org.orekit.bodies
public class OneAxisEllipsoid extends Object implements BodyShape
One-axis ellipsoids is a good approximate model for most planet-size and larger natural bodies. It is the equilibrium shape reached by a fluid body under its own gravity field when it rotates. The symmetry axis is the rotation or polar axis.
Constructor and Description |
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OneAxisEllipsoid(double ae,
double f,
Frame bodyFrame)
Simple constructor.
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Modifier and Type | Method and Description |
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Frame |
getBodyFrame()
Get the body frame related to body shape.
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double |
getEquatorialRadius()
Get the equatorial radius of the body.
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double |
getFlattening()
Get the flattening of the body: f = (a-b)/a.
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GeodeticPoint |
getIntersectionPoint(Line line,
Vector3D close,
Frame frame,
AbsoluteDate date)
Get the intersection point of a line with the surface of the body.
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void |
setAngularThreshold(double angularThreshold)
Set the angular convergence threshold.
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void |
setCloseApproachThreshold(double closeApproachThreshold)
Deprecated.
as of 6.1, this threshold is not used anymore
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Vector3D |
transform(GeodeticPoint point)
Transform a surface-relative point to a cartesian point.
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GeodeticPoint |
transform(Vector3D point,
Frame frame,
AbsoluteDate date)
Transform a cartesian point to a surface-relative point.
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public OneAxisEllipsoid(double ae, double f, Frame bodyFrame)
The following table provides conventional parameters for global Earth models:
model | ae (m) | f |
---|---|---|
GRS 80 | 6378137.0 | 1.0 / 298.257222101 |
WGS84 | 6378137.0 | 1.0 / 298.257223563 |
ae
- equatorial radiusf
- the flattening (f = (a-b)/a)bodyFrame
- body frame related to body shapeFramesFactory.getITRF(org.orekit.utils.IERSConventions, boolean)
@Deprecated public void setCloseApproachThreshold(double closeApproachThreshold)
closeApproachThreshold
- close approach threshold (no unit)public void setAngularThreshold(double angularThreshold)
The angular threshold is used both to identify points close to
the ellipse axes and as the convergence threshold used to
stop the iterations in the transform(Vector3D, Frame,
AbsoluteDate)
method.
If this method is not called, the default value is set to 10-12.
angularThreshold
- angular convergence threshold (rad)public double getEquatorialRadius()
public double getFlattening()
public Frame getBodyFrame()
getBodyFrame
in interface BodyShape
public GeodeticPoint getIntersectionPoint(Line line, Vector3D close, Frame frame, AbsoluteDate date) throws OrekitException
A line may have several intersection points with a closed surface (we consider the one point case as a degenerated two points case). The close parameter is used to select which of these points should be returned. The selected point is the one that is closest to the close point.
getIntersectionPoint
in interface BodyShape
line
- test line (may intersect the body or not)close
- point used for intersections selectionframe
- frame in which line is expresseddate
- date of the line in given frameOrekitException
- if line cannot be converted to body framepublic Vector3D transform(GeodeticPoint point)
public GeodeticPoint transform(Vector3D point, Frame frame, AbsoluteDate date) throws OrekitException
transform
in interface BodyShape
point
- cartesian pointframe
- frame in which cartesian point is expresseddate
- date of the point in given frameOrekitException
- if point cannot be converted to body frameCopyright © 2002–2015 CS Syst?mes d'Information. All rights reserved.