agi.foundation.celestial

(agi.foundation.orbitpropagation-2025r1.jar)

Class MagneticCoilTorque

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.celestial.TorqueModel

agi.foundation.celestial.MagneticCoilTorque

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

public class MagneticCoilTorque
extends TorqueModel

Represents the torque effects of a magnetic field vector on a magnetic torquer coil implemented on a spacecraft parameterized by a PropagationEulerianAxes.

Constructor Summary

Constructors

Modifier	Constructor and Description
	MagneticCoilTorque() Initializes the magnetic coil torque model.
protected	MagneticCoilTorque(MagneticCoilTorque existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
	MagneticCoilTorque(Vector magneticFieldVector, double numberOfLoops, Scalar current, Cartesian directedArea, Axes bodyAxes) Initializes the magnetic coil torque model.
	MagneticCoilTorque(Vector magneticFieldVector, double numberOfLoops, Scalar current, Vector directedArea, Axes bodyAxes) Initializes the magnetic coil torque model.

Method Summary

Modifier and Type	Method and Description
void	buildTorqueEvaluator(ResultantTorqueBuilder builder, EvaluatorGroup group) Build lists of torques based on this model in order to create an overall resultant torque.
protected boolean	checkForSameDefinition(MagneticCoilTorque other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(TorqueModel other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
Object	clone(CopyContext context) Clones this object using the specified context.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
static MagneticCoilTorque	createMagneticCoilTorqueUsingIgrfCofModel(String filename, Point bodyCenterOfMass, double numberOfLoops, Scalar current, Vector directedArea, Axes bodyAxes) Creates a new magnetic coil torque that uses an InternationalGeomagneticReferenceFieldVector to describe the magnetic field and a Point to describe the position of the spacecraft.
static MagneticCoilTorque	createMagneticCoilTorqueUsingIgrfTxtModel(String filename, Point bodyCenterOfMass, double numberOfLoops, Scalar current, Vector directedArea, Axes bodyAxes) Creates a new magnetic coil torque that uses an InternationalGeomagneticReferenceFieldVector to describe the magnetic field and a Point to describe the position of the spacecraft.
static MagneticCoilTorque	createMagneticCoilTorqueUsingWmmModel(String filename, Point bodyCenterOfMass, double numberOfLoops, Scalar current, Vector directedArea, Axes bodyAxes) Creates a new magnetic coil torque that uses a WorldMagneticModelVector to describe the magnetic field and a Point to describe the position of the spacecraft.
void	enumerateDependencies(DependencyEnumerator enumerator) Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon.
Axes	getBodyAxes() Gets the body axes of the spacecraft.
Scalar	getCurrent() Gets the electric current passing through the coil.
Vector	getDirectedArea() Gets the area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.
Vector	getMagneticFieldVector() Gets a vector describing the magnetic field that the coil is subjected to.
double	getNumberOfLoops() Gets the number of current loops in the magnetic torquer coil.
TorqueEvaluator	getTorqueEvaluator(EvaluatorGroup group) Gets an instance of an evaluator that can compute the torque.
void	setBodyAxes(Axes value) Sets the body axes of the spacecraft.
void	setCurrent(Scalar value) Sets the electric current passing through the coil.
void	setDirectedArea(Vector value) Sets the area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.
void	setMagneticFieldVector(Vector value) Sets a vector describing the magnetic field that the coil is subjected to.
void	setNumberOfLoops(double value) Sets the number of current loops in the magnetic torquer coil.

Methods inherited from class agi.foundation.celestial.TorqueModel

checkForSameDefinition, freezeAggregatedObjects, getTorqueEvaluator, getTorqueVector

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, freeze, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

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

Constructor Detail

MagneticCoilTorque

public MagneticCoilTorque()

Initializes the magnetic coil torque model. The MagneticFieldVector (get / set), NumberOfLoops (get / set), Current (get / set), DirectedArea (get / set), and BodyAxes (get / set) will have to be set before an evaluator is created.

MagneticCoilTorque

public MagneticCoilTorque(Vector magneticFieldVector,
                          double numberOfLoops,
                          Scalar current,
                          @Nonnull
                          Cartesian directedArea,
                          Axes bodyAxes)

Initializes the magnetic coil torque model.

Parameters:

magneticFieldVector - A vector describing the magnetic field that the coil is subjected to. This is usually a MagneticFieldVector (get / set).

numberOfLoops - The number of current loops in the magnetic torquer coil.

current - The electric current passing through the coil.

directedArea - The area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule. In this constructor, the Cartesian value is converted into a VectorFixed in the bodyAxes.

bodyAxes - The body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

MagneticCoilTorque

public MagneticCoilTorque(Vector magneticFieldVector,
                          double numberOfLoops,
                          Scalar current,
                          Vector directedArea,
                          Axes bodyAxes)

Initializes the magnetic coil torque model.

