NOVA

Overview

NOVA is a sophisticated rocket flight simulation system designed to analyze and visualize the complex dynamics of rocket launches and atmospheric flight. The simulator provides high-fidelity modeling of various physical phenomena affecting rocket flight, making it valuable for preliminary mission planning and educational purposes.

The system models:

• Gravitational forces with real-time altitude compensation
• Atmospheric effects through multiple layers
• Complex aerodynamic interactions
• Multi-engine propulsion systems
• Real-time fuel consumption and mass changes
• Thrust vectoring via gimbal control
• Flight path visualization and comprehensive data logging

Features In-Depth

1. Physics Simulation Engine

Gravitational Model

• Implements Newton's universal law of gravitation
• Accounts for gravitational field variations with altitude
• Uses Earth's actual mass (5.972e24 kg) and radius (6,371 km)
• Real-time gravitational force calculations based on position

Atmospheric Model

• Multi-layer atmospheric simulation
• Temperature gradient modeling (-6.5°C/km lapse rate)
• Pressure calculations using barometric formula
• Density variations based on ideal gas law
• Scale height consideration (7,400m)

Aerodynamics System

• Comprehensive drag modeling:
  • Subsonic regime (Mach < 0.8): Constant drag coefficient
  • Transonic regime (0.8 ≤ Mach ≤ 1.2): Linear interpolation
  • Supersonic regime (Mach > 1.2): Wave drag consideration
• Lift calculations based on angle of attack
• Dynamic pressure effects
• Reynolds number considerations
• Real-time aerodynamic coefficient updates

2. Advanced Propulsion System

Engine Management

• Multiple engine support with individual characteristics
• Real-time thrust calculations with altitude compensation
• Specific impulse variations with altitude
• Throttle control (0-100%)

Fuel System

• Precise fuel mass tracking
• Real-time consumption calculations
• Mass flow rate modeling
• Center of mass updates based on fuel usage

Thrust Vectoring

• Gimbal control system (±5° range)
• Real-time thrust direction updates
• Independent X and Y axis control
• Automatic thrust direction optimization

3. Data Analysis and Output

Real-time Data Collection

• High-precision time stamping
• Comprehensive state vector logging:
  • Position (x, y, z coordinates)
  • Velocity components
  • Acceleration vectors
  • Current mass
  • Fuel status
  • Engine parameters
  • Atmospheric conditions
  • Flight dynamics

Data Output Format

Flight data is saved to flight_data.csv with columns:

• Time (seconds)
• Altitude (meters)
• Velocity (m/s)
• Acceleration (m/s²)
• Mass (kg)
• Fuel Ratio (0-1)

Requirements

System Requirements

• C++17 compatible compiler (g++ recommended)
• Python 3.x for visualization
• Terminal with ANSI color support
• Minimum 1GB RAM
• x86_64 processor architecture

Software Dependencies

• Standard C++ libraries
• Python libraries (for visualization):
  • matplotlib
  • pandas
  • numpy

Installation & Setup

1. Clone the repository:

git clone https://github.com/thevoxium/NOVA.git
cd nova

2. Ensure you have the required compilers and Python:

g++ --version  # Should be 7.0 or higher
python3 --version  # Should be 3.6 or higher

3. Install Python dependencies:

pip3 install matplotlib pandas numpy

Running NOVA

Basic Execution

Run the simulation with default parameters:

g++ -std=c++17 -I src/ src/main.cpp -o nova && ./nova && python3 screen.py

This command:

1. Compiles the C++ code with C++17 standard
2. Includes headers from src/ directory
3. Creates executable named 'nova'
4. Runs the simulation
5. Launches the Python visualization script

Default Configuration

The simulation starts with these parameters:

• Initial altitude: 100m above sea level
• Rocket specifications:
  • Length: 20 meters
  • Diameter: 2 meters
  • Wet mass: 5000 kg
  • Dry mass: 2000 kg
• Engine specifications:
  • Maximum thrust: 100 kN
  • Specific impulse: 300 seconds
  • Throat area: 0.5 m²
  • Expansion ratio: 20:1
• Initial conditions:
  • Zero initial velocity
  • Vertical orientation
  • Full fuel tanks
  • Sea level atmospheric conditions

Modifying Simulation Parameters

Rocket Configuration

Edit main.cpp to modify rocket parameters:

RocketBody rocket(
    20.0,    // Length (m)
    2.0,     // Diameter (m)
    5000.0,  // Wet mass (kg)
    2000.0   // Dry mass (kg)
);

Engine Settings

Adjust engine parameters in main.cpp:

propulsion.addEngine(
    100000.0,  // Max thrust (N)
    300.0,     // Specific impulse (s)
    0.5,       // Throat area (m²)
    20.0       // Expansion ratio
);

Initial Conditions

Modify the initial state in main.cpp:

State initialState(
    Vec3(Constants::EARTH_RADIUS + 100.0, 0, 0),  // Position
    Vec3(0, 0, 0),                                // Velocity
    Vec3(),                                       // Acceleration
    rocket.getMass(),                             // Mass
    0.0                                           // Initial time
);

Understanding Output

Console Output

During simulation, the console displays:

• Real-time force calculations
• Current altitude
• Velocity magnitude
• Remaining fuel percentage
• Engine status
• Error messages (if any)

Data Visualization

The Python script (screen.py) generates plots showing:

• Altitude vs. Time
• Velocity vs. Time
• Acceleration vs. Time
• Mass vs. Time
• Fuel consumption rate
• Trajectory visualization

Known Limitations

1. Atmospheric Model:

   • No wind effects
   • Simplified temperature gradient
   • No weather conditions

2. Aerodynamics:

   • Basic drag coefficient model
   • Simplified lift calculations
   • No lateral aerodynamic effects

3. Propulsion:

   • Ideal rocket equation assumptions
   • No nozzle flow separation modeling
   • Simplified specific impulse calculations

4. Physics:

   • No Earth rotation effects
   • No Coriolis force
   • No relativistic effects

Troubleshooting

Common Issues

1. Compilation Errors:

   Solution: Ensure C++17 compiler is installed and properly configured
   

2. Python Visualization Errors:

   Solution: Verify Python dependencies are installed correctly
   

3. Data File Access:

   Solution: Check write permissions in the current directory
   

Future Improvements

1. Enhanced Physics:

   • Earth rotation effects
   • Advanced atmospheric modeling
   • Wind effects and turbulence

2. Additional Features:

   • Real-time 3D visualization
   • Multiple stage support
   • Flight control systems
   • Mission planning interface

3. Performance Optimizations:

   • Parallel computation support
   • GPU acceleration
   • Adaptive time stepping

License

MIT

Acknowledgments

• Physical constants from NASA technical documents
• Atmospheric model based on U.S. Standard Atmosphere
• Numerical methods inspired by modern spacecraft dynamics texts