RDC_Simulation/docs/architecture.md

Architecture Overview

Modes

1. Standalone (1 Terminal)

python standalone_simulation.py --pattern circular

┌────────────────────────────────────────┐
│      standalone_simulation.py          │
│  PyBullet + Controllers + Camera       │
└────────────────────────────────────────┘

2. Gazebo + ROS 2 (2 Terminals)

Terminal 1                    Terminal 2
┌───────────────────┐        ┌───────────────────┐
│ Gazebo + Bridge   │◄──────►│ run_gazebo.py     │
└───────────────────┘  ROS   └───────────────────┘

3. ArduPilot GPS-Denied (2 Terminals)

Terminal 1                    Terminal 2
┌───────────────────┐        ┌───────────────────┐
│ Gazebo +          │◄──────►│ ArduPilot SITL    │
│ ArduPilot Plugin  │  JSON  │ + MAVProxy        │
└───────────────────┘        └───────────────────┘

Data Flow

Standalone

Controller → PyBullet → Telemetry → Controller

Gazebo

Controller → /cmd_vel → Gazebo → /odometry → Controller

ArduPilot

Gazebo ◄─── JSON/UDP ───► SITL ◄─── MAVLink ───► MAVProxy

Key Files

File	Purpose
drone_controller.py	Your landing algorithm
gazebo_bridge.py	Gazebo ↔ ROS bridge
camera_viewer.py	Camera display
config.py	Configuration

GPS-Denied Sensors

Sensor	Data
IMU	Orientation, angular velocity
Altimeter	Altitude, vertical velocity
Camera	Downward image
Landing Pad	Relative position

Topics

Topic	Direction
/cmd_vel	→ Drone commands
/drone/telemetry	← Sensor data
/drone/camera	← Camera images