Class LatitudeCrossingDetector

  • All Implemented Interfaces:
    EventDetector

    public class LatitudeCrossingDetector
    extends AbstractDetector<LatitudeCrossingDetector>
    Detector for geographic latitude crossing.

    This detector identifies when a spacecraft crosses a fixed latitude with respect to a central body.

    Since:
    7.1
    Author:
    Luc Maisonobe
    • Constructor Detail

      • LatitudeCrossingDetector

        public LatitudeCrossingDetector​(double maxCheck,
                                        double threshold,
                                        OneAxisEllipsoid body,
                                        double latitude)
        Build a detector.
        Parameters:
        maxCheck - maximal checking interval (s)
        threshold - convergence threshold (s)
        body - body on which the latitude is defined
        latitude - latitude to be crossed
      • LatitudeCrossingDetector

        protected LatitudeCrossingDetector​(AdaptableInterval maxCheck,
                                           double threshold,
                                           int maxIter,
                                           EventHandler handler,
                                           OneAxisEllipsoid body,
                                           double latitude)
        Protected constructor with full parameters.

        This constructor is not public as users are expected to use the builder API with the various withXxx() methods to set up the instance in a readable manner without using a huge amount of parameters.

        Parameters:
        maxCheck - maximum checking interval
        threshold - convergence threshold (s)
        maxIter - maximum number of iterations in the event time search
        handler - event handler to call at event occurrences
        body - body on which the latitude is defined
        latitude - latitude to be crossed
    • Method Detail

      • create

        protected LatitudeCrossingDetector create​(AdaptableInterval newMaxCheck,
                                                  double newThreshold,
                                                  int newMaxIter,
                                                  EventHandler newHandler)
        Build a new instance.
        Specified by:
        create in class AbstractDetector<LatitudeCrossingDetector>
        Parameters:
        newMaxCheck - maximum checking interval (s)
        newThreshold - convergence threshold (s)
        newMaxIter - maximum number of iterations in the event time search
        newHandler - event handler to call at event occurrences
        Returns:
        a new instance of the appropriate sub-type
      • getBody

        public OneAxisEllipsoid getBody()
        Get the body on which the geographic zone is defined.
        Returns:
        body on which the geographic zone is defined
      • getLatitude

        public double getLatitude()
        Get the fixed latitude to be crossed (radians).
        Returns:
        fixed latitude to be crossed (radians)
      • g

        public double g​(SpacecraftState s)
        Compute the value of the detection function.

        The value is the spacecraft latitude minus the fixed latitude to be crossed. It is positive if the spacecraft is northward and negative if it is southward with respect to the fixed latitude.

        Parameters:
        s - the current state information: date, kinematics, attitude
        Returns:
        spacecraft latitude minus the fixed latitude to be crossed