org.orekit.forces.maneuvers

Class ConstantThrustManeuver

java.lang.Object

org.orekit.forces.AbstractForceModel

org.orekit.forces.maneuvers.Maneuver

org.orekit.forces.maneuvers.ConstantThrustManeuver

All Implemented Interfaces:

ForceModel, ParametersDriversProvider

public class ConstantThrustManeuver
extends Maneuver

This class implements a simple maneuver with constant thrust.

The maneuver is defined by a direction in satellite frame. The current attitude of the spacecraft, defined by the current spacecraft state, will be used to compute the thrust direction in inertial frame. A typical case for tangential maneuvers is to use a LOF aligned attitude provider for state propagation and a velocity increment along the +X satellite axis.

Author:

Fabien Maussion, Véronique Pommier-Maurussane, Luc Maisonobe, Maxime Journot

Constructor Summary

Constructors

Constructor and Description
ConstantThrustManeuver(AbsoluteDate date, double duration, AttitudeProvider attitudeOverride, AbstractConstantThrustPropulsionModel constantThrustPropulsionModel) Simple constructor for a constant direction and constant thrust.
ConstantThrustManeuver(AbsoluteDate date, double duration, double thrust, double isp, AttitudeProvider attitudeOverride, Vector3D direction) Simple constructor for a constant direction and constant thrust.
ConstantThrustManeuver(AbsoluteDate date, double duration, double thrust, double isp, AttitudeProvider attitudeOverride, Vector3D direction, String name) Simple constructor for a constant direction and constant thrust.
ConstantThrustManeuver(AbsoluteDate date, double duration, double thrust, double isp, Vector3D direction) Simple constructor for a constant direction and constant thrust.
ConstantThrustManeuver(AbsoluteDate date, double duration, double thrust, double isp, Vector3D direction, String name) Simple constructor for a constant direction and constant thrust.
ConstantThrustManeuver(AttitudeProvider attitudeOverride, DateBasedManeuverTriggers dateBasedManeuverTriggers, AbstractConstantThrustPropulsionModel constantThrustPropulsionModel) Simple constructor for a constant direction and constant thrust.

Method Summary

Modifier and Type	Method and Description
Vector3D	getDirection() Get the direction.
double	getDuration() Get the duration of the maneuver (s).
AbsoluteDate	getEndDate() Get the end date.
double	getFlowRate() Get the flow rate.
double	getISP() Get the specific impulse.
AbsoluteDate	getStartDate() Get the start date.
double	getThrust() Get the thrust.
Vector3D	getThrustVector() Get the thrust vector (N) in S/C frame.
boolean	isFiring(AbsoluteDate date) Check if maneuvering is on.
<T extends CalculusFieldElement<T>> boolean	isFiring(FieldSpacecraftState<T> s) Check if maneuvering is on.
boolean	isFiring(SpacecraftState s) Check if maneuvering is on.

Methods inherited from class org.orekit.forces.maneuvers.Maneuver

acceleration, acceleration, addContribution, addContribution, dependsOnPositionOnly, getAttitudeOverride, getEventsDetectors, getFieldEventsDetectors, getManeuverTriggers, getName, getParametersDrivers, getPropulsionModel, init, init

Methods inherited from class org.orekit.forces.AbstractForceModel

complainIfNotSupported, getParameterDriver, isSupported

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.forces.ForceModel

getParameters, getParameters

Constructor Detail

ConstantThrustManeuver

public ConstantThrustManeuver(AbsoluteDate date,
                              double duration,
                              double thrust,
                              double isp,
                              Vector3D direction)

Simple constructor for a constant direction and constant thrust.

It uses the propulsion model BasicConstantThrustPropulsionModel and the maneuver triggers DateBasedManeuverTriggers

Calling this constructor is equivalent to call ConstantThrustManeuver(date, duration, thrust, isp, direction, ""), hence not using any prefix for the parameters drivers names.

Parameters:

date - maneuver date

duration - the duration of the thrust (s) (if negative, the date is considered to be the stop date)

thrust - the thrust force (N)

isp - engine specific impulse (s)

direction - the acceleration direction in satellite frame.

ConstantThrustManeuver

public ConstantThrustManeuver(AbsoluteDate date,
                              double duration,
                              double thrust,
                              double isp,
                              AttitudeProvider attitudeOverride,
                              Vector3D direction)

Simple constructor for a constant direction and constant thrust.

It uses the propulsion model BasicConstantThrustPropulsionModel and the maneuver triggers DateBasedManeuverTriggers

Calling this constructor is equivalent to call ConstantThrustManeuver(date, duration, thrust, isp, direction, ""), hence not using any prefix for the parameters drivers names.

Parameters:

date - maneuver date

duration - the duration of the thrust (s) (if negative, the date is considered to be the stop date)

thrust - the thrust force (N)

isp - engine specific impulse (s)

attitudeOverride - the attitude provider to use for the maneuver, or null if the attitude from the propagator should be used

direction - the acceleration direction in satellite frame.

Since:

9.2

ConstantThrustManeuver

public ConstantThrustManeuver(AbsoluteDate date,
                              double duration,
                              double thrust,
                              double isp,
                              Vector3D direction,
                              String name)

Simple constructor for a constant direction and constant thrust.

