Functions for transformation matrices
Package Frames.TransformationMatrices contains type definitions and functions to transform rotational frame quantities using transformation matrices.
In the table below an example is given for every function definition. The used variables have the following declaration:
Orientation T, T1, T2, T_rel, T_inv; Real[3] v1, v2, w1, w2, n_x, n_y, n_z, e, e_x, res_ori, phi; Real[6] res_equal; Real L, angle;
Function/type | Description |
---|---|
Orientation T; | New type defining an orientation object that describes the rotation of frame 1 into frame 2. |
der_Orientation der_T; | New type defining the first time derivative of Frames.Orientation. |
res_ori = orientationConstraint(T); | Return the constraints between the variables of an orientation object (shall be zero). |
w1 = angularVelocity1(T, der_T); | Return angular velocity resolved in frame 1 from
orientation object T and its derivative der_T. |
w2 = angularVelocity2(T, der_T); | Return angular velocity resolved in frame 2 from
orientation object T and its derivative der_T. |
v1 = resolve1(T,v2); | Transform vector v2 from frame 2 to frame 1. |
v2 = resolve2(T,v1); | Transform vector v1 from frame 1 to frame 2. |
[v1,w1] = multipleResolve1(T, [v2,w2]); | Transform several vectors from frame 2 to frame 1. |
[v2,w2] = multipleResolve2(T, [v1,w1]); | Transform several vectors from frame 1 to frame 2. |
D1 = resolveDyade1(T,D2); | Transform second order tensor D2 from frame 2 to frame 1. |
D2 = resolveDyade2(T,D1); | Transform second order tensor D1 from frame 1 to frame 2. |
T= nullRotation() | Return orientation object T that does not rotate a frame. |
T_inv = inverseRotation(T); | Return inverse orientation object. |
T_rel = relativeRotation(T1,T2); | Return relative orientation object from two absolute orientation objects. |
T2 = absoluteRotation(T1,T_rel); | Return absolute orientation object from another
absolute and a relative orientation object. |
T = planarRotation(e, angle); | Return orientation object of a planar rotation. |
angle = planarRotationAngle(e, v1, v2); | Return angle of a planar rotation, given the rotation axis and the representations of a vector in frame 1 and frame 2. |
T = axisRotation(i, angle); | Return orientation object T for rotation around axis i of frame 1. |
T = axesRotations(sequence, angles); | Return rotation object to rotate in sequence around 3 axes. Example: T = axesRotations({1,2,3},{90,45,-90}); |
angles = axesRotationsAngles(T, sequence); | Return the 3 angles to rotate in sequence around 3 axes to construct the given orientation object. |
phi = smallRotation(T); | Return rotation angles phi valid for a small rotation. |
T = from_nxy(n_x, n_y); | Return orientation object from n_x and n_y vectors. |
T = from_nxz(n_x, n_z); | Return orientation object from n_x and n_z vectors. |
R = from_T(T); | Return orientation object R from transformation matrix T. |
R = from_T_inv(T_inv); | Return orientation object R from inverse transformation matrix T_inv. |
T = from_Q(Q); | Return orientation object T from quaternion orientation object Q. |
T = to_T(R); | Return transformation matrix T from orientation object R. |
T_inv = to_T_inv(R); | Return inverse transformation matrix T_inv from orientation object R. |
Q = to_Q(T); | Return quaternion orientation object Q from orientation object T. |
exy = to_exy(T); | Return [e_x, e_y] matrix of an orientation object T, with e_x and e_y vectors of frame 2, resolved in frame 1. |
Extends from Modelica.Icons.FunctionsPackage (Icon for packages containing functions).
