AngleBetweenVectorsCost Class Reference

Detailed Description

Implements a cost of the form c*(1-cosθ), where θ is the angle between two vectors a and b.

c is a constant scalar.

#include <drake/multibody/inverse_kinematics/angle_between_vectors_cost.h>

Public Member Functions
	AngleBetweenVectorsCost (const MultibodyPlant< double > *plant, const Frame< double > &frameA, const Eigen::Ref< const Eigen::Vector3d > &a_A, const Frame< double > &frameB, const Eigen::Ref< const Eigen::Vector3d > &b_B, double c, systems::Context< double > *plant_context)
	Constructs an AngleBetweenVectorsCost. More...
	AngleBetweenVectorsCost (const MultibodyPlant< AutoDiffXd > *plant, const Frame< AutoDiffXd > &frameA, const Eigen::Ref< const Eigen::Vector3d > &a_A, const Frame< AutoDiffXd > &frameB, const Eigen::Ref< const Eigen::Vector3d > &b_B, double c, systems::Context< AutoDiffXd > *plant_context)
	Overloaded constructor. More...
	~AngleBetweenVectorsCost () override
Does not allow copy, move, or assignment
	AngleBetweenVectorsCost (const AngleBetweenVectorsCost &)=delete
AngleBetweenVectorsCost &	operator= (const AngleBetweenVectorsCost &)=delete
	AngleBetweenVectorsCost (AngleBetweenVectorsCost &&)=delete
AngleBetweenVectorsCost &	operator= (AngleBetweenVectorsCost &&)=delete
Public Member Functions inherited from Cost
	Cost (const Cost &)=delete
Cost &	operator= (const Cost &)=delete
	Cost (Cost &&)=delete
Cost &	operator= (Cost &&)=delete
Public Member Functions inherited from EvaluatorBase
virtual	~EvaluatorBase ()
void	Eval (const Eigen::Ref< const Eigen::VectorXd > &x, Eigen::VectorXd *y) const
	Evaluates the expression. More...
void	Eval (const Eigen::Ref< const AutoDiffVecXd > &x, AutoDiffVecXd *y) const
	Evaluates the expression. More...
void	Eval (const Eigen::Ref< const VectorX< symbolic::Variable >> &x, VectorX< symbolic::Expression > *y) const
	Evaluates the expression. More...
void	set_description (const std::string &description)
	Set a human-friendly description for the evaluator. More...
const std::string &	get_description () const
	Getter for a human-friendly description for the evaluator. More...
std::ostream &	Display (std::ostream &os, const VectorX< symbolic::Variable > &vars) const
	Formats this evaluator into the given stream using vars for the bound decision variable names. More...
std::ostream &	Display (std::ostream &os) const
	Formats this evaluator into the given stream, without displaying the decision variables it is bound to. More...
std::string	ToLatex (const VectorX< symbolic::Variable > &vars, int precision=3) const
	Returns a LaTeX string describing this evaluator. More...
int	num_vars () const
	Getter for the number of variables, namely the number of rows in x, as used in Eval(x, y). More...
int	num_outputs () const
	Getter for the number of outputs, namely the number of rows in y, as used in Eval(x, y). More...
void	SetGradientSparsityPattern (const std::vector< std::pair< int, int >> &gradient_sparsity_pattern)
	Set the sparsity pattern of the gradient matrix ∂y/∂x (the gradient of y value in Eval, w.r.t x in Eval) . More...
const std::optional< std::vector< std::pair< int, int > > > &	gradient_sparsity_pattern () const
	Returns the vector of (row_index, col_index) that contains all the entries in the gradient of Eval function (∂y/∂x) whose value could be non-zero, namely if ∂yᵢ/∂xⱼ could be non-zero, then the pair (i, j) is in gradient_sparsity_pattern. More...
bool	is_thread_safe () const
	Returns whether it is safe to call Eval in parallel. More...
	EvaluatorBase (const EvaluatorBase &)=delete
EvaluatorBase &	operator= (const EvaluatorBase &)=delete
	EvaluatorBase (EvaluatorBase &&)=delete
EvaluatorBase &	operator= (EvaluatorBase &&)=delete

Additional Inherited Members
Protected Member Functions inherited from Cost
	Cost (int num_vars, const std::string &description="")
	Constructs a cost evaluator. More...
Protected Member Functions inherited from EvaluatorBase
	EvaluatorBase (int num_outputs, int num_vars, const std::string &description="")
	Constructs a evaluator. More...
virtual std::ostream &	DoDisplay (std::ostream &os, const VectorX< symbolic::Variable > &vars) const
	NVI implementation of Display. More...
virtual std::string	DoToLatex (const VectorX< symbolic::Variable > &vars, int precision) const
void	set_num_outputs (int num_outputs)
void	set_is_thread_safe (bool is_thread_safe)

Constructor & Destructor Documentation

AngleBetweenVectorsCost() [1/4]

AngleBetweenVectorsCost ( const AngleBetweenVectorsCost &  )

delete

AngleBetweenVectorsCost() [2/4]

AngleBetweenVectorsCost ( AngleBetweenVectorsCost &&  )

delete

AngleBetweenVectorsCost() [3/4]

AngleBetweenVectorsCost	(	const MultibodyPlant< double > *	plant,
		const Frame< double > &	frameA,
		const Eigen::Ref< const Eigen::Vector3d > &	a_A,
		const Frame< double > &	frameB,
		const Eigen::Ref< const Eigen::Vector3d > &	b_B,
		double	c,
		systems::Context< double > *	plant_context
	)

Constructs an AngleBetweenVectorsCost.

Parameters

plant	The MultibodyPlant on which the cost is imposed. plant should be alive during the lifetime of this cost.
frameA	The Frame object for frame A.
a_A	The vector a fixed to frame A, expressed in frame A.
frameB	The Frame object for frame B.
b_B	The vector b fixed to frame B, expressed in frameB.
c	The cost is c*(1-cosθ).
plant_context	The Context that has been allocated for this plant. We will update the context when evaluating the constraint. plant_context should be alive during the lifetime of this cost.

Precondition

frameA and frameB must belong to plant.

Exceptions

std::exception	if plant is nullptr.
std::exception	if a_A is close to zero.
std::exception	if b_B is close to zero.
std::exception	if plant_context is nullptr.

AngleBetweenVectorsCost() [4/4]

AngleBetweenVectorsCost	(	const MultibodyPlant< AutoDiffXd > *	plant,
		const Frame< AutoDiffXd > &	frameA,
		const Eigen::Ref< const Eigen::Vector3d > &	a_A,
		const Frame< AutoDiffXd > &	frameB,
		const Eigen::Ref< const Eigen::Vector3d > &	b_B,
		double	c,
		systems::Context< AutoDiffXd > *	plant_context
	)

Overloaded constructor.

Use MultibodyPlant<AutoDiffXd> instead of MultibodyPlant<double>.

~AngleBetweenVectorsCost()

~AngleBetweenVectorsCost ( )

override

Member Function Documentation

operator=() [1/2]

AngleBetweenVectorsCost& operator= ( const AngleBetweenVectorsCost &  )

delete

operator=() [2/2]

AngleBetweenVectorsCost& operator= ( AngleBetweenVectorsCost &&  )

delete

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

• drake/multibody/inverse_kinematics/angle_between_vectors_cost.h