Parameters:

magneticFieldVector - A vector describing the magnetic field that the coil is subjected to. This is usually a MagneticFieldVector (get / set).

numberOfLoops - The number of current loops in the magnetic torquer coil.

current - The electric current passing through the coil.

directedArea - The area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.

bodyAxes - The body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

MagneticCoilTorque

protected MagneticCoilTorque(MagneticCoilTorque existingInstance,
                             CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

clone

public Object clone(CopyContext context)

Clones this object using the specified context.

This method should be implemented to call a copy constructor on the class of the object being cloned. The copy constructor should take the CopyContext as a parameter in addition to the existing instance to copy. The copy constructor should first call CopyContext.addObjectMapping(T, T) to identify the newly constructed instance as a copy of the existing instance. It should then copy all fields, using CopyContext.updateReference(T) to copy any reference fields.

A typical implementation of ICloneWithContext:

public static class MyClass implements ICloneWithContext {
    public MyClass(MyClass existingInstance, CopyContext context) {
        context.addObjectMapping(existingInstance, this);
        someReference = context.updateReference(existingInstance.someReference);
    }

    @Override
    public final Object clone(CopyContext context) {
        return new MyClass(this, context);
    }

    private Object someReference;
}

In general, all fields that are reference types should be copied with a call to CopyContext.updateReference(T). There are a couple of exceptions:

1. Fields that are aggregate parts of the object should always be copied. A referenced object is an aggregate if properties or methods on the object being copied can modify the externally-visible value of the referenced object.
2. If the semantics of the referenced object require that it have a single parent, owner, context, etc., and the object being copied is that parent, owner, or context, then the referenced object should always be copied.

If one of these exceptions applies, the CopyContext should be given an opportunity to update the reference before the reference is copied explicitly. Use CopyContext.updateReference(T) to update the reference. If CopyContext.updateReference(T) returns the original object, indicating that the context does not have a replacement registered, then copy the object manually by invoking a Clone method, a copy constructor, or by manually constructing a new instance and copying the values.

alwaysCopy = context.updateReference(existingInstance.alwaysCopy);
if (existingInstance.alwaysCopy != null && alwaysCopy == existingInstance.alwaysCopy) {
    alwaysCopy = (AlwaysCopy) existingInstance.alwaysCopy.clone(context);
}

If you are implementing an evaluator (a class that implements IEvaluator), the IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) method shares some responsibilities with the copy context constructor. Code duplication can be avoided by doing the following:

1. For references to other evaluators ONLY, simply assign the reference in the constructor instead of calling CopyContext.updateReference(T). You should still call CopyContext.updateReference(T) on any references to non-evaluators.
2. Call IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as the last line in the constructor and pass it the same CopyContext passed to the constructor.
3. Implement IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as normal. See the reference documentation for IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) for more information on implementing that method.

public MyClass(MyClass existingInstance, CopyContext context) {
    super(existingInstance, context);
    someReference = context.updateReference(existingInstance.someReference);
    evaluatorReference = existingInstance.evaluatorReference;
    updateEvaluatorReferences(context);
}

@Override
public void updateEvaluatorReferences(CopyContext context) {
    evaluatorReference = context.updateReference(evaluatorReference);
}

@Override
public Object clone(CopyContext context) {
    return new MyClass(this, context);
}

private Object someReference;
private IEvaluator evaluatorReference;

Specified by:

clone in interface ICloneWithContext

Specified by:

clone in class DefinitionalObject

Parameters:

context - The context to use to perform the copy.

Returns:

A new instance which is a copy of this object.

checkForSameDefinition

protected final boolean checkForSameDefinition(TorqueModel other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class TorqueModel

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected boolean checkForSameDefinition(MagneticCoilTorque other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the MagneticCoilTorque.checkForSameDefinition(agi.foundation.celestial.TorqueModel) method.

Overrides:

computeCurrentDefinitionHashCode in class TorqueModel

Returns:

The computed hash code.

enumerateDependencies

public void enumerateDependencies(DependencyEnumerator enumerator)

Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class.

