Restructuring ROS 2 Gem docs (o3de#2266)

* First step towards the new structure. Some information updated

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>

* restructuring, update

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>

* added api reference link

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>

* Applied review comments.

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>

* Adjusted inactive links.

Signed-off-by: Michał Pełka <michal.pelka@robotec.ai>

* Commented out in-progress sections.

Signed-off-by: Michał Pełka <michal.pelka@robotec.ai>

* Apply suggestions from code review

Co-authored-by: Wojtek <125894910+wojtek-robotecai@users.noreply.github.com>
Signed-off-by: Michał Pełka <michalpelka@gmail.com>

* Further adjustments to review.

Signed-off-by: Michał Pełka <michal.pelka@robotec.ai>

* Adjusted to the review.

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>

Co-authored by: Channele Mosquera <chanmosq@amazon.com>

* added class diagram link

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>

---------

Signed-off-by: Adam Dabrowski <adam.dabrowski@robotec.ai>
Signed-off-by: Michał Pełka <michal.pelka@robotec.ai>
Signed-off-by: Michał Pełka <michalpelka@gmail.com>
Co-authored-by: Michał Pełka <michal.pelka@robotec.ai>
Co-authored-by: Michał Pełka <michalpelka@gmail.com>
Co-authored-by: Wojtek <125894910+wojtek-robotecai@users.noreply.github.com>

content/docs/user-guide/gems/reference/_index.md

@@ -155,7 +155,7 @@ toc: true
 
 | Gem | Description |
 | - | - |
-| [ROS 2](./ros2/) | The ROS 2 Gem provides integration with the [Robot Operating System (ROS) 2](https://docs.ros.org/en/rolling/index.html) library and enables design of simulation of robotics systems. |
+| [ROS 2](./robotics/ros2.md) | The ROS 2 Gem provides integration with the [Robot Operating System (ROS) 2](https://docs.ros.org/en/rolling/index.html) library and enables the design of the simulation of robotics systems. |
 
 ## Script
 

content/docs/user-guide/gems/reference/robotics/ros2.md

@@ -0,0 +1,42 @@
+---
+linkTitle: ROS 2
+title: ROS 2 Gem
+description: The ROS 2 Gem helps build robotic simulations with Robot Operating System (ROS) 2 in Open 3D Engine (O3DE).
+toc: true
+---
+
+<!-- # O3DE ROS2 Gem -->
+
+The **ROS 2 Gem** uses the [Robot Operating System (ROS)](https://docs.ros.org/en/rolling/index.htmml) to enable
+robotic simulation in **Open 3D Engine (O3DE)**. The ROS 2 Gem has the following features:
+
+* Direct and natural support of the ROS 2 ecosystem:
+    * Does not use any bridges to communicate between ROS and O3DE. A simulation node will function as any other ROS 2 node.
+        * Enables you to directly include ROS 2 headers and write ROS 2 code in O3DE.
+        * Having no bridge improves communication performance.
+    * Provides an easy way to include ROS 2 dependencies.
+* Sensors:
+    * Are abstracted through the Sensor Component, which takes care of the publishing of sensor data and common settings such as frequency. 
+    * Features several types of configurable, extendable sensors such as Lidar, Camera (including Depth channel), IMU, and GNSS.
+* Utilities for automated handling of:
+    * Simulation time: - publishing `/clock`, with support for non-real time.
+    * Computing and publishing of transformation frames (`/tf`, `/tf_static`).
+    * Namespaces- allowing multi-robot simulation in O3DE by default!
+    * Validation for topic and namespace names.
+    * Dynamic spawning of robots through ROS 2 services.
+* Robot Control Component:
+    * Provides a quick-to-use method of controlling your robot.
+    * Includes support for Twist and AckermannDrive message interfaces.
+* Vehicle dynamics: 
+    * Ackermann Steering subscribes to the message of type [AckermannDrive](http://docs.ros.org/en/api/ackermann_msgs/html/msg/AckermannDrive.html).
+    * Differential drive subscribes to the message of type [Twist](http://docs.ros.org/en/noetic/api/geometry_msgs/html/msg/Twist.html).
+* URDF/XACRO (experimental).
+    * Allows robot imports from the URDF format.
+
+## Related topics
+
+| Topic                                                                                                             | Description                                                                                      |
+|-------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------|
+| [Robotics in O3DE](/docs/user-guide/interactivity/robotics)                                                       | Learn about robotics in O3DE, including Gems, Templates and demos to help you get started.       |
+| [ROS 2 Gem Concepts and Structure](/docs/user-guide/interactivity/robotics/concepts-and-components-overview.md)   | Overview of the concepts and structure of the ROS 2 Gem, including an overview of its components |
+| [ROS 2 Gem API reference](/docs/api/gems/ros2)                                                                    | Generated documentation for ROS 2 Gem's API reference.                                           |