Transform (patrius 4.3 API)

java.lang.Object
- fr.cnes.sirius.patrius.frames.transformations.Transform

All Implemented Interfaces:: TimeInterpolable<Transform>, TimeShiftable<Transform>, TimeStamped, Serializable

public class Transform
extends Object
implements TimeStamped, TimeShiftable<Transform>, TimeInterpolable<Transform>, Serializable

Transformation class in three dimensional space.

This class represents the transformation engine between frames. It is used both to define the relationship between each frame and its parent frame and to gather all individual transforms into one operation when converting between frames far away from each other.

A Transform object contain the position, velocity and orientation vectors that describe the "destination" frames in the "origin" one. This means that, defining X_ref=(1,0,0) in the origin frame, the vector X_destination (X axis of the destination frame, still expressed in the reference frame) is obtained by : rotation.applyTo(X_ref).

Instances of this class are guaranteed to be immutable.

Example

 
 1 ) Example of translation from R_A to R_B:
 We want to transform the PVCoordinates PV_A to PV_B.
 
 With :  PV_A = ({1, 0, 0} , {1, 0, 0} , {1, 0, 0});
 and  :  PV_B = ({0, 0, 0} , {0, 0, 0} , {0, 0, 0});
 
 The transform to apply then is defined as follows :
 
 Vector3D translation = new Vector3D(1,0,0);
 Vector3D velocity = new Vector3D(1,0,0);
 Vector3D acc = new Vector3D(1,0,0);
 
 Transform R1toR2 = new Transform(date, translation, Velocity, acc);
 
 PV_B = R1toR2.transformPVCoordinates(PV_A);
 
 
 2 ) Example of rotation from R_A to R_B:
 We want to transform the PVCoordinates PV_A to PV_B.
 
 With :  PV_A = ({0, 1, 0}, {-2, 1, 0});
 and  :  PV_B = ({1, 0, 0}, {1, 0, 0});
 
 The transform to apply then is defined as follows :
 
 Rotation rotation = new Rotation(Vector3D.PLUS_K, FastMath.PI / 2);
 Vector3D rotationRate = new Vector3D(0, 0, 2);
 
 Transform R1toR2 = new Transform(date, rotation, rotationRate);
 
 PV_B = R1toR2.transformPVCoordinates(PV_A);

Author:: Luc Maisonobe, Fabien Maussion
See Also:: Serialized Form

Field Summary

Fields
Modifier and Type Field and Description

static Transform IDENTITY
Identity transform.

Fields
Modifier and Type	Field and Description
`static Transform`	`IDENTITY` Identity transform.

