agi.foundation.access

(agi.foundation.core-2024r2.jar)

Class AccessConstraintSampling

java.lang.Object

agi.foundation.access.AccessConstraintSampling

public final class AccessConstraintSampling
extends Object

Contains static methods that can be useful to a constraint in determining the size of the next sampling step.

Field Summary

Fields

Modifier and Type	Field and Description
static double	StandardMaximumMotionPerSample A common value for the maximum angular motion between two objects that is allowed when choosing the next time at which to sample an Access constraint.

Method Summary

Modifier and Type	Method and Description
static JulianDate	getNextStepFromRelativeMotion(JulianDate epoch, Motion1<Cartesian> relativeMotion, double maximumAngularMotion) Computes an appropriate next sample step based on the relative motion between the two platforms involved in the Access computation and a maximum relative motion per step.
static Evaluator<JulianDate>	getNextStepFromRelativeMotionEvaluator(ILinkConstraint constraint, double maximumAngularMotion, EvaluatorGroup group) Gets an evaluator that determines the next time at which to sample a constraint function based on the relative motion between two objects and a maximum relative motion per step.
static Evaluator<JulianDate>	getNextStepFromRelativeMotionEvaluator(IServiceProvider observer, IServiceProvider target, double maximumAngularMotion, EvaluatorGroup group) Gets an evaluator that determines the next time at which to sample a constraint function based on the relative motion between two objects and a maximum relative motion per step.
static Evaluator<JulianDate>	getNextStepFromRelativeMotionEvaluator(ReferenceFrame observer, Point target, double maximumAngularMotion, EvaluatorGroup group) Gets an evaluator that determines the next time at which to sample a constraint function based on the relative motion between two objects and a maximum relative motion per step.

Methods inherited from class java.lang.Object

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

Field Detail

StandardMaximumMotionPerSample

public static final double StandardMaximumMotionPerSample

A common value for the maximum angular motion between two objects that is allowed when choosing the next time at which to sample an Access constraint. This corresponds to about 20 degrees.

See Also:

Constant Field Values

Method Detail

getNextStepFromRelativeMotionEvaluator

@Nonnull
public static Evaluator<JulianDate> getNextStepFromRelativeMotionEvaluator(@Nonnull
                                                                                     ILinkConstraint constraint,
                                                                                     double maximumAngularMotion,
                                                                                     @Nonnull
                                                                                     EvaluatorGroup group)

Gets an evaluator that determines the next time at which to sample a constraint function based on the relative motion between two objects and a maximum relative motion per step.

In order to determine the next sample time, this evaluator requires that the angular velocity of the target relative to the observer be available. If it is not, the evaluator will return the input time as the next step, indicating that a default step should be taken.

Parameters:

constraint - The constraint from which the two objects (the observer and target) should be determined.

maximumAngularMotion - The maximum angular motion allowed, in radians.

group - The group with which to associate the new evaluator. By grouping evaluators that are often evaluated at the same Julian dates, common computations can be performed only once for the entire group instead of multiple times for each evaluator.

Returns:

The evaluator.

Throws:

ServiceNotAvailableException -

Thrown when any of the following conditions are met:

• The constraint's ConstrainedLink (get / set) does not provide ILinkService.
• The end of the link that is identified as the observer does not provide IKinematicStateService.
• The end of the link that is identified as the target does not provide ILocationPointService.

PropertyInvalidException -

Thrown when any of the following conditions are met:

• The constraint's ConstrainedLink (get / set) property is null.
• The link's Transmitter (get) property is null.
• The link's Receiver (get) property is null.
• The end of the link which is identified as the observer has a null ReferenceFrame (get) property.
• The end of the link which is identified as the target has a null LocationPoint (get) property.

getNextStepFromRelativeMotionEvaluator

@Nonnull
public static Evaluator<JulianDate> getNextStepFromRelativeMotionEvaluator(@Nonnull
                                                                                     IServiceProvider observer,
                                                                                     @Nonnull
                                                                                     IServiceProvider target,
                                                                                     double maximumAngularMotion,
                                                                                     @Nonnull
                                                                                     EvaluatorGroup group)

Gets an evaluator that determines the next time at which to sample a constraint function based on the relative motion between two objects and a maximum relative motion per step.

In order to determine the next sample time, this evaluator requires that the angular velocity of the target relative to the observer be available. If it is not, the evaluator will return the input time as the next step, indicating that a default step should be taken.

Parameters:

observer - The object that is observing the motion of the target.

target - The object whose motion is being observed.

maximumAngularMotion - The maximum angular motion allowed, in radians.

group - The group with which to associate the new evaluator. By grouping evaluators that are often evaluated at the same Julian dates, common computations can be performed only once for the entire group instead of multiple times for each evaluator.

Returns:

The evaluator.

Throws:

ServiceNotAvailableException - The observer does not provide IKinematicStateService or the target does not provide ILocationPointService.

PropertyInvalidException - The observer object's IKinematicStateService has a null ReferenceFrame (get) property or the target object's ILocationPointService has a null LocationPoint (get) property.

getNextStepFromRelativeMotionEvaluator

@Nonnull
public static Evaluator<JulianDate> getNextStepFromRelativeMotionEvaluator(@Nonnull
                                                                                     ReferenceFrame observer,
                                                                                     @Nonnull
                                                                                     Point target,
                                                                                     double maximumAngularMotion,
                                                                                     @Nonnull
                                                                                     EvaluatorGroup group)

Gets an evaluator that determines the next time at which to sample a constraint function based on the relative motion between two objects and a maximum relative motion per step.

In order to determine the next sample time, this evaluator requires that the angular velocity of the target relative to the observer be available. If it is not, the evaluator will return the input time as the next step, indicating that a default step should be taken.

Parameters:

observer - The reference frame from which the motion of the target is observed.

target - The point describing the motion of the object that is being observed.

maximumAngularMotion - The maximum angular motion allowed, in radians.

group - The group with which to associate the new evaluator. By grouping evaluators that are often evaluated at the same Julian dates, common computations can be performed only once for the entire group instead of multiple times for each evaluator.

Returns:

The evaluator.

getNextStepFromRelativeMotion

@Nonnull
public static JulianDate getNextStepFromRelativeMotion(@Nonnull
                                                                 JulianDate epoch,
                                                                 @Nonnull
                                                                 Motion1<Cartesian> relativeMotion,
                                                                 double maximumAngularMotion)

Computes an appropriate next sample step based on the relative motion between the two platforms involved in the Access computation and a maximum relative motion per step.

Parameters:

epoch - The epoch from which the next sample is to be determined.

relativeMotion - The relative motion between the platforms.

maximumAngularMotion - The maximum angular motion allowed, in radians.

Returns:

The Julian date at which the next sample should be evaluated.