Description

template<class Real = double>
class chrono::ChFrame< Real >

ChFrame: a class for coordinate systems in 3D space.

A 'frame' coordinate system has a translation and a rotation respect to a 'parent' coordinate system, usually the absolute (world) coordinates.

Differently from a simple ChCoordsys object, however, the ChFrame implements some optimizations because each ChFrame stores also a 3x3 rotation matrix, which can speed up coordinate transformations when a large amount of vectors must be transformed by the same coordinate frame.

Further info at the Coordinate transformations manual page.

#include <ChFrame.h>

Inheritance diagram for chrono::ChFrame< Real >:

[legend]

Public Member Functions
	ChFrame (const ChVector< Real > &mv=ChVector< Real >(0, 0, 0), const ChQuaternion< Real > &mq=ChQuaternion< Real >(1, 0, 0, 0))
	Default constructor, or construct from pos and rot (as a quaternion)

	ChFrame (const ChVector< Real > &mv, const ChMatrix33< Real > &ma)
	Construct from pos and rotation (as a 3x3 matrix)

	ChFrame (const ChCoordsys< Real > &mc)
	Construct from a coordsys.

	ChFrame (const ChVector< Real > &mv, const Real alpha, const ChVector< Real > &mu)
	Construct from position mv and rotation of angle alpha around unit vector mu.

	ChFrame (const ChFrame< Real > &other)
	Copy constructor, build from another frame.

ChFrame< Real > &	operator= (const ChFrame< Real > &other)
	Assignment operator: copy from another frame.

bool	operator== (const ChFrame< Real > &other) const
	Returns true for identical frames.

bool	operator!= (const ChFrame< Real > &other) const
	Returns true for different frames.

ChFrame< Real >	operator>> (const ChFrame< Real > &Fb) const
	The '>>' operator transforms a coordinate system, so transformations can be represented with this syntax: new_frame = old_frame >> tr_frame; For a sequence of transformations, i.e. More...

ChFrame< Real >	operator* (const ChFrame< Real > &Fb) const
	The '>>' operator transforms a vector, so transformations can be represented with this syntax: new_v = old_v >> tr_frame; For a sequence of transformations, i.e. More...

ChVector< Real >	operator* (const ChVector< Real > &V) const
	The '' operator transforms a vector, so transformations can be represented with this syntax: new_v = tr_frame old_v; For a sequence of transformations, i.e. More...

ChVector< Real >	operator/ (const ChVector< Real > &V) const
	The '/' is like the '*' operator (see), but uses the inverse transformation for A, in A/b. More...

ChFrame< Real > &	operator>>= (const ChFrame< Real > &T)
	Performs pre-multiplication of this frame by another frame, for example: A>>=T means A'=T*A ; or A'=A >> T.

ChFrame< Real > &	operator%= (const ChFrame< Real > &T)
	Performs pre-multiplication of this frame by another frame, for example: A%=T means A'=T*A ; or A'=A >> T Note: DEPRECATED, use >>= instead.

ChFrame< Real > &	operator*= (const ChFrame< Real > &T)
	Performs post-multiplication of this frame by another frame, for example: A=T means A'=AT ; or A'=T >> A.

ChFrame< Real > &	operator>>= (const ChVector< Real > &D)
	Performs pre-multiplication of this frame by a vector D, to 'move' by a displacement D:

ChFrame< Real > &	operator>>= (const ChQuaternion< Real > &R)
	Performs pre-multiplication of this frame by a quaternion R, to 'rotate' it by R:

ChFrame< Real > &	operator>>= (const ChCoordsys< Real > &F)
	Performs pre-multiplication of this frame by a ChCoordsys F, to transform it:

ChCoordsys< Real > &	GetCoord ()
	Return both current rotation and translation as a coordsystem object, with vector and quaternion.

const ChCoordsys< Real > &	GetCoord () const

ChVector< Real > &	GetPos ()
	Return the current translation as a 3d vector.

const ChVector< Real > &	GetPos () const

ChQuaternion< Real > &	GetRot ()
	Return the current rotation as a quaternion.

const ChQuaternion< Real > &	GetRot () const

ChMatrix33< Real > &	GetA ()
	Return the current rotation as a 3x3 matrix.

const ChMatrix33< Real > &	GetA () const

ChVector< Real >	GetRotAxis ()
	Get axis of finite rotation, in parent space.

