Define a center of pressure cost function. More...

#include <crocoddyl/multibody/costs/impulse-cop-position.hpp>

Inheritance diagram for CostModelImpulseCoPPositionTpl< _Scalar >:

Collaboration diagram for CostModelImpulseCoPPositionTpl< _Scalar >:

Public Types
typedef ActivationBoundsTpl< Scalar >	ActivationBounds

typedef ActivationModelAbstractTpl< Scalar >	ActivationModelAbstract

typedef ActivationModelQuadraticBarrierTpl< Scalar >	ActivