Detailed Description

template<typename T>
class drake::trajectories::BsplineTrajectory< T >

Represents a B-spline curve using a given basis with ordered control_points such that each control point is a matrix in ℝʳᵒʷˢ ˣ ᶜᵒˡˢ.

See also: math::BsplineBasis

Template Parameters

T	The scalar type, which must be one of the default scalars.

#include <drake/common/trajectories/bspline_trajectory.h>

Public Member Functions
	BsplineTrajectory ()

	BsplineTrajectory (math::BsplineBasis< T > basis, std::vector< MatrixX< T >> control_points)
	Constructs a B-spline trajectory with the given `basis` and `control_points`. More...

	BsplineTrajectory (math::BsplineBasis< double > basis, std::vector< MatrixX< T >> control_points)
	Constructs a T-valued B-spline trajectory from a double-valued `basis` and T-valued `control_points`. More...

	~BsplineTrajectory () final

MatrixX< T >	value (const T &t) const final
	Evaluates the BsplineTrajectory at the given time t. More...

Eigen::SparseMatrix< T >	AsLinearInControlPoints (int derivative_order=1) const
	Supports writing optimizations using the control points as decision variables. More...

VectorX< T >	EvaluateLinearInControlPoints (const T &t, int derivative_order=0) const
	Returns the vector, M, such that. More...

int	num_control_points () const
	Returns the number of control points in this curve. More...

const std::vector< MatrixX< T > > &	control_points () const
	Returns the control points of this curve. More...

MatrixX< T >	InitialValue () const
	Returns this->value(this->start_time()) More...

MatrixX< T >	FinalValue () const
	Returns this->value(this->end_time()) More...

const math::BsplineBasis< T > &	basis () const
	Returns the basis of this curve. More...

void	InsertKnots (const std::vector< T > &additional_knots)
	Adds new knots at the specified `additional_knots` without changing the behavior of the trajectory. More...

BsplineTrajectory< T >	CopyWithSelector (const std::function< MatrixX< T >(const MatrixX< T > &)> &select) const
	Returns a new BsplineTrajectory that uses the same basis as `this`, and whose control points are the result of calling `select(point)` on each `point` in `this->control_points()`. More...

BsplineTrajectory< T >	CopyBlock (int start_row, int start_col, int block_rows, int block_cols) const
	Returns a new BsplineTrajectory that uses the same basis as `this`, and whose control points are the result of calling `point.block(start_row, start_col, block_rows, block_cols)` on each `point` in `this->control_points()`. More...

BsplineTrajectory< T >	CopyHead (int n) const
	Returns a new BsplineTrajectory that uses the same basis as `this`, and whose control points are the result of calling `point.head(n)` on each `point` in `this->control_points()`. More...

boolean< T >	operator== (const BsplineTrajectory< T > &other) const

template<typename Archive >
void	Serialize (Archive *a)
	Passes this object to an Archive. More...

Implements CopyConstructible, CopyAssignable, MoveConstructible, MoveAssignable
	BsplineTrajectory (const BsplineTrajectory &)=default

BsplineTrajectory &	operator= (const BsplineTrajectory &)=default

	BsplineTrajectory (BsplineTrajectory &&)=default

BsplineTrajectory &	operator= (BsplineTrajectory &&)=default

Public Member Functions inherited from Trajectory< T >
virtual	~Trajectory ()

virtual std::unique_ptr< Trajectory< T > >	Clone () const

MatrixX< T >	vector_values (const std::vector< T > &t) const
	If cols()==1, then evaluates the trajectory at each time `t`, and returns the results as a Matrix with the ith column corresponding to the ith time. More...

MatrixX< T >	vector_values (const Eigen::Ref< const VectorX< T >> &t) const
	If cols()==1, then evaluates the trajectory at each time `t`, and returns the results as a Matrix with the ith column corresponding to the ith time. More...

bool	has_derivative () const
	Returns true iff the Trajectory provides and implementation for EvalDerivative() and MakeDerivative(). More...

MatrixX< T >	EvalDerivative (const T &t, int derivative_order=1) const
	Evaluates the derivative of `this` at the given time `t`. More...

std::unique_ptr< Trajectory< T > >	MakeDerivative (int derivative_order=1) const
	Takes the derivative of this Trajectory. More...

virtual Eigen::Index	rows () const

virtual Eigen::Index	cols () const

virtual T	start_time () const

virtual T	end_time () const

Additional Inherited Members
Protected Member Functions inherited from Trajectory< T >
	Trajectory ()=default

	Trajectory (const Trajectory &)=default

Trajectory &	operator= (const Trajectory &)=default

	Trajectory (Trajectory &&)=default

Trajectory &	operator= (Trajectory &&)=default

Constructor & Destructor Documentation

◆ BsplineTrajectory() [1/5]

BsplineTrajectory ( const BsplineTrajectory< T > & )

default

◆ BsplineTrajectory() [2/5]

BsplineTrajectory ( BsplineTrajectory< T > && )

default

◆ BsplineTrajectory() [3/5]

BsplineTrajectory ( )

◆ BsplineTrajectory() [4/5]

BsplineTrajectory	(	math::BsplineBasis< T >	basis,
		std::vector< MatrixX< T >>	control_points
	)

Constructs a B-spline trajectory with the given basis and control_points.

