public class LongitudeCrossingDetector extends AbstractDetector<LongitudeCrossingDetector>
This detector identifies when a spacecraft crosses a fixed longitude with respect to a central body.
DEFAULT_MAX_ITER, DEFAULT_MAXCHECK, DEFAULT_THRESHOLD
Constructor and Description |
---|
LongitudeCrossingDetector(double maxCheck,
double threshold,
OneAxisEllipsoid body,
double longitude)
Build a detector.
|
LongitudeCrossingDetector(OneAxisEllipsoid body,
double longitude)
Build a new detector.
|
Modifier and Type | Method and Description |
---|---|
protected LongitudeCrossingDetector |
create(double newMaxCheck,
double newThreshold,
int newMaxIter,
EventHandler<? super LongitudeCrossingDetector> newHandler)
Build a new instance.
|
double |
g(SpacecraftState s)
Compute the value of the detection function.
|
OneAxisEllipsoid |
getBody()
Get the body on which the geographic zone is defined.
|
double |
getLongitude()
Get the fixed longitude to be crossed (radians).
|
eventOccurred, getHandler, getMaxCheckInterval, getMaxIterationCount, getThreshold, init, isForward, resetState, withHandler, withMaxCheck, withMaxIter, withThreshold
public LongitudeCrossingDetector(OneAxisEllipsoid body, double longitude)
The new instance uses default values for maximal checking interval
(AbstractDetector.DEFAULT_MAXCHECK
) and convergence threshold (AbstractDetector.DEFAULT_THRESHOLD
).
body
- body on which the longitude is definedlongitude
- longitude to be crossedpublic LongitudeCrossingDetector(double maxCheck, double threshold, OneAxisEllipsoid body, double longitude)
maxCheck
- maximal checking interval (s)threshold
- convergence threshold (s)body
- body on which the longitude is definedlongitude
- longitude to be crossedprotected LongitudeCrossingDetector create(double newMaxCheck, double newThreshold, int newMaxIter, EventHandler<? super LongitudeCrossingDetector> newHandler)
create
in class AbstractDetector<LongitudeCrossingDetector>
newMaxCheck
- maximum checking interval (s)newThreshold
- convergence threshold (s)newMaxIter
- maximum number of iterations in the event time searchnewHandler
- event handler to call at event occurrencespublic OneAxisEllipsoid getBody()
public double getLongitude()
public double g(SpacecraftState s)
The value is the longitude difference between the spacecraft and the fixed
longitude to be crossed, with some sign tweaks to ensure continuity.
These tweaks imply the increasing
flag in events detection becomes
irrelevant here! As an example, the longitude of a prograde spacecraft
will always increase, but this g function will increase and decrease so it
will cross the zero value once per orbit, in increasing and decreasing
directions on alternate orbits. If eastwards and westwards crossing have to
be distinguished, the velocity direction has to be checked instead of looking
at the increasing
flag.
g
in interface EventDetector
g
in class AbstractDetector<LongitudeCrossingDetector>
s
- the current state information: date, kinematics, attitudeCopyright © 2002-2020 CS Group. All rights reserved.