Constructor Summary

Constructors
Constructor and Description
`Transform(AbsoluteDate dateIn, AngularCoordinates angularIn)` Build a rotation transform.
`Transform(AbsoluteDate dateIn, PVCoordinates cartesianIn)` Build a translation transform, with its first time derivative.
`Transform(AbsoluteDate dateIn, PVCoordinates cartesianIn, AngularCoordinates angularIn)` Build a transform from its primitive operations.
`Transform(AbsoluteDate dateIn, Rotation rotation)` Build a rotation transform.
`Transform(AbsoluteDate dateIn, Rotation rotation, Vector3D rotationRate)` Build a rotation transform.
`Transform(AbsoluteDate dateIn, Rotation rotation, Vector3D rotationRate, Vector3D rotationAcceleration)` Build a rotation transform.
`Transform(AbsoluteDate dateIn, Transform first, Transform second)` Build a transform by combining two existing ones without computing spin derivatives.
`Transform(AbsoluteDate dateIn, Transform first, Transform second, boolean computeSpinDerivatives)` Build a transform by combining two existing ones.
`Transform(AbsoluteDate dateIn, Vector3D translation)` Build a translation transform.
`Transform(AbsoluteDate dateIn, Vector3D translation, Vector3D velocity)` Build a translation transform, with its first time derivative.
`Transform(AbsoluteDate dateIn, Vector3D translation, Vector3D velocity, Vector3D acceleration)` Build a translation transform, with its first and second time derivatives.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Transform`	`freeze()` Get a freezed transform.
`Vector3D`	`getAcceleration()` Get the second time derivative of the translation.
`AngularCoordinates`	`getAngular()` Get the orientation and rotation rate of the "destination" frame in the "origin" one.
`PVCoordinates`	`getCartesian()` Get the position and velocity of the "destination" frame in the "origin" one.
`AbsoluteDate`	`getDate()` Get the date.
`Transform`	`getInverse()` Get the inverse transform of the instance.
`Transform`	`getInverse(boolean computeSpinDerivatives)` Get the inverse transform of the instance.
`void`	`getJacobian(double[][] jacobian)` Compute the Jacobian of the `transformPVCoordinates(PVCoordinates)` method of the transform.
`Rotation`	`getRotation()` Get the orientation of the "destination" frame in the "origin" one.
`Vector3D`	`getRotationAcceleration()` Get the second time derivative of the rotation.
`Vector3D`	`getRotationRate()` Get the rotation rate of the "destination" frame in the "origin" one.
`Vector3D`	`getTranslation()` Get the position of the "destination" frame in the "origin" one.
`Vector3D`	`getVelocity()` Get the velocity of the "destination" frame in the "origin" one.
`static Transform`	`interpolate(AbsoluteDate date, boolean useVelocities, boolean useRotationRates, Collection<Transform> sample)` Interpolate a transform from a sample set of existing transforms.
`static Transform`	`interpolate(AbsoluteDate date, boolean useVelocities, boolean useRotationRates, Collection<Transform> sample, boolean computeSpinDerivative)` Interpolate a transform from a sample set of existing transforms.
`Transform`	`interpolate(AbsoluteDate interpolationDate, Collection<Transform> sample)` Get an interpolated instance.
`Transform`	`interpolate(AbsoluteDate interpolationDate, Collection<Transform> sample, boolean computeSpinDerivative)` Get an interpolated instance.
`Transform`	`shiftedBy(double dt)` Get a time-shifted instance.
`Transform`	`shiftedBy(double dt, boolean computeSpinDerivative)` Get a time-shifted instance.
`Line`	`transformLine(Line line)` Transform a line from an algebraic point of view.
`Vector3D`	`transformPosition(Vector3D position)` Transform a position vector (including translation effects).
`PVCoordinates`	`transformPVCoordinates(PVCoordinates pv)` Transform `PVCoordinates` including kinematic effects from an algebraic point of view.
`TimeStampedPVCoordinates`	`transformPVCoordinates(TimeStampedPVCoordinates pv)` Transform `TimeStampedPVCoordinates` including kinematic effects.
`Vector3D`	`transformVector(Vector3D vector)` Transform a vector (ignoring translation effects).
`Wrench`	`transformWrench(Wrench wrench)` Transform a wrench (ignoring translation effects).

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - IDENTITY
```
public static final Transform IDENTITY
```
    Identity transform.
- Constructor Detail
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Vector3D translation)
```
    Build a translation transform.
    
    Parameters:
    
    dateIn - date of the transform
    
    translation - the position of the "destination" frame expressed in the "origin" one
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Rotation rotation)
```
    Build a rotation transform.
    
    Parameters:
    
    dateIn - date of the transform
    
    rotation - the orientation of the "destination" frame expressed in the "origin" one
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Vector3D translation,
                 Vector3D velocity)
```
    Build a translation transform, with its first time derivative.
    
    Parameters:
    
    dateIn - date of the transform
    
    translation - the position of the "destination" frame expressed in the "origin" one
    
    velocity - the velocity of the "destination" frame expressed in the "origin" one
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Vector3D translation,
                 Vector3D velocity,
                 Vector3D acceleration)
```
    Build a translation transform, with its first and second time derivatives.
    
    Parameters:
    
    dateIn - date of the transform
    
    translation - the position of the "destination" frame expressed in the "origin" one
    
    velocity - the velocity of the "destination" frame expressed in the "origin" one
    
    acceleration - the acceleration of the "destination" frame expressed in the "origin" one
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 PVCoordinates cartesianIn)
```
    Build a translation transform, with its first time derivative.
    
    Parameters:
    
    dateIn - date of the transform
    
    cartesianIn - position and velocity of the "destination" frame expressed in the "origin" one
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Rotation rotation,
                 Vector3D rotationRate)
```
    Build a rotation transform.
    
    Parameters:
    
    dateIn - date of the transform
    
    rotation - the orientation of the "destination" frame expressed in the "origin" one
    
    rotationRate - the rotation rate of the "destination" frame in the "origin" one, expressed in the "destination" frame
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Rotation rotation,
                 Vector3D rotationRate,
                 Vector3D rotationAcceleration)
```
    Build a rotation transform.
    
    Parameters:
    
    dateIn - date of the transform
    
    rotation - the orientation of the "destination" frame expressed in the "origin" one
    
    rotationRate - the rotation rate of the "destination" frame in the "origin" one, expressed in the "destination" frame
    
    rotationAcceleration - the axis of the instant rotation expressed in the new frame. (norm representing angular rate)
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 AngularCoordinates angularIn)
```
    Build a rotation transform.
    
