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🤖 AI Learning Companion

Agent Skills:

Module 2: The Digital Twin (Gazebo & Unity)

Focus: Physics simulation and environment building.

Curriculum​

  1. Simulating Physics: Understanding gravity, collisions, and friction in Gazebo.
  2. Unity Integration: High-fidelity rendering and human-robot interaction in Unity.
  3. Sensor Simulation: Simulating LiDAR, Depth Cameras, and IMUs.

The Digital Twin Concept​

Before deploying to physical hardware, we simulate our robots in a "Digital Twin" environment. This allows us to train AI models safely and rapidly.

Gazebo​

Standard for ROS 2 physics simulation.

# Example launch command (mock)
ros2 launch gazebo_ros gazebo.launch.py

Unity​

Used for high-quality visual simulation, crucial for Vision-Language models. Digital Twin—a high-fidelity virtual replica of the robot and its environment. This module covers Gazebo for physics simulation and Unity for advanced rendering and interaction.

Gazebo​

Gazebo is the standard simulator for ROS. It handles:

  • Rigid Body Dynamics: Simulating gravity, friction, and collisions using physics engines like ODE or Bullet.
  • Plugins: C++ code that controls the simulation (e.g., a plugin to simulate a differential drive motor).

Creating a World​

A Gazebo world file (.world) defines the environment.

<sdf version="1.6">
  <world name="default">
    <include>
      <uri>model://sun</uri>
    </include>
    <include>
      <uri>model://ground_plane</uri>
    </include>
    <!-- Add your robot here -->
  </world>
</sdf>

Why Digital Twins?​

  • Safety: Test dangerous maneuvers without breaking hardware.
  • Scalability: Train multiple robots in parallel.
  • Speed: Run simulations faster than real-time.