Name | Description |
---|---|
Orientation | Orientation type defining rotation from a frame 1 into a frame 2 with a transformation matrix |
der_Orientation | New type defining the first time derivative of Orientation |
orientationConstraint | Return residues of orientation constraints (shall be zero) |
angularVelocity1 | Return angular velocity resolved in frame 1 from orientation object and its derivative |
angularVelocity2 | Return angular velocity resolved in frame 2 from orientation object and its derivative |
resolve1 | Transform vector from frame 2 to frame 1 |
resolve2 | Transform vector from frame 1 to frame 2 |
multipleResolve1 | Transform several vectors from frame 2 to frame 1 |
multipleResolve2 | Transform several vectors from frame 1 to frame 2 |
resolveDyade1 | Transform second order tensor from frame 2 to frame 1 |
resolveDyade2 | Transform second order tensor from frame 1 to frame 2 |
nullRotation | Return orientation object that does not rotate a frame |
inverseRotation | Return inverse orientation object |
relativeRotation | Return relative orientation object |
absoluteRotation | Return absolute orientation object from another absolute and a relative orientation object |
planarRotation | Return orientation object of a planar rotation |
planarRotationAngle | Return angle of a planar rotation, given the rotation axis and the representations of a vector in frame 1 and frame 2 |
axisRotation | Return rotation object to rotate around one frame axis |
axesRotations | Return rotation object to rotate in sequence around 3 axes |
axesRotationsAngles | Return the 3 angles to rotate in sequence around 3 axes to construct the given orientation object |
smallRotation | Return rotation angles valid for a small rotation and optionally residues that should be zero |
from_nxy | Return orientation object from n_x and n_y vectors |
from_nxz | Return orientation object from n_x and n_z vectors |
from_T | Return orientation object R from transformation matrix T |
from_T_inv | Return orientation object R from inverse transformation matrix T_inv |
from_Q | Return orientation object T from quaternion orientation object Q |
to_T | Return transformation matrix T from orientation object R |
to_T_inv | Return inverse transformation matrix T_inv from orientation object R |
to_Q | Return quaternion orientation object Q from orientation object T |
to_vector | Map rotation object into vector |
to_exy | Map rotation object into e_x and e_y vectors of frame 2, resolved in frame 1 |
Orientation type defining rotation from a frame 1 into a frame 2 with a transformation matrix
This type describes the rotation from a frame 1 into a frame 2. An instance R of type Orientation has the following interpretation:
T = [ex, ey, ez]; e.g., T = [1,0,0; 0,1,0; 0,0,1]
where ex,ey,ez are unit vectors in the direction of the x-axis, y-axis, and z-axis of frame 1, resolved in frame 2, respectively. Therefore, if v1 is vector v resolved in frame 1 and v2 is vector v resolved in frame 2, the following relationship holds:
v2 = T * v1
The inverse orientation T_inv = TT describes the rotation from frame 2 into frame 1.
Since the orientation is described by 9 variables, there are 6 constraints between these variables. These constraints are defined in function TransformationMatrices.orientationConstraint.
Note, that in the MultiBody library the rotation object is never directly accessed but only with the access functions provided in package TransformationMatrices. As a consequence, other implementations of Rotation can be defined by adapting this package correspondingly.
Extends from Internal.TransformationMatrix.
New type defining the first time derivative of Orientation
Name | Value |
---|---|
Custom Parameters | |
unit | "1/s" |
Return residues of orientation constraints (shall be zero)
residue = TransformationMatrices.orientationConstraint(T);
This function returns the Real residue vector with 6 elements that describes the constraints between the 9 elements of the transformation matrix T.
Frames.orientationConstraint, Quaternions.orientationConstraint.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
residue[6] | Residues of constraints between elements of orientation object (shall be zero) |
Return angular velocity resolved in frame 1 from orientation object and its derivative
w = TransformationMatrices.angularVelocity1(T, der_T);
This function returns the angular velocity w of frame 2 with respect to frame 1, resolved in frame 1, from the transformation matrix T that describes the orientation to rotate frame 1 into frame 2 and from its first time derivative der_T:
w = vec( der(transpose(T)) * T ).