    Parameters:
    
    dateIn - date of the transform
    
    angularIn - AngularCoordinates of the "destination" frame in the "origin" one
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Transform first,
                 Transform second)
```
    Build a transform by combining two existing ones without computing spin derivatives.
    Warning: spin derivative is not computed.
    
    Parameters:
    
    dateIn - date of the transform
    
    first - first transform applied
    
    second - second transform applied
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 Transform first,
                 Transform second,
                 boolean computeSpinDerivatives)
```
    Build a transform by combining two existing ones.
    Note that the dates of the two existing transformed are ignored, and the combined transform date is set to the date supplied in this constructor without any attempt to shift the raw transforms. This is a design choice allowing user full control of the combination.
    
    Parameters:
    
    dateIn - date of the transform
    
    first - first transform applied
    
    second - second transform applied
    
    computeSpinDerivatives - true if spin derivatives should be computed. If not, spin derivative is set to null
  - Transform
```
public Transform(AbsoluteDate dateIn,
                 PVCoordinates cartesianIn,
                 AngularCoordinates angularIn)
```
    Build a transform from its primitive operations.
    
    Parameters:
    
    dateIn - date of the transform
    
    cartesianIn - position and velocity of the "destination" frame expressed in the "origin" one
    
    angularIn - AngularCoordinates of the "destination" frame in the "origin" one
- Method Detail
  - getDate
```
public AbsoluteDate getDate()
```
    Get the date.
    
    Specified by:
    
    getDate in interface TimeStamped
    
    Returns:
    
    date attached to the object
  - shiftedBy
```
public Transform shiftedBy(double dt)
```
    Get a time-shifted instance.
    Warning: spin derivative is not computed.
    
    Specified by:
    
    shiftedBy in interface TimeShiftable<Transform>
    
    Parameters:
    
    dt - time shift in seconds
    
    Returns:
    
    a new instance, shifted with respect to instance (which is not changed)
  - shiftedBy
```
public Transform shiftedBy(double dt,
                           boolean computeSpinDerivative)
```
    Get a time-shifted instance.
    
    Parameters:
    
    dt - time shift in seconds
    
    computeSpinDerivative - true if spin derivatives should be computed. If not, spin derivative is set to null
    
    Returns:
    
    a new instance, shifted with respect to instance (which is not changed)
  - interpolate
```
public Transform interpolate(AbsoluteDate interpolationDate,
                             Collection<Transform> sample)
                      throws PatriusException
```
    Get an interpolated instance.
    Note that the state of the current instance may not be used in the interpolation process, only its type and non interpolable fields are used (for example central attraction coefficient or frame when interpolating orbits). The interpolable fields taken into account are taken only from the states of the sample points. So if the state of the instance must be used, the instance should be included in the sample points.
    
    Calling this method is equivalent to call interpolate(AbsoluteDate, boolean, boolean, Collection) with both useVelocities and useRotationRates set to true.
    
    Warning: spin derivative is not computed.
    
    Specified by:
    
    interpolate in interface TimeInterpolable<Transform>
    
    Parameters:
    
    interpolationDate - interpolation date
    
    sample - sample points on which interpolation should be done
    
    Returns:
    
    a new instance, interpolated at specified date
    
    Throws:
    
    PatriusException - if the sample points are inconsistent
  - interpolate
```
public Transform interpolate(AbsoluteDate interpolationDate,
                             Collection<Transform> sample,
                             boolean computeSpinDerivative)
                      throws PatriusException
```
    Get an interpolated instance.
    Note that the state of the current instance may not be used in the interpolation process, only its type and non interpolable fields are used (for example central attraction coefficient or frame when interpolating orbits). The interpolable fields taken into account are taken only from the states of the sample points. So if the state of the instance must be used, the instance should be included in the sample points.
    
    Calling this method is equivalent to call interpolate(AbsoluteDate, boolean, boolean, Collection) with both useVelocities and useRotationRates set to true.
    
