Package org.orekit.forces.gravity

Class Relativity

java.lang.Object

org.orekit.forces.gravity.Relativity

All Implemented Interfaces:

ForceModel, EventDetectorsProvider, BaseParameterDriversProvider<ParameterDriver,ParameterObserver>, ParameterDriversProvider

public class Relativity
extends Object
implements ForceModel

Post-Newtonian correction force due to general relativity. The main effect is the precession of periapsis by a few arcseconds per year.

Implemented from Montenbruck and Gill equation 3.146.

Author:

Evan Ward

See Also:

• "Montenbruck, Oliver, and Gill, Eberhard. Satellite orbits : models, methods, and applications. Berlin New York: Springer, 2000."

Field Summary

Fields inherited from interface org.orekit.propagation.events.EventDetectorsProvider

DATATION_ACCURACY

Constructor Summary

Constructors

Constructor	Description
Relativity(double gm)	Create a force model to add post-Newtonian acceleration corrections to an Earth orbit.

Method Summary

Modifier and Type	Method	Description
<T extends CalculusFieldElement<T>> FieldVector3D<T>	acceleration(FieldSpacecraftState<T> s, T[] parameters)	Compute acceleration.
Vector3D	acceleration(SpacecraftState s, double[] parameters)	Compute acceleration.
List<ParameterDriver>	getParametersDrivers()	Get the drivers for parameters.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.orekit.utils.drivers.BaseParameterDriversProvider

getParameterDriver, getParameterDriverWithSubstring, isSupported

Methods inherited from interface org.orekit.propagation.events.EventDetectorsProvider

getDateDetector, getEventDetectors, getFieldDateDetector, getFieldEventDetectors

Methods inherited from interface org.orekit.forces.ForceModel

addContribution, addContribution, dependsOnAttitudeRate, dependsOnPositionOnly, getEventDetectors, getFieldEventDetectors, getMassDerivative, getMassDerivative, init, init

Methods inherited from interface org.orekit.utils.drivers.ParameterDriversProvider

getParameters, getParameters

Constructor Details

Relativity

public Relativity(double gm)

Create a force model to add post-Newtonian acceleration corrections to an Earth orbit.

Parameters:

gm - Earth's gravitational parameter.

Method Details

acceleration

public Vector3D acceleration(SpacecraftState s,
 double[] parameters)

Compute acceleration.

Specified by:

acceleration in interface ForceModel

Parameters:

s - current state information: date, kinematics, attitude

parameters - values of the force model parameters at state date, only 1 value for each parameterDriver

Returns:

acceleration in same frame as state

acceleration

public <T extends CalculusFieldElement<T>>
FieldVector3D<T> acceleration(FieldSpacecraftState<T> s,
 T[] parameters)

Compute acceleration.

Specified by:

acceleration in interface ForceModel

Type Parameters:

T - type of the elements

Parameters:

s - current state information: date, kinematics, attitude

parameters - values of the force model parameters at state date, only 1 value for each parameterDriver

Returns:

acceleration in same frame as state

getParametersDrivers

public List<ParameterDriver> getParametersDrivers()

Get the drivers for parameters. By default, no parameters. Override, for instance, to enable partial derivatives.

Specified by:

getParametersDrivers in interface BaseParameterDriversProvider<ParameterDriver,ParameterObserver>

Specified by:

getParametersDrivers in interface ForceModel

Returns:

drivers for parameters