Precondition: control_points.size() == basis.num_basis_functions()

◆ BsplineTrajectory() [5/5]

BsplineTrajectory	(	math::BsplineBasis< double >	basis,
		std::vector< MatrixX< T >>	control_points
	)

Constructs a T-valued B-spline trajectory from a double-valued basis and T-valued control_points.

Precondition: control_points.size() == basis.num_basis_functions()

◆ ~BsplineTrajectory()

~BsplineTrajectory ( )

final

Member Function Documentation

◆ AsLinearInControlPoints()

Eigen::SparseMatrix<T> AsLinearInControlPoints ( int derivative_order = 1 ) const

Supports writing optimizations using the control points as decision variables.

This method returns the matrix, M, defining the control points of the order derivative in the form:

derivative.control_points() = this.control_points() * M

See BezierCurve::AsLinearInControlPoints() for more details.

Precondition: derivative_order >= 0.

◆ basis()

const math::BsplineBasis<T>& basis ( ) const

Returns the basis of this curve.

◆ control_points()

const std::vector<MatrixX<T> >& control_points ( ) const

Returns the control points of this curve.

◆ CopyBlock()

BsplineTrajectory<T> CopyBlock	(	int	start_row,
		int	start_col,
		int	block_rows,
		int	block_cols
	)		const

Returns a new BsplineTrajectory that uses the same basis as this, and whose control points are the result of calling point.block(start_row, start_col, block_rows, block_cols) on each point in this->control_points().

◆ CopyHead()

BsplineTrajectory<T> CopyHead ( int n ) const

Returns a new BsplineTrajectory that uses the same basis as this, and whose control points are the result of calling point.head(n) on each point in this->control_points().

Precondition: this->cols() == 1; control_points()[0].head(n) must be a valid operation.

◆ CopyWithSelector()

BsplineTrajectory<T> CopyWithSelector ( const std::function< MatrixX< T >(const MatrixX< T > &)> & select ) const

Returns a new BsplineTrajectory that uses the same basis as this, and whose control points are the result of calling select(point) on each point in this->control_points().

◆ EvaluateLinearInControlPoints()

VectorX<T> EvaluateLinearInControlPoints	(	const T &	t,
		int	derivative_order = `0`
	)		const

Returns the vector, M, such that.

EvalDerivative(t, derivative_order) = control_points() * M

where cols()==1 (so control_points() is a matrix). This is useful for writing linear constraints on the control points. Note that if the derivative order is greater than or equal to the order of the basis, then the result is a zero vector.

Precondition: t ≥ start_time(); t ≤ end_time()

◆ FinalValue()

MatrixX<T> FinalValue ( ) const

Returns this->value(this->end_time())

◆ InitialValue()

MatrixX<T> InitialValue ( ) const

Returns this->value(this->start_time())

◆ InsertKnots()

void InsertKnots ( const std::vector< T > & additional_knots )

Adds new knots at the specified additional_knots without changing the behavior of the trajectory.

The basis and control points of the trajectory are adjusted such that it produces the same value for any valid time before and after this method is called. The resulting trajectory is guaranteed to have the same level of continuity as the original, even if knot values are duplicated. Note that additional_knots need not be sorted.

Precondition: start_time() <= t <= end_time() for all t in additional_knots

◆ num_control_points()

int num_control_points ( ) const

Returns the number of control points in this curve.

◆ operator=() [1/2]

BsplineTrajectory& operator= ( BsplineTrajectory< T > && )

default

◆ operator=() [2/2]

BsplineTrajectory& operator= ( const BsplineTrajectory< T > & )

default

◆ operator==()

boolean<T> operator== ( const BsplineTrajectory< T > & other ) const

◆ Serialize()

void Serialize ( Archive * a )

Passes this object to an Archive.

Refer to YAML Serialization for background. This method is only available when T = double.

◆ value()

MatrixX<T> value ( const T & t ) const

finalvirtual

Evaluates the BsplineTrajectory at the given time t.

Parameters

t	The time at which to evaluate the BsplineTrajectory.

Returns: The matrix of evaluated values.

Precondition: If T == symbolic::Expression, t.is_constant() must be true.

Warning: If t does not lie in the range [start_time(), end_time()], the trajectory will silently be evaluated at the closest valid value of time to t. For example, value(-1) will return value(0) for a trajectory defined over [0, 1].

Reimplemented from Trajectory< T >.

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

drake/common/trajectories/bspline_trajectory.h

Detailed Description

template<typename T> class drake::trajectories::BsplineTrajectory< T >

Public Member Functions

Additional Inherited Members

Constructor & Destructor Documentation

◆ BsplineTrajectory() [1/5]

◆ BsplineTrajectory() [2/5]

◆ BsplineTrajectory() [3/5]

◆ BsplineTrajectory() [4/5]

◆ BsplineTrajectory() [5/5]

◆ ~BsplineTrajectory()

Member Function Documentation

◆ AsLinearInControlPoints()

◆ basis()

◆ control_points()

◆ CopyBlock()

◆ CopyHead()

◆ CopyWithSelector()

◆ EvaluateLinearInControlPoints()

◆ FinalValue()

◆ InitialValue()

◆ InsertKnots()

◆ num_control_points()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ operator==()

◆ Serialize()

◆ value()

template<typename T>
class drake::trajectories::BsplineTrajectory< T >