    Parameters:
    
    interpolationDate - interpolation date
    
    sample - sample points on which interpolation should be done
    
    computeSpinDerivative - true if spin derivatives should be computed. If not, spin derivative is set to null
    
    Returns:
    
    a new instance, interpolated at specified date
    
    Throws:
    
    PatriusException - if the sample points are inconsistent
  - interpolate
```
public static Transform interpolate(AbsoluteDate date,
                                    boolean useVelocities,
                                    boolean useRotationRates,
                                    Collection<Transform> sample)
                             throws PatriusException
```
    Interpolate a transform from a sample set of existing transforms.
    Note that even if first time derivatives (velocities and rotation rates) from sample can be ignored, the interpolated instance always includes interpolated derivatives. This feature can be used explicitly to compute these derivatives when it would be too complex to compute them from an analytical formula: just compute a few sample points from the explicit formula and set the derivatives to zero in these sample points, then use interpolation to add derivatives consistent with the positions and rotations.
    
    Warning: spin derivative is not computed.
    
    Parameters:
    
    date - interpolation date
    
    useVelocities - if true, use sample transforms velocities, otherwise ignore them and use only positions
    
    useRotationRates - if true, use sample points rotation rates, otherwise ignore them and use only rotations
    
    sample - sample points on which interpolation should be done
    
    Returns:
    
    a new instance, interpolated at specified date
    
    Throws:
    
    PatriusException - OrekitException if the number of point is too small for interpolating
  - interpolate
```
public static Transform interpolate(AbsoluteDate date,
                                    boolean useVelocities,
                                    boolean useRotationRates,
                                    Collection<Transform> sample,
                                    boolean computeSpinDerivative)
                             throws PatriusException
```
    Interpolate a transform from a sample set of existing transforms.
    Note that even if first time derivatives (velocities and rotation rates) from sample can be ignored, the interpolated instance always includes interpolated derivatives. This feature can be used explicitly to compute these derivatives when it would be too complex to compute them from an analytical formula: just compute a few sample points from the explicit formula and set the derivatives to zero in these sample points, then use interpolation to add derivatives consistent with the positions and rotations.
    
    Parameters:
    
    date - interpolation date
    
    useVelocities - if true, use sample transforms velocities, otherwise ignore them and use only positions
    
    useRotationRates - if true, use sample points rotation rates, otherwise ignore them and use only rotations
    
    sample - sample points on which interpolation should be done
    
    computeSpinDerivative - true if spin derivatives should be computed. If not, spin derivative is set to null
    
    Returns:
    
    a new instance, interpolated at specified date
    
    Throws:
    
    PatriusException - if the number of point is too small for interpolating
  - getInverse
```
public Transform getInverse(boolean computeSpinDerivatives)
```
    Get the inverse transform of the instance.
    
    Parameters:
    
    computeSpinDerivatives - true if spin derivatives should be computed. If not, spin derivative is set to null
    
    Returns:
    
    inverse transform of the instance
  - getInverse
```
public Transform getInverse()
```
    Get the inverse transform of the instance.
    Warning: spin derivative is not computed.
    
    Returns:
    
    inverse transform of the instance
  - freeze
```
public Transform freeze()
```
    Get a freezed transform.
    This method creates a copy of the instance but frozen in time, i.e. with velocity, rotation rate, acceleration and rotation acceleration set to zero.
    
    Returns:
    
    a new transform, without any time-dependent parts
  - transformPosition
```
public Vector3D transformPosition(Vector3D position)
```
    Transform a position vector (including translation effects).
    
    Parameters:
    
    position - vector to transform
    
    Returns:
    
    transformed position
  - transformVector
```
public Vector3D transformVector(Vector3D vector)
```
    Transform a vector (ignoring translation effects).
    
    Parameters:
    
    vector - vector to transform
    
    Returns:
    
    transformed vector
  - transformWrench
```
public Wrench transformWrench(Wrench wrench)
```
    Transform a wrench (ignoring translation effects).
    
    Parameters:
    
    wrench - wrench to transform
    
    Returns:
    
    transformed wrench
  - transformLine
```
public Line transformLine(Line line)
```
    Transform a line from an algebraic point of view.
    
    Parameters:
    
    line - to transform
    
    Returns:
    
    transformed line
  - transformPVCoordinates
```
public PVCoordinates transformPVCoordinates(PVCoordinates pv)
```
    Transform PVCoordinates including kinematic effects from an algebraic point of view.
    
    Parameters:
    
    pv - the couple position-velocity to transform.
    
