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Class inertialsim::geometry::Rotation

ClassList > inertialsim > geometry > Rotation

3-dimensional rotations of rigid bodies. More...

  • #include <rotation.h>

Inherits the following classes: inertialsim::geometry::RotationBase

Public Types inherited from inertialsim::geometry::RotationBase

See inertialsim::geometry::RotationBase

Type Name
typedef MatrixLieGroup< Derived, 3, 3 > Base

Public Types inherited from inertialsim::geometry::MatrixLieGroup

See inertialsim::geometry::MatrixLieGroup

Type Name
typedef Eigen::Matrix< Scalar, AlgebraDimension, Eigen::Dynamic > AlgebraArray
Matrix of algebra elements (rows = axes, cols = samples).
typedef Eigen::Matrix< Scalar, AlgebraDimension, 1 > AlgebraElement
Algebra element type (vector).
typedef std::vector< GroupElement > GroupArray
Array of group elements.
typedef Eigen::Matrix< Scalar, GroupDimension, GroupDimension > GroupElement
Group element type (square matrix).
typedef Eigen::Matrix< Scalar, AlgebraDimension, AlgebraDimension > JacobianMatrix
Jacobian matrix (algebra to algebra).
typedef std::vector< JacobianMatrix > JacobianMatrixArray
Array of Jacobian matrices.

Public Functions inherited from inertialsim::geometry::RotationBase

See inertialsim::geometry::RotationBase

Type Name
AxisAngle AsAxisAngle () const
Return axis and angle representation.
EulerAngles AsEuler (const std::string & sequence) const
Return the Euler angle representation.
const RotationMatrixArray & AsMatrix () const
Return the rotation matrix representation.
Quaternion AsQuaternion () const
Return the quaternion representation.
RotationVector AsRotationVector () const
Return the rotation vector representation.
RotationVector Error (const RotationBase< OtherDerived > & reference) const
Calculate error compared to a reference rotation.
int num_rotations () const
Number of rotations stored.

Public Functions inherited from inertialsim::geometry::MatrixLieGroup

See inertialsim::geometry::MatrixLieGroup

Type Name
Vector3D Apply (const Vector3D & vectors) const
Apply the group action to an array of vectors.
Derived Interpolate (const Timestamps & interp_time, Interpolator method=Interpolator::LINEAR) const
Interpolate at given times.
Derived Inverse () const
Invert an instance.
Derived Slice (int start, int end) const
Get a slice of elements.
AlgebraArray TimeDerivative (int order=1, int accuracy=4, const std::string & side="right") const
Compute time derivative using finite differences.
int num_elements () const
Number of elements stored in the instance.
Derived operator* (const Derived & rhs) const
Composition operator on the matrix group. Supports broadcasting: if either lhs or rhs has size 1, it will be broadcast against all elements of the other operand. Derived classes may implement more efficient methods.
Derived operator[] (int index) const
Get a single element by index.
const std::optional< Timestamps > & time () const
Time array (or nullopt if not set).
virtual ~MatrixLieGroup () = default

Public Static Functions inherited from inertialsim::geometry::RotationBase

See inertialsim::geometry::RotationBase

Type Name
RotationMatrixArray DoubleIntegralFactor (const RotationVector & rotation_vectors)
Double integral factor.
Derived FromAxisAngle (const Vector3D & axis, const Scalar1D & angle, const std::optional< Timestamps > & time=std::nullopt)
Construct a Rotation from an axis and angle.
Derived FromEuler (const EulerAngles & euler, const std::string & sequence, const std::optional< Timestamps > & time=std::nullopt)
Construct a Rotation from a sequence of Euler angles.
Derived FromMatrix (const RotationMatrixArray & matrices, const std::optional< Timestamps > & time=std::nullopt, bool orthonormalize=false)
Construct a Rotation from rotation matrices.
Derived FromQuaternion (const Quaternion & quaternions, const std::optional< Timestamps > & time=std::nullopt, bool scalar_last=false)
Construct a Rotation from quaternions.
Derived FromRotationVector (const RotationVector & rotation_vectors, const std::optional< Timestamps > & time=std::nullopt)
Construct a Rotation from rotation vectors.
RotationMatrixArray IntegralFactor (const RotationVector & rotation_vectors)
First integral factor.

Public Static Functions inherited from inertialsim::geometry::MatrixLieGroup

See inertialsim::geometry::MatrixLieGroup

Type Name
Derived Compose (const std::vector< Derived > & instances)
Compose a sequence of instances (first to last).
Derived FromIdentity (int num_elements=1)
Create identity elements.
Derived FromRandom (int num_elements=1, std::optional< Eigen::numext::uint64_t > seed=std::nullopt)
Create random elements.

