RCAIDE.Library.Methods.Mass_Properties.Center_of_Gravity.update_center_of_gravity

update_center_of_gravity#

update_center_of_gravity(state, vehicle)[source]#

Updates the vehicle center of gravity accounting for fuel consumption during flight.

Parameters:

  • vehicle (RCAIDE.Library.Components.Vehicle) –

    Vehicle object containing all components and fuel systems
    • networkslist

      List of propulsion networks

    • fuel_lineslist

      List of fuel lines within each network

    • fuel_tankslist
      List of fuel tanks within each fuel line
      • fuelRCAIDE.Library.Components.Energy.Storages.Fuel
        Fuel component with mass properties
        • mass_propertiesData
          • massfloat

            Current fuel mass [kg]

          • center_of_gravitylist

            Fuel tank center of gravity [m]

        • originlist

          Fuel tank origin location [m]

  • conditions (RCAIDE.Framework.Core.Data) –

    Flight conditions and state data

    • aerodynamics : Data

    • weights : Data

Returns:

CG – Updated center of gravity coordinates [m] Shape: (3, N) where N is the number of flight conditions

Return type:

numpy.ndarray

Notes

This function calculates the updated center of gravity of the vehicle by accounting for fuel consumption during flight. It computes the mass and moment contributions of remaining fuel and combines them with the dry vehicle mass and moment to determine the new center of gravity location.

Major Assumptions

  • Fuel tank locations and orientations remain constant

  • No fuel sloshing or redistribution effects

  • Vehicle structure mass remains constant

  • Fuel density is constant

Theory

The center of gravity is calculated using the principle of moments: \(\vec{r}_{CG} = \frac{\sum m_i \vec{r}_i}{\sum m_i}\)

where \(m_i\) is the mass of component \(i\) and \(\vec{r}_i\) is its position.

Definitions

‘Center of Gravity’

Point where the total mass of the vehicle can be considered to act.