Package org.orekit.forces.maneuvers

Class FieldImpulseManeuver<D extends FieldEventDetector<T>,T extends CalculusFieldElement<T>>

java.lang.Object

org.orekit.propagation.events.FieldAbstractDetector<FieldImpulseManeuver<D,T>,T>

org.orekit.forces.maneuvers.FieldImpulseManeuver<D,T>

Type Parameters:

D - type of the detector

T - type of the field elements

All Implemented Interfaces:

FieldEventDetector<T>

public class FieldImpulseManeuver<D extends FieldEventDetector<T>,T extends CalculusFieldElement<T>>
extends FieldAbstractDetector<FieldImpulseManeuver<D,T>,T>

Impulse maneuver model for propagators working with Fields.

This class implements an impulse maneuver as a discrete event that can be provided to any Propagator and mirrors the standard version ImpulseManeuver.

The maneuver is triggered when an underlying event generates a STOP event, in which case this class will generate a RESET_STATE event (the stop event from the underlying object is therefore filtered out). In the simple cases, the underlying event detector may be a basic date event, but it can also be a more elaborate apside event for apogee maneuvers for example.

The maneuver is defined by a single velocity increment. If no AttitudeProvider is given, the current attitude of the spacecraft, defined by the current spacecraft state, will be used as the AttitudeProvider so the velocity increment should be given in the same pseudoinertial frame as the FieldSpacecraftState used to construct the propagator that will handle the maneuver. If an AttitudeProvider is given, the velocity increment given should be defined appropriately in consideration of that provider. So, a typical case for tangential maneuvers is to provide a LOF aligned attitude provider along with a velocity increment defined in accordance with that LOF aligned attitude provider; e.g. if the LOF aligned attitude provider was constructed using LOFType.VNC the velocity increment should be provided in VNC coordinates.

The norm through which the delta-V maps to the mass consumption is chosen via the enum Control3DVectorCostType. Default is Euclidean.

Beware that the triggering event detector must behave properly both before and after maneuver. If for example a node detector is used to trigger an inclination maneuver and the maneuver change the orbit to an equatorial one, the node detector will fail just after the maneuver, being unable to find a node on an equatorial orbit! This is a real case that has been encountered during validation ...

Since:

12.0

Author:

Romain Serra

See Also:

FieldPropagator.addEventDetector(FieldEventDetector), ImpulseManeuver

Field Summary

Fields inherited from class org.orekit.propagation.events.FieldAbstractDetector

DEFAULT_MAX_ITER, DEFAULT_MAXCHECK, DEFAULT_THRESHOLD

Constructor Summary

Constructors

Constructor	Description
FieldImpulseManeuver(D trigger, FieldVector3D<T> deltaVSat, T isp)	Build a new instance.
FieldImpulseManeuver(D trigger, AttitudeProvider attitudeOverride, FieldVector3D<T> deltaVSat, T isp)	Build a new instance.
FieldImpulseManeuver(D trigger, AttitudeProvider attitudeOverride, FieldVector3D<T> deltaVSat, T isp, Control3DVectorCostType control3DVectorCostType)	Build a new instance.

Method Summary

Modifier and Type	Method	Description
protected FieldImpulseManeuver<D,T>	create(FieldAdaptableInterval<T> newMaxCheck, T newThreshold, int newMaxIter, FieldEventHandler<T> fieldEventHandler)	Build a new instance.
T	g(FieldSpacecraftState<T> fieldSpacecraftState)	Compute the value of the switching function.
AttitudeProvider	getAttitudeOverride()	Get the Attitude Provider to use during maneuver.
Control3DVectorCostType	getControl3DVectorCostType()	Get the control vector's cost type.
FieldVector3D<T>	getDeltaVSat()	Get the velocity increment in satellite frame.
T	getIsp()	Get the specific impulse.
FieldEventDetector<T>	getTrigger()	Get the triggering event.
void	init(FieldSpacecraftState<T> s0, FieldAbsoluteDate<T> t)	Initialize event handler at the start of a propagation.