Protected Functions inherited from inertialsim::geometry::RotationBase

See inertialsim::geometry::RotationBase

Type Name
Vector3D ApplyImpl (const Vector3D & vectors) const
Apply rotation to vectors.
AlgebraArray AsAlgebraImpl () const
Return algebra representation.
GroupArray AsGroupImpl () const
Return as group elements (for CRTP interface).
Derived InverseImpl () const
Return the inverse rotation.
RotationBase ()
Default constructor.
RotationBase (const RotationMatrixArray & matrices, const std::optional< Timestamps > & time=std::nullopt)
Construct from rotation matrices.
int num_elements_impl () const
Number of rotations stored.

Protected Functions inherited from inertialsim::geometry::MatrixLieGroup

See inertialsim::geometry::MatrixLieGroup

Type Name
AlgebraArray AsAlgebra () const
Get the algebra elements.
GroupArray AsGroup () const
Get the group elements.
Derived CubicHermiteInterpolate (const Timestamps & time) const
Cubic Hermite spline interpolation.
Derived LinearInterpolate (const Timestamps & time) const
Linear interpolation implementation.
MatrixLieGroup (const std::optional< Timestamps > & time=std::nullopt)
Constructor.
Derived & derived ()
CRTP helper to access derived class.
const Derived & derived () const
int num_times () const

Protected Static Functions inherited from inertialsim::geometry::RotationBase

See inertialsim::geometry::RotationBase

Type Name
GroupElement ExpImpl (const AlgebraElement & rotation_vector)
Exponential map: rotation vector to rotation matrix.
Derived FromAlgebraImpl (const AlgebraArray & rotation_vectors, const std::optional< Timestamps > & time=std::nullopt)
Construct from algebra elements (for CRTP interface).
Derived FromGroupImpl (const GroupArray & elements, const std::optional< Timestamps > & time)
Construct from group elements (for CRTP interface).
Derived FromIdentityImpl (int num_elements)
Construct identity rotations.
Derived FromRandomImpl (int num_rotations, std::optional< uint64_t > seed=std::nullopt)
Construct uniformly distributed random rotations.
JacobianMatrixArray JacobianImpl (const AlgebraArray & rotation_vectors, const std::string & side, bool inverse)
Jacobian of SO(3) exponential map.
AlgebraElement LogImpl (const GroupElement & matrix)
Logarithm map: rotation matrix to rotation vector.

Protected Static Functions inherited from inertialsim::geometry::MatrixLieGroup

See inertialsim::geometry::MatrixLieGroup

Type Name
GroupElement Exp (const AlgebraElement & vector)
Exponential map from algebra to group.
Derived FromAlgebra (const AlgebraArray & elements, const std::optional< Timestamps > & time)
Create instance from algebra elements.
Derived FromGroup (const GroupArray & elements, const std::optional< Timestamps > & time)
Create instance from group elements.
JacobianMatrixArray Jacobian (const AlgebraArray & algebra, const std::string & side="left", bool inverse=false)
Calculate the Jacobian given algebra elements.
AlgebraElement Log (const GroupElement & element)
Logarithm map from group to algebra.

Detailed Description

Rotations can be constructed from any of the following representations: rotation matrix, Euler angles, quaternion, rotation vector, and axis angle. Use the From* methods to construct an instance.

Current state can be returned in any of the representations listed above using the As* methods.

Internally rotations are stored in rotation matrix format.

Warning:

Rotation conventions: There are a large variety of rotation conventions and they are a common source of errors. Because many of these conventions cannot be automatically validated, users must be aware of them and manage interfaces with other software accordingly. InertialSim conventions are documented in each method.

** **

Rotations stored in this class represent an active transformation. In the active convention, rotations act to rotate an object relative to a fixed coordinate system. The active convention is the standard mathematical description of rotations.

The alternative passive convention is supported in the CoordinateRotation subclass. In the passive convention, rotations act to transform the components of physical vectors to different coordinate systems. The passive convention is the standard for describing orientation in inertial navigation and aerospace applications.

Some references use the terminology alibi (active) and alias (passive). Reference [02], Reference [05], and Reference [11] discuss active vs. passive transforms in greater detail.

See also: CoordinateRotation for passive rotations.

See also: RigidTransform for combined rotation and translation.


The documentation for this class was generated from the following file cpp/include/inertialsim/geometry/rotation.h