Real	GetRotAngle ()
	Get angle of rotation about axis of finite rotation.

void	SetCoord (const ChCoordsys< Real > &mcoord)
	Impose both translation and rotation as a single ChCoordsys. More...

void	SetCoord (const ChVector< Real > &mv, const ChQuaternion< Real > &mq)
	Impose both translation and rotation. More...

void	SetRot (const ChQuaternion< Real > &mrot)
	Impose the rotation as a quaternion. More...

void	SetRot (const ChMatrix33< Real > &mA)
	Impose the rotation as a 3x3 matrix. More...

void	SetPos (const ChVector< Real > &mpos)
	Impose the translation.

void	ConcatenatePreTransformation (const ChFrame< Real > &T)
	Apply a transformation (rotation and translation) represented by another ChFrame T. More...

void	ConcatenatePostTransformation (const ChFrame< Real > &T)
	Apply a transformation (rotation and translation) represented by another ChFrame T in local coordinate. More...

void	Move (const ChVector< Real > &V)
	An easy way to move the frame by the amount specified by vector V, (assuming V expressed in parent coordinates)

void	Move (const ChCoordsys< Real > &VR)
	Apply both translation and rotation, assuming both expressed in parent coordinates, as a vector for translation and quaternion for rotation,.

ChVector< Real >	TransformLocalToParent (const ChVector< Real > &local) const
	This function transforms a point from the local frame coordinate system to the parent coordinate system. More...

ChVector< Real >	TransformPointLocalToParent (const ChVector< Real > &local) const

ChVector< Real >	TransformParentToLocal (const ChVector< Real > &parent) const
	This function transforms a point from the parent coordinate system to local frame coordinate system. More...

ChVector< Real >	TransformPointParentToLocal (const ChVector< Real > &parent) const

void	TransformLocalToParent (const ChFrame< Real > &local, ChFrame< Real > &parent) const
	This function transforms a frame from 'this' local coordinate system to parent frame coordinate system. More...

void	TransformParentToLocal (const ChFrame< Real > &parent, ChFrame< Real > &local) const
	This function transforms a frame from the parent coordinate system to 'this' local frame coordinate system. More...

ChVector< Real >	TransformDirectionParentToLocal (const ChVector< Real > &mdirection) const
	This function transforms a direction from 'this' local coordinate system to parent frame coordinate system. More...

ChVector< Real >	TransformDirectionLocalToParent (const ChVector< Real > &mdirection) const
	This function transforms a direction from the parent frame coordinate system to 'this' local coordinate system. More...

bool	Equals (const ChFrame< Real > &other) const
	Returns true if coordsys is identical to other coordsys.

bool	Equals (const ChFrame< Real > &other, Real tol) const
	Returns true if coordsys is equal to other coordsys, within a tolerance 'tol'.

void	Normalize ()
	Normalize the rotation, so that quaternion has unit length.

virtual void	SetIdentity ()
	Sets to no translation and no rotation.

virtual void	Invert ()
	The transformation is inverted in place. More...

ChFrame< Real >	GetInverse () const

virtual void	ArchiveOUT (ChArchiveOut &marchive)
	Method to allow serialization of transient data to archives.

virtual void	ArchiveIN (ChArchiveIn &marchive)
	Method to allow de-serialization of transient data from archives.

Public Attributes
ChCoordsys< Real >	coord
	Rotation and position, as vector+quaternion.

ChMatrix33< Real >	Amatrix
	3x3 orthogonal rotation matrix

Member Function Documentation

◆ ConcatenatePostTransformation()

template<class Real = double>

void chrono::ChFrame< Real >::ConcatenatePostTransformation ( const ChFrame< Real > & T )

inline

Apply a transformation (rotation and translation) represented by another ChFrame T in local coordinate.

This is equivalent to post-multiply this frame by the other frame T: this'= this * T; or this'= T >> this

◆ ConcatenatePreTransformation()

template<class Real = double>

void chrono::ChFrame< Real >::ConcatenatePreTransformation ( const ChFrame< Real > & T )

inline

Apply a transformation (rotation and translation) represented by another ChFrame T.

This is equivalent to pre-multiply this frame by the other frame T: this'= T * this; or this' = this >> T

◆ Invert()

template<class Real = double>

virtual void chrono::ChFrame< Real >::Invert ( )

inlinevirtual

The transformation is inverted in place.

That is if w=A*v, then A.Invert();v=A*w;

Reimplemented in chrono::ChFrameMoving< Real >, and chrono::ChFrameMoving< double >.

◆ operator*() [1/2]

template<class Real = double>

ChFrame<Real> chrono::ChFrame< Real >::operator* ( const ChFrame< Real > & Fb ) const

inline

The '>>' operator transforms a vector, so transformations can be represented with this syntax: new_v = old_v >> tr_frame; For a sequence of transformations, i.e.

a chain of coordinate systems, you can also write this (like you would do with a sequence of Denavitt-Hartemberg matrix multiplications, but in the opposite order...) new_v = old_v >> frame3to2 >> frame2to1 >> frame1to0; This operation is not commutative. The '*' operator transforms a coordinate system, so transformations can be represented with this syntax: new_frame = tr_frame * old_frame; For a sequence of transformations, i.e. a chain of coordinate systems, you can also write this (just like you would do with a sequence of Denavitt-Hartemberg matrix multiplications!) new_frame = frame1to0 * frame2to1 * frame3to2 * old_frame; This operation is not commutative. NOTE: since c++ operator execution is from left to right, in case of multiple transformations like w=A*B*C*v, the >> operator performs faster, like w=v>>C>>B>>A;

◆ operator*() [2/2]

template<class Real = double>

ChVector<Real> chrono::ChFrame< Real >::operator* ( const ChVector< Real > & V ) const

inline

The '*' operator transforms a vector, so transformations can be represented with this syntax: new_v = tr_frame * old_v; For a sequence of transformations, i.e.

a chain of coordinate systems, you can also write this (just like you would do with a sequence of Denavitt-Hartemberg matrix multiplications!) new_v = frame1to0 * frame2to1 * frame3to2 * old_v; This operation is not commutative. NOTE: since c++ operator execution is from left to right, in case of multiple transformations like w=A*B*C*v, the >> operator performs faster, like w=v>>C>>B>>A;

◆ operator/()

template<class Real = double>

ChVector<Real> chrono::ChFrame< Real >::operator/ ( const ChVector< Real > & V ) const

inline

The '/' is like the '*' operator (see), but uses the inverse transformation for A, in A/b.

(with A ChFrame, b ChVector) That is: c=A*b ; b=A/c;

◆ operator>>()

template<class Real = double>

ChFrame<Real> chrono::ChFrame< Real >::operator>> ( const ChFrame< Real > & Fb ) const

inline

The '>>' operator transforms a coordinate system, so transformations can be represented with this syntax: new_frame = old_frame >> tr_frame; For a sequence of transformations, i.e.

a chain of coordinate systems, you can also write this (like you would do with a sequence of Denavitt-Hartemberg matrix multiplications, but in the opposite order...) new_frame = old_frame >> frame3to2 >> frame2to1 >> frame1to0; This operation is not commutative.

◆ SetCoord() [1/2]

template<class Real = double>

void chrono::ChFrame< Real >::SetCoord ( const ChCoordsys< Real > & mcoord )

inline

Impose both translation and rotation as a single ChCoordsys.

Note: the quaternion part must be already normalized!

◆ SetCoord() [2/2]

template<class Real = double>

void chrono::ChFrame< Real >::SetCoord	(	const ChVector< Real > &	mv,
		const ChQuaternion< Real > &	mq
	)

inline

Impose both translation and rotation.

Note: the quaternion part must be already normalized!

◆ SetRot() [1/2]

template<class Real = double>

void chrono::ChFrame< Real >::SetRot ( const ChMatrix33< Real > & mA )

inline

Impose the rotation as a 3x3 matrix.

Note: the rotation matrix must be already orthogonal!

◆ SetRot() [2/2]

template<class Real = double>

void chrono::ChFrame< Real >::SetRot ( const ChQuaternion< Real > & mrot )

inline

Impose the rotation as a quaternion.

Note: the quaternion must be already normalized!

◆ TransformDirectionLocalToParent()

template<class Real = double>

ChVector<Real> chrono::ChFrame< Real >::TransformDirectionLocalToParent ( const ChVector< Real > & mdirection ) const

inline

This function transforms a direction from the parent frame coordinate system to 'this' local coordinate system.

Returns: The direction in parent frame coordinate

◆ TransformDirectionParentToLocal()

template<class Real = double>

ChVector<Real> chrono::ChFrame< Real >::TransformDirectionParentToLocal ( const ChVector< Real > & mdirection ) const

inline

This function transforms a direction from 'this' local coordinate system to parent frame coordinate system.

Returns: The direction in local frame coordinate

◆ TransformLocalToParent() [1/2]

template<class Real = double>

void chrono::ChFrame< Real >::TransformLocalToParent	(	const ChFrame< Real > &	local,
		ChFrame< Real > &	parent
	)		const

inline

This function transforms a frame from 'this' local coordinate system to parent frame coordinate system.

Returns: The frame in parent frame coordinate

Parameters

local	frame to transform, given in local frame coordinates
parent	transformed frame, in parent coordinates, will be stored here

◆ TransformLocalToParent() [2/2]

template<class Real = double>

ChVector<Real> chrono::ChFrame< Real >::TransformLocalToParent ( const ChVector< Real > & local ) const

inline

This function transforms a point from the local frame coordinate system to the parent coordinate system.

OPTIMIZED FOR SPEED. Since it will use the auxiliary rotation matrix of the ChFrame object, this function is about 50% faster than TransformParentToLocal of a ChCoordsys.

Returns: The point in parent coordinate

◆ TransformParentToLocal() [1/2]

template<class Real = double>

void chrono::ChFrame< Real >::TransformParentToLocal	(	const ChFrame< Real > &	parent,
		ChFrame< Real > &	local
	)		const

inline

This function transforms a frame from the parent coordinate system to 'this' local frame coordinate system.

Returns: The frame in local frame coordinate

Parameters

parent	frame to transform, given in parent coordinates
local	transformed frame, in local coordinates, will be stored here

◆ TransformParentToLocal() [2/2]

template<class Real = double>

ChVector<Real> chrono::ChFrame< Real >::TransformParentToLocal ( const ChVector< Real > & parent ) const

inline

This function transforms a point from the parent coordinate system to local frame coordinate system.

OPTIMIZED FOR SPEED. Since it will use the auxiliary rotation matrix of the ChFrame object, this function is about 50% faster than TransformParentToLocal method of a ChCoordsys.

Returns: The point in local frame coordinate

The documentation for this class was generated from the following file:

/builds/uwsbel/chrono/src/chrono/core/ChFrame.h

Description

template<class Real = double> class chrono::ChFrame< Real >

Public Member Functions

Public Attributes

Member Function Documentation

◆ ConcatenatePostTransformation()

◆ ConcatenatePreTransformation()

◆ Invert()

◆ operator*() [1/2]

◆ operator*() [2/2]

◆ operator/()

◆ operator>>()

◆ SetCoord() [1/2]

◆ SetCoord() [2/2]

◆ SetRot() [1/2]

◆ SetRot() [2/2]

◆ TransformDirectionLocalToParent()

◆ TransformDirectionParentToLocal()

◆ TransformLocalToParent() [1/2]

◆ TransformLocalToParent() [2/2]

◆ TransformParentToLocal() [1/2]

◆ TransformParentToLocal() [2/2]

template<class Real = double>
class chrono::ChFrame< Real >