Specified by:

enumerateDependencies in interface IEnumerateDependencies

Overrides:

enumerateDependencies in class TorqueModel

Parameters:

enumerator - The enumerator that is informed of the dependencies of this object.

getMagneticFieldVector

public final Vector getMagneticFieldVector()

Gets a vector describing the magnetic field that the coil is subjected to. This is usually a MagneticFieldVector (get / set).

setMagneticFieldVector

public final void setMagneticFieldVector(Vector value)

Sets a vector describing the magnetic field that the coil is subjected to. This is usually a MagneticFieldVector (get / set).

getNumberOfLoops

public final double getNumberOfLoops()

Gets the number of current loops in the magnetic torquer coil.

setNumberOfLoops

public final void setNumberOfLoops(double value)

Sets the number of current loops in the magnetic torquer coil.

getCurrent

public final Scalar getCurrent()

Gets the electric current passing through the coil.

setCurrent

public final void setCurrent(Scalar value)

Sets the electric current passing through the coil.

getDirectedArea

public final Vector getDirectedArea()

Gets the area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.

setDirectedArea

public final void setDirectedArea(Vector value)

Sets the area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.

getBodyAxes

public final Axes getBodyAxes()

Gets the body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

setBodyAxes

public final void setBodyAxes(Axes value)

Sets the body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

createMagneticCoilTorqueUsingWmmModel

@Nonnull
public static MagneticCoilTorque createMagneticCoilTorqueUsingWmmModel(@Nonnull
                                                                                 String filename,
                                                                                 Point bodyCenterOfMass,
                                                                                 double numberOfLoops,
                                                                                 Scalar current,
                                                                                 Vector directedArea,
                                                                                 Axes bodyAxes)

Creates a new magnetic coil torque that uses a WorldMagneticModelVector to describe the magnetic field and a Point to describe the position of the spacecraft.

Parameters:

filename - String file path for WMM file.

bodyCenterOfMass - The center of mass of the Earth-orbiting spacecraft.

numberOfLoops - The number of current loops in the magnetic torquer coil.

current - The electric current passing through the coil.

directedArea - The area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.

bodyAxes - The body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

Returns:

A new magnetic coil torque that uses the WMM model to describe the magnetic field.

Throws:

ArgumentNullException - Thrown if the filename is null.

createMagneticCoilTorqueUsingIgrfTxtModel

@Nonnull
public static MagneticCoilTorque createMagneticCoilTorqueUsingIgrfTxtModel(@Nonnull
                                                                                     String filename,
                                                                                     Point bodyCenterOfMass,
                                                                                     double numberOfLoops,
                                                                                     Scalar current,
                                                                                     Vector directedArea,
                                                                                     Axes bodyAxes)

Creates a new magnetic coil torque that uses an InternationalGeomagneticReferenceFieldVector to describe the magnetic field and a Point to describe the position of the spacecraft.

Parameters:

filename - String file path for IGRF .txt file.

bodyCenterOfMass - The center of mass of the Earth-orbiting spacecraft.

numberOfLoops - The number of current loops in the magnetic torquer coil.

current - The electric current passing through the coil.

directedArea - The area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.

bodyAxes - The body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

Returns:

A new magnetic coil torque that uses the IGRF model to describe the magnetic field.

Throws:

ArgumentNullException - Thrown if the filename is null.

createMagneticCoilTorqueUsingIgrfCofModel

@Nonnull
public static MagneticCoilTorque createMagneticCoilTorqueUsingIgrfCofModel(@Nonnull
                                                                                     String filename,
                                                                                     Point bodyCenterOfMass,
                                                                                     double numberOfLoops,
                                                                                     Scalar current,
                                                                                     Vector directedArea,
                                                                                     Axes bodyAxes)

Creates a new magnetic coil torque that uses an InternationalGeomagneticReferenceFieldVector to describe the magnetic field and a Point to describe the position of the spacecraft.

Parameters:

filename - String file path for IGRF .COF file.

bodyCenterOfMass - The center of mass of the spacecraft.

numberOfLoops - The number of current loops in the magnetic torquer coil.

current - The electric current passing through the coil.

directedArea - The area of the coil multiplied by the unit vector that is normal to the plane of the coil such that a positive current traveling through the coil obeys the right hand rule.

bodyAxes - The body axes of the spacecraft. These should be the IntegrationAxes (get) of the PropagationEulerianAxes associated with the spacecraft.

Returns:

A new magnetic coil torque that uses the IGRF model to describe the magnetic field.

Throws:

ArgumentNullException - Thrown if the filename is null.

getTorqueEvaluator

public TorqueEvaluator getTorqueEvaluator(EvaluatorGroup group)

Gets an instance of an evaluator that can compute the torque.

Overrides:

getTorqueEvaluator in class TorqueModel

Parameters:

group - The group in which to create the evaluator and its dependents.

Returns:

The evaluator that computes the torque.

Throws:

ArgumentNullException - Thrown when group is null.

buildTorqueEvaluator

public void buildTorqueEvaluator(ResultantTorqueBuilder builder,
                                 EvaluatorGroup group)

Build lists of torques based on this model in order to create an overall resultant torque.

Specified by:

buildTorqueEvaluator in class TorqueModel

Parameters:

builder - The builder object containing the lists and additional information on the Axes in which the overall resultant is defined.

group - The evaluator group in which to create evaluators.