torque#

This module provides the functionality for creating torque settings.

Functions#

aerodynamic()

Creates the settings for the aerodynamic torque.

spherical_harmonic_gravitational(...)

Creates the settings for the spherical harmonic torque.

second_degree_gravitational()

Creates the settings for the second-degree gravitational torque.

custom(torque_function[, scaling_function])

Creates the settings for a custom torque.

aerodynamic() tudatpy.kernel.numerical_simulation.propagation_setup.torque.TorqueSettings#

Creates the settings for the aerodynamic torque.

Creates the settings for the aerodynamic torque exerted by a body with an atmosphere model and shape model on another body. The body exerting the torque needs to have both an atmosphere model and a shape model defined. Furthermore, the body undergoing the torque needs to have the aerodynamic coefficient interface and its moment coefficients defined. In the case that the aerodynamic coefficients are defined as a function of the vehicle orientation (e.g. angle of attack and sideslip angle), these angles can be manually or automatically defined.

Returns

Torque settings object.

Return type

TorqueSettings

Examples

In this example, we define the aerodynamic torque exerted by the Earth on the vehicle.

# Create torque settings dict
torque_settings_vehicle = {}
# Add aerodynamic torque exerted by the Earth on the vehicle
torque_settings_vehicle["Earth"] = [propagation_setup.torque.aerodynamic()]
spherical_harmonic_gravitational(maximum_degree: int, maximum_order: int) tudatpy.kernel.numerical_simulation.propagation_setup.torque.TorqueSettings#

Creates the settings for the spherical harmonic torque.

Torque exerted by a point mass on a body with an arbitrary degree/order spherical harmonics mass distribution. The body exerting the torque only needs to have a gravitational model defined (point-mass or spherical harmonic), while the body undergoing the torque needs to have a spherical harmonic gravity field defined.

Parameters
  • maximum_degree (int) – Maximum degree of the spherical harmonic expansion.

  • maximum_order (int) – Maximum order of the spherical harmonic expansion.

Returns

Torque settings object.

Return type

TorqueSettings

Examples

In this example, we define the spherical harmonic gravitational torque (up to degree 4 and order 4) exerted by the Earth on the vehicle.

# Create torque settings dict
torque_settings_vehicle = {}
# Add aerodynamic torque exerted by the Earth on the vehicle
torque_settings_vehicle["Earth"] = [propagation_setup.torque.spherical_harmonic_gravitational(4, 4)]
second_degree_gravitational() tudatpy.kernel.numerical_simulation.propagation_setup.torque.TorqueSettings#

Creates the settings for the second-degree gravitational torque.

Torque exerted by a point mass on a body with a degree two spherical harmonics mass distribution. A degree two spherical harmonics mass distribution can be represented by an inertia tensor; thus, for this torque model, the body undergoing the torque needs to have an inertia tensor defined. The body exerting the torque only needs to have a gravitational model defined (either point-mass or spherical harmonics).

Returns

Torque settings object.

Return type

TorqueSettings

Examples

In this example, we define the second degree gravitational torque exerted by the Earth on the vehicle.

# Create torque settings dict
torque_settings_vehicle = {}
# Add aerodynamic torque exerted by the Earth on the vehicle
torque_settings_vehicle["Earth"] = [propagation_setup.torque.second_degree_gravitational()]
custom(torque_function: Callable[[float], numpy.ndarray[numpy.float64[3, 1]]], scaling_function: Callable[[float], float] = None) tudatpy.kernel.numerical_simulation.propagation_setup.torque.TorqueSettings#

Creates the settings for a custom torque.

Creates settings for a custom torque. This torque must be parameterized as a function of time and expressed with an inertial orientation.

Parameters
  • torque_function (callable[[float], list]) – Custom torque function with time as an independent variable.

  • scaling_function (callable[[float], float], default=None) – Scaling function with time as an independent variable to be multiplied by the custom torque function.

Returns

Torque settings object.

Return type

TorqueSettings

Examples

In this example, we define a custom torque exerted by the Earth on the vehicle.

# Create torque function
def torque_function(time: float):
    # Compute torque
    torque = ...
    return torque

# Create torque settings dict
torque_settings_vehicle = {}
# Add aerodynamic torque exerted by the Earth on the vehicle
torque_settings_vehicle["Earth"] = [propagation_setup.torque.custom(torque_function)]

Enumerations#

AvailableTorque

Enumeration of available torque types.

class AvailableTorque#

Enumeration of available torque types.

Enumeration of torque types supported by tudat.

Members:

torque_free_type :

underfined_type : No documentation found.

second_order_gravitational_type : No documentation found.

aerodynamic_type : No documentation found.

spherical_harmonic_gravitational_type : No documentation found.

inertial_type : No documentation found.

dissipative_type : No documentation found.

property name#

Classes#

TorqueSettings

Functional base class to define settings for torques.

SphericalHarmonicTorqueSettings

TorqueSettings-derived class to define settings for torques caused by spherical harmonic gravity.

class TorqueSettings#

Functional base class to define settings for torques.

This is a functional base class to define settings for torques that require no information in addition to their type. Classes defining settings for torque models requiring additional information must be derived from this class. Bodies exerting and undergoing torque are set outside of this class. This class can be used for the easy setup of torque models (see createTorqueModels.h), but users may also chose to do so manually. (Derived) Class members are all public, for ease of access and modification.

class SphericalHarmonicTorqueSettings#

TorqueSettings-derived class to define settings for torques caused by spherical harmonic gravity.

TorqueSettings-derived class to define settings for torques caused by spherical harmonic gravity.