    Returns:
    
    transformed position/velocity
  - transformPVCoordinates
```
public TimeStampedPVCoordinates transformPVCoordinates(TimeStampedPVCoordinates pv)
```
    Transform TimeStampedPVCoordinates including kinematic effects.
    In order to allow the user more flexibility, this method does not check for consistency between the transform date and the time-stamped position-velocity date. The returned value will always have the same date as the input argument, regardless of the instance date.
    
    Parameters:
    
    pv - time-stamped position-velocity to transform.
    
    Returns:
    
    transformed time-stamped position-velocity
    
    Since:
    
    7.0
  - getJacobian
```
public void getJacobian(double[][] jacobian)
```
    Compute the Jacobian of the transformPVCoordinates(PVCoordinates) method of the transform.
    Element jacobian[i][j] is the derivative of Cartesian coordinate i of the transformed PVCoordinates with respect to Cartesian coordinate j of the input PVCoordinates in method transformPVCoordinates(PVCoordinates).
    
    This definition implies that if we define position-velocity coordinates
```
 PV₁ = transform.transformPVCoordinates(PV₀), then
 
```
    their differentials dPV₁ and dPV₀ will obey the following relation where J is the matrix computed by this method:
```
 dPV₁ = J × dPV₀
 
```
    Parameters:
    
    jacobian - placeholder 6x6 (or larger) matrix to be filled with the Jacobian, if matrix is larger than 6x6, only the 6x6 upper left corner will be modified
  - getCartesian
```
public PVCoordinates getCartesian()
```
    Get the position and velocity of the "destination" frame in the "origin" one.
    NB : A transform can be uniquely represented as an elementary translation followed by an elementary rotation. This method returns this unique elementary translation with its derivative.
    
    Returns:
    
    elementary cartesian part
    
    See Also:
    
    getTranslation(), getVelocity()
  - getTranslation
```
public Vector3D getTranslation()
```
    Get the position of the "destination" frame in the "origin" one.
    NB : A transform can be uniquely represented as an elementary translation followed by an elementary rotation. This method returns this unique elementary translation.
    
    Returns:
    
    elementary translation
    
    See Also:
    
    getCartesian(), getVelocity()
  - getVelocity
```
public Vector3D getVelocity()
```
    Get the velocity of the "destination" frame in the "origin" one.
    
    Returns:
    
    first time derivative of the translation
    
    See Also:
    
    getCartesian(), getTranslation()
  - getAcceleration
```
public Vector3D getAcceleration()
```
    Get the second time derivative of the translation.
    
    Returns:
    
    second time derivative of the translation
    
    See Also:
    
    getCartesian(), getTranslation(), getVelocity()
  - getAngular
```
public AngularCoordinates getAngular()
```
    Get the orientation and rotation rate of the "destination" frame in the "origin" one.
    NB : A transform can be uniquely represented as an elementary translation followed by an elementary rotation. This method returns this unique elementary rotation with its derivative.
    
    Returns:
    
    elementary angular coordinates
    
    See Also:
    
    getRotation(), getRotationRate()
  - getRotation
```
public Rotation getRotation()
```
    Get the orientation of the "destination" frame in the "origin" one.
    NB : A transform can be uniquely represented as an elementary translation followed by an elementary rotation. This method returns this unique elementary rotation.
    
    Returns:
    
    underlying elementary rotation
    
    See Also:
    
    getAngular(), getRotationRate()
  - getRotationRate
```
public Vector3D getRotationRate()
```
    Get the rotation rate of the "destination" frame in the "origin" one.
    The norm represents the angular rate.
    
    Returns:
    
    First time derivative of the rotation
    
    See Also:
    
    getAngular(), getRotation()
  - getRotationAcceleration
```
public Vector3D getRotationAcceleration()
```
    Get the second time derivative of the rotation. May be null
    
    Returns:
    
    Second time derivative of the rotation
    
    See Also:
    
    getAngular(), getRotation(), getRotationRate()

Class Transform

Example

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

IDENTITY

Constructor Detail

Transform

Transform

Transform

Transform

Transform

Transform

Transform

Transform

Transform

Transform

Transform

Method Detail

getDate

shiftedBy

shiftedBy

interpolate

interpolate

interpolate

interpolate

getInverse

getInverse

freeze

transformPosition

transformVector

transformWrench

transformLine

transformPVCoordinates

transformPVCoordinates

getJacobian

getCartesian

getTranslation

getVelocity

getAcceleration

getAngular

getRotation

getRotationRate

getRotationAcceleration