Frames.angularVelocity1, Quaternions.angularVelocity1.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
der_T | Derivative of T [1/s] |
Name | Description |
---|---|
w[3] | Angular velocity of frame 2 with respect to frame 1 resolved in frame 1 [rad/s] |
Return angular velocity resolved in frame 2 from orientation object and its derivative
w = TransformationMatrices.angularVelocity2(T, der_T);
This function returns the angular velocity w of frame 2 with respect to frame 1, resolved in frame 2, from the transformation matrix T that describes the orientation to rotate frame 1 into frame 2 and from its first time derivative der_T:
w = vec( T * der(transpose(T)) ).
Frames.angularVelocity2, Quaternions.angularVelocity2.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
der_T | Derivative of T [1/s] |
Name | Description |
---|---|
w[3] | Angular velocity of frame 2 with respect to frame 1 resolved in frame 2 [rad/s] |
Transform vector from frame 2 to frame 1
v1 = TransformationMatrices.resolve1(T, v2);
This function returns vector v resolved in frame 1 (=v1) from vector v resolved in frame 2 (=v2) using the transformation matrix T that describes the orientation to rotate frame 1 into frame 2.
resolve2, Frames.resolve1, Quaternions.resolve1.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
v2[3] | Vector in frame 2 |
Name | Description |
---|---|
v1[3] | Vector in frame 1 |
Transform vector from frame 1 to frame 2
v2 = TransformationMatrices.resolve2(T, v1);
This function returns vector v resolved in frame 2 (=v2) from vector v resolved in frame 1 (=v1) using the transformation matrix T that describes the orientation to rotate frame 1 into frame 2.
resolve1, Frames.resolve2, Quaternions.resolve2.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
v1[3] | Vector in frame 1 |
Name | Description |
---|---|
v2[3] | Vector in frame 2 |
Transform several vectors from frame 2 to frame 1
v1 = TransformationMatrices.multipleResolve1(T, v2);
This function returns vectors v resolved in frame 1 (=v1) from vectors v resolved in frame 2 (=v2) using the transformation matrix T that describes the orientation to rotate frame 1 into frame 2.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
v2[3, :] | Vectors in frame 2 |
Name | Description |
---|---|
v1[3, size(v2, 2)] | Vectors in frame 1 |
Transform several vectors from frame 1 to frame 2
v2 = TransformationMatrices.multipleResolve2(T, v1);
This function returns vectors v resolved in frame 2 (=v2) from vectors v resolved in frame 1 (=v1) using the transformation matrix T that describes the orientation to rotate frame 1 into frame 2.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
v1[3, :] | Vectors in frame 1 |
Name | Description |
---|---|
v2[3, size(v1, 2)] | Vectors in frame 2 |
Transform second order tensor from frame 2 to frame 1
D1 = TransformationMatrices.resolveDyade1(T, D2);
This function returns the second order tensor D resolved in frame 1 (= D1) from its representation in frame 2 (= D2) using the transformation matrix T that describes the orientation to rotate frame 1 into frame 2.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
D2[3, 3] | Second order tensor resolved in frame 2 |
Name | Description |
---|---|
D1[3, 3] | Second order tensor resolved in frame 1 |
Transform second order tensor from frame 1 to frame 2
D2 = TransformationMatrices.resolveDyade2(T, D1);
This function returns the second order tensor D resolved in frame 2 (= D2) from its representation in frame 1 (= D1) using the transformation matrix T that describes the orientation to rotate frame 1 into frame 2.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
D1[3, 3] | Second order tensor resolved in frame 1 |
Name | Description |
---|---|
D2[3, 3] | Second order tensor resolved in frame 2 |
Return orientation object that does not rotate a frame
T = TransformationMatrices.nullRotation();
This function returns a transformation matrix T describing the orientation object to rotate frame 1 into frame 2, if frame 1 and frame 2 are identical. (= transformation matrix is identity matrix and angular velocity is zero).
Frames.nullRotation, Quaternions.nullRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object such that frame 1 and frame 2 are identical |
Return inverse orientation object
T_inv = TransformationMatrices.inverseRotation(T);
This function returns transformation matrix T_inv that describes the orientation to rotate from frame 2 to frame 1 from the transformation matrix T that describes the orientation to rotate from frame 1 into frame 2.
Frames.inverseRotation, Quaternions.inverseRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
T_inv | Orientation object to rotate frame 2 into frame 1 |
Return relative orientation object
T_rel = TransformationMatrices.relativeRotation(T1, T2);
This function returns transformation matrix T_rel that describes the orientation to rotate frame 1 to frame 2 from the transformation matrix T1 that describes the orientation to rotate from frame 0 to frame 1 and from the transformation matrix T2 that describes the orientation to rotate from frame 0 to frame 2.
Frames.relativeRotation, Quaternions.relativeRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T1 | Orientation object to rotate frame 0 into frame 1 |
T2 | Orientation object to rotate frame 0 into frame 2 |
Name | Description |
---|---|
T_rel | Orientation object to rotate frame 1 into frame 2 |
Return absolute orientation object from another absolute and a relative orientation object
T2 = TransformationMatrices.absoluteRotation(T1, T_rel);
This function returns transformation matrix T2 that describes the orientation frame 0 to frame 2 from the transformation matrix T1 that describes the orientation to rotate from frame 0 to frame 1 and from the relative transformation matrix T2_rel that describes the orientation to rotate from frame 1 to frame 2.
Frames.absoluteRotation, Quaternions.absoluteRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T1 | Orientation object to rotate frame 0 into frame 1 |
T_rel | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
T2 | Orientation object to rotate frame 0 into frame 2 |
Return orientation object of a planar rotation
T = TransformationMatrices.planarRotation(e, angle);
This function returns transformation matrix T that describes the orientation to rotate in the plane along unit axis e from frame 1 into frame 2 with angle angle. Note, "e" must be a unit vector. However, this is not checked in this function and the function will return a wrong result, if length(e) is not one.
planarRotationAngle, Frames.planarRotation, Quaternions.planarRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
e[3] | Normalized axis of rotation (must have length=1) [1] |
angle | Rotation angle to rotate frame 1 into frame 2 along axis e [rad] |
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Return angle of a planar rotation, given the rotation axis and the representations of a vector in frame 1 and frame 2
angle = TransformationMatrices.planarRotationAngle(e, v1, v2);
A call to this function of the form
Real[3] e, v1, v2; Modelica.SIunits.Angle angle; equation angle = planarRotationAngle(e, v1, v2);
computes the rotation angle "angle" of a planar rotation along unit vector e, rotating frame 1 into frame 2, given the coordinate representations of a vector "v" in frame 1 (v1) and in frame 2 (v2). Therefore, the result of this function fulfills the following equation:
v2 = resolve2(planarRotation(e,angle), v1)
The rotation angle is returned in the range
-p <= angle <= p
This function makes the following assumptions on the input arguments
The function does not check the above assumptions. If these assumptions are violated, a wrong result will be returned and/or a division by zero will occur.
planarRotation, Frames.planarRotationAngle.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
e[3] | Normalized axis of rotation to rotate frame 1 around e into frame 2 (must have length=1) [1] |
v1[3] | A vector v resolved in frame 1 (shall not be parallel to e) |
v2[3] | Vector v resolved in frame 2, i.e., v2 = resolve2(planarRotation(e,angle),v1) |
Name | Description |
---|---|
angle | Rotation angle to rotate frame 1 into frame 2 along axis e in the range: -pi <= angle <= pi [rad] |
Return rotation object to rotate around one frame axis
T = TransformationMatrices.axisRotation(axis, angle);
This function returns transformation matrix T that describes the orientation to rotate along unit axis axis from frame 1 into frame 2 with angle angle. For example, TransformationMatrices.axisRotation(2, phi) returns the same orientation object as with the call TransformationMatrices.planarRotation({0,1,0}, phi)
planarRotation, Frames.axisRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
axis | Rotate around 'axis' of frame 1 |
angle | Rotation angle to rotate frame 1 into frame 2 along 'axis' of frame 1 [rad] |
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Return rotation object to rotate in sequence around 3 axes
T = TransformationMatrices.axesRotations(sequence, angles);
This function returns transformation matrix T that describes the orientation defined by three elementary rotations in a given sequence, each rotated by angles.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
sequence[3] | Sequence of rotations from frame 1 to frame 2 along axis sequence[i] |
angles[3] | Rotation angles around the axes defined in 'sequence' [rad] |
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Return the 3 angles to rotate in sequence around 3 axes to construct the given orientation object
angles = TransformationMatrices.axesRotationsAngles(T, sequence, guessAngle1);
A call to this function of the form
TransformationMatrices.Orientation T; parameter Integer sequence[3] = {1,2,3}; Modelica.SIunits.Angle angles[3]; equation angle = axesRotationAngles(T, sequence);
computes the rotation angles "angles[1:3]" to rotate frame 1 into frame 2 along axes sequence[1:3], given the transformation matrix T from frame 1 to frame 2. Therefore, the result of this function fulfills the following equation:
T = axesRotation(sequence, angles)
The rotation angles are returned in the range
-p <= angles[i] <= p
There are two solutions for "angles[1]" in this range. Via the third argument guessAngle1 (default = 0) the returned solution is selected such that |angles[1] - guessAngle1| is minimal. The orientation object T may be in a singular configuration, i.e., there is an infinite number of angle values leading to the same T. The returned solution is selected by setting angles[1] = guessAngle1. Then angles[2] and angles[3] can be uniquely determined in the above range.
Note, that input argument sequence has the restriction that only values 1,2,3 can be used and that sequence[1] ≠ sequence[2] and sequence[2] ≠ sequence[3]. Often used values are:
sequence = {1,2,3} // Cardan angle sequence = {3,1,3} // Euler angle sequence = {3,2,1} // Tait-Bryan angle sequence
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
sequence[3] | Sequence of rotations from frame 1 to frame 2 along axis sequence[i] |
guessAngle1 | Select angles[1] such that |angles[1] - guessAngle1| is a minimum [rad] |
Name | Description |
---|---|
angles[3] | Rotation angles around the axes defined in 'sequence' such that T=TransformationMatrices.axesRotation(sequence,angles); -pi < angles[i] <= pi [rad] |
Return rotation angles valid for a small rotation and optionally residues that should be zero
phi = TransformationMatrices.smallRotation(T, withResidues);
This function returns rotation angles valid for a small rotation of x-y-z sequence (i.e. {1,2,3}).
Optionally, residues are returned as well if withResidues=true
.
Frames.smallRotation, Quaternions.smallRotation.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
withResidues | = false/true, if 'angles'/'angles and residues' are returned in phi |
Name | Description |
---|---|
phi[if withResidues then 6 else 3] | The rotation angles around x-, y-, and z-axis of frame 1 to rotate frame 1 into frame 2 for a small rotation + optionally 3 residues that should be zero [rad] |
Return orientation object from n_x and n_y vectors
T = TransformationMatrices.from_nxy(n_x, n_y);
It is assumed that the two input vectors n_x and n_y are resolved in frame 1 and are directed along the x and y axis of frame 2 (i.e., n_x and n_y are orthogonal to each other). The function returns the orientation object T to rotate from frame 1 to frame 2.
The function is robust in the sense that it returns always
an orientation object T, even if n_y is not orthogonal to n_x.
This is performed in the following way:
If n_x and n_y are not orthogonal to each other, first a unit
vector e_y is determined that is orthogonal to n_x and is lying
in the plane spanned by n_x and n_y. If n_x and n_y are parallel
or nearly parallel to each other, a vector e_y is selected
arbitrarily such that e_x and e_y are orthogonal to each other.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
n_x[3] | Vector in direction of x-axis of frame 2, resolved in frame 1 [1] |
n_y[3] | Vector in direction of y-axis of frame 2, resolved in frame 1 [1] |
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Return orientation object from n_x and n_z vectors
T = TransformationMatrices.from_nxz(n_x, n_z);
It is assumed that the two input vectors n_x and n_z are resolved in frame 1 and are directed along the x and z axis of frame 2 (i.e., n_x and n_z are orthogonal to each other). The function returns the orientation object T to rotate from frame 1 to frame 2.
The function is robust in the sense that it returns always
an orientation object T, even if n_z is not orthogonal to n_x.
This is performed in the following way:
If n_x and n_z are not orthogonal to each other, first a unit
vector e_z is determined that is orthogonal to n_x and is lying
in the plane spanned by n_x and n_z. If n_x and n_z are parallel
or nearly parallel to each other, a vector e_z is selected
arbitrarily such that n_x and e_z are orthogonal to each other.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
n_x[3] | Vector in direction of x-axis of frame 2, resolved in frame 1 [1] |
n_z[3] | Vector in direction of z-axis of frame 2, resolved in frame 1 [1] |
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Return orientation object R from transformation matrix T
R = TransformationMatrices.from_T(T);
This function returns a transformation matrix R which is equal to a real input matrix T.
from_T_inv, to_T, Frames.from_T.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T[3, 3] | Transformation matrix to transform vector from frame 1 to frame 2 (v2=T*v1) |
Name | Description |
---|---|
R | Orientation object to rotate frame 1 into frame 2 |
Return orientation object R from inverse transformation matrix T_inv
R = TransformationMatrices.from_T_inv(T_inv);
This function returns a transformation matrix R which is inverse to real input matrix T_inv.
to_T_inv, from_T, Frames.from_T_inv.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T_inv[3, 3] | Inverse transformation matrix to transform vector from frame 2 to frame 1 (v1=T_inv*v2) |
Name | Description |
---|---|
R | Orientation object to rotate frame 1 into frame 2 |
Return orientation object T from quaternion orientation object Q
T = TransformationMatrices.from_Q(Q);
This function returns a transformation matrix T computed from a quaternion object Q
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
Q | Quaternions orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Return transformation matrix T from orientation object R
T = TransformationMatrices.to_T(R);
This function returns a real matrix T which is equal to a transformation matrix R.
from_T, to_T_inv, Frames.to_T, Quaternions.to_T.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
R | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
T[3, 3] | Transformation matrix to transform vector from frame 1 to frame 2 (v2=T*v1) |
Return inverse transformation matrix T_inv from orientation object R
T_inv = TransformationMatrices.to_T_inv(R);
This function returns a real matrix T_inv which is inverse to a transformation matrix R.
from_T_inv, to_T, Frames.to_T_inv, Quaternions.to_T_inv.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
R | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
T_inv[3, 3] | Inverse transformation matrix to transform vector from frame 2 into frame 1 (v1=T_inv*v2) |
Return quaternion orientation object Q from orientation object T
Q = TransformationMatrices.to_Q(T, Q_guess);
This function returns a quaternion object Q computed from a transformation matrix T and depending on the initial guess Q_guess.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Q_guess | Guess value for output Q (there are 2 solutions; the one closer to Q_guess is used |
Name | Description |
---|---|
Q | Quaternions orientation object to rotate frame 1 into frame 2 |
Map rotation object into vector
vec = TransformationMatrices.to_vector(T);
This function returns a vector vec which contains elements of a transformation matrix T.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
vec[9] | Elements of T in one vector |
Map rotation object into e_x and e_y vectors of frame 2, resolved in frame 1
exy = TransformationMatrices.to_exy(T);
This function returns unit vectors e_x and e_y which define axes of frame 2 resolved in frame 1, provided T is a transformation matrix to rotate frame 1 into 2.
from_nxy, from_nxz, Frames.to_exy.
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
T | Orientation object to rotate frame 1 into frame 2 |
Name | Description |
---|---|
exy[3, 2] | = [e_x, e_y] where e_x and e_y are axes unit vectors of frame 2, resolved in frame 1 |