It uses the propulsion model BasicConstantThrustPropulsionModel and the maneuver triggers DateBasedManeuverTriggers

The name of the maneuver is used to distinguish the parameter drivers. A typical use case is to use something like "1A-" or "2B-" as a prefix corresponding to the name of the thruster to use, so separate parameters can be adjusted for the different thrusters involved during an orbit determination where maneuvers parameters are estimated.

Parameters:

date - maneuver date

duration - the duration of the thrust (s) (if negative, the date is considered to be the stop date)

thrust - the thrust force (N)

isp - engine specific impulse (s)

direction - the acceleration direction in satellite frame

name - name of the maneuver, used as a prefix for the parameters drivers

Since:

9.0

ConstantThrustManeuver

public ConstantThrustManeuver(AbsoluteDate date,
                              double duration,
                              double thrust,
                              double isp,
                              AttitudeProvider attitudeOverride,
                              Vector3D direction,
                              String name)

Simple constructor for a constant direction and constant thrust.

It uses the propulsion model BasicConstantThrustPropulsionModel and the maneuver triggers DateBasedManeuverTriggers

The name of the maneuver is used to distinguish the parameter drivers. A typical use case is to use something like "1A-" or "2B-" as a prefix corresponding to the name of the thruster to use, so separate parameters can be adjusted for the different thrusters involved during an orbit determination where maneuvers parameters are estimated.

Parameters:

date - maneuver date

duration - the duration of the thrust (s) (if negative, the date is considered to be the stop date)

thrust - the thrust force (N)

isp - engine specific impulse (s)

attitudeOverride - the attitude provider to use for the maneuver, or null if the attitude from the propagator should be used

direction - the acceleration direction in satellite frame

name - name of the maneuver, used as a prefix for the parameters drivers

Since:

9.2

ConstantThrustManeuver

public ConstantThrustManeuver(AbsoluteDate date,
                              double duration,
                              AttitudeProvider attitudeOverride,
                              AbstractConstantThrustPropulsionModel constantThrustPropulsionModel)

Simple constructor for a constant direction and constant thrust.

It uses an AbstractConstantThrustPropulsionModel and the maneuver triggers DateBasedManeuverTriggers

The names of the maneuver (and thus its parameter drivers) are extracted from the propulsion model.

Parameters:

date - maneuver date

duration - the duration of the thrust (s) (if negative, the date is considered to be the stop date)

attitudeOverride - the attitude provider to use for the maneuver, or null if the attitude from the propagator should be used

constantThrustPropulsionModel - user-defined constant thrust propulsion model

ConstantThrustManeuver

public ConstantThrustManeuver(AttitudeProvider attitudeOverride,
                              DateBasedManeuverTriggers dateBasedManeuverTriggers,
                              AbstractConstantThrustPropulsionModel constantThrustPropulsionModel)

Simple constructor for a constant direction and constant thrust.

It uses an AbstractConstantThrustPropulsionModel and the maneuver triggers DateBasedManeuverTriggers

The names of the maneuver (and thus its parameter drivers) are extracted from the propulsion model or the maneuver triggers. Propulsion model name is evaluated first, if it isn't empty, it becomes the name of the maneuver. In that case the name in the maneuver triggers should be the same or empty, otherwise this could be misleading when retrieving estimated parameters by their names.

Parameters:

attitudeOverride - the attitude provider to use for the maneuver, or null if the attitude from the propagator should be used

dateBasedManeuverTriggers - user-defined maneuver triggers object based on a start and end date

constantThrustPropulsionModel - user-defined constant thrust propulsion model

Method Detail

getThrustVector

public Vector3D getThrustVector()

Get the thrust vector (N) in S/C frame.

Returns:

thrust vector (N) in S/C frame.

getThrust

public double getThrust()

Get the thrust.

Returns:

thrust force (N).

getISP

public double getISP()

Get the specific impulse.

Returns:

specific impulse (s).

getFlowRate

public double getFlowRate()

Get the flow rate.

Returns:

flow rate (negative, kg/s).

getDirection

public Vector3D getDirection()

Get the direction.

Returns:

the direction

Since:

9.2

getStartDate

public AbsoluteDate getStartDate()

Get the start date.

Returns:

the start date

Since:

9.2

getEndDate

public AbsoluteDate getEndDate()

Get the end date.

Returns:

the end date

Since:

9.2

getDuration

public double getDuration()

Get the duration of the maneuver (s). duration = endDate - startDate

Returns:

the duration of the maneuver (s)

Since:

9.2

isFiring

public boolean isFiring(SpacecraftState s)

Check if maneuvering is on.

Parameters:

s - current state

Returns:

true if maneuver is on at this state

Since:

10.1

isFiring

public <T extends CalculusFieldElement<T>> boolean isFiring(FieldSpacecraftState<T> s)

Check if maneuvering is on.

Type Parameters:

T - type of the field elements

Parameters:

s - current state

Returns:

true if maneuver is on at this state

Since:

10.1

isFiring

public boolean isFiring(AbsoluteDate date)

Check if maneuvering is on.

Parameters:

date - current date

Returns:

true if maneuver is on at this date

Since:

10.1