the overlay override those in the underlay that have the same name.

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Finally.

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Then, within each package that makes up our workspace, several files can be included that implement

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the action functionalities of the robot or also can be configuration and startup files for all those

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functionalities.