Methods inherited from class org.orekit.propagation.events.FieldAbstractDetector

getHandler, getMaxCheckInterval, getMaxIterationCount, getThreshold, isForward, withHandler, withMaxCheck, withMaxCheck, withMaxIter, withThreshold

Methods inherited from class java.lang.Object

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

Constructor Detail

FieldImpulseManeuver

public FieldImpulseManeuver(D trigger,
                            FieldVector3D<T> deltaVSat,
                            T isp)

Build a new instance.

Parameters:

trigger - triggering event

deltaVSat - velocity increment in satellite frame

isp - engine specific impulse (s)

FieldImpulseManeuver

public FieldImpulseManeuver(D trigger,
                            AttitudeProvider attitudeOverride,
                            FieldVector3D<T> deltaVSat,
                            T isp)

Build a new instance.

Parameters:

trigger - triggering event

attitudeOverride - the attitude provider to use for the maneuver

deltaVSat - velocity increment in satellite frame

isp - engine specific impulse (s)

FieldImpulseManeuver

public FieldImpulseManeuver(D trigger,
                            AttitudeProvider attitudeOverride,
                            FieldVector3D<T> deltaVSat,
                            T isp,
                            Control3DVectorCostType control3DVectorCostType)

Build a new instance.

Parameters:

trigger - triggering event

attitudeOverride - the attitude provider to use for the maneuver

deltaVSat - velocity increment in satellite frame

isp - engine specific impulse (s)

control3DVectorCostType - increment's norm for mass consumption

Method Detail

create

protected FieldImpulseManeuver<D,T> create(FieldAdaptableInterval<T> newMaxCheck,
                                                 T newThreshold,
                                                 int newMaxIter,
                                                 FieldEventHandler<T> fieldEventHandler)

Build a new instance.

Specified by:

create in class FieldAbstractDetector<FieldImpulseManeuver<D extends FieldEventDetector<T>,T extends CalculusFieldElement<T>>,T extends CalculusFieldElement<T>>

Parameters:

newMaxCheck - maximum checking interval

newThreshold - convergence threshold (s)

newMaxIter - maximum number of iterations in the event time search

fieldEventHandler - event handler to call at event occurrences

Returns:

a new instance of the appropriate sub-type

init

public void init(FieldSpacecraftState<T> s0,
                 FieldAbsoluteDate<T> t)

Initialize event handler at the start of a propagation.

This method is called once at the start of the propagation. It may be used by the event handler to initialize some internal data if needed.

The default implementation does nothing

Specified by:

init in interface FieldEventDetector<D extends FieldEventDetector<T>>

Overrides:

init in class FieldAbstractDetector<FieldImpulseManeuver<D extends FieldEventDetector<T>,T extends CalculusFieldElement<T>>,T extends CalculusFieldElement<T>>

Parameters:

s0 - initial state

t - target time for the integration

g

public T g(FieldSpacecraftState<T> fieldSpacecraftState)

Compute the value of the switching function. This function must be continuous (at least in its roots neighborhood), as the integrator will need to find its roots to locate the events.

Specified by:

g in interface FieldEventDetector<D extends FieldEventDetector<T>>

Specified by:

g in class FieldAbstractDetector<FieldImpulseManeuver<D extends FieldEventDetector<T>,T extends CalculusFieldElement<T>>,T extends CalculusFieldElement<T>>

Parameters:

fieldSpacecraftState - the current state information: date, kinematics, attitude

Returns:

value of the switching function

getAttitudeOverride

public AttitudeProvider getAttitudeOverride()

Get the Attitude Provider to use during maneuver.

Returns:

the attitude provider

getTrigger

public FieldEventDetector<T> getTrigger()

Get the triggering event.

Returns:

triggering event

getDeltaVSat

public FieldVector3D<T> getDeltaVSat()

Get the velocity increment in satellite frame.

Returns:

velocity increment in satellite frame

getIsp

public T getIsp()

Get the specific impulse.

Returns:

specific impulse

getControl3DVectorCostType

public Control3DVectorCostType getControl3DVectorCostType()

Get the control vector's cost type.

Returns:

control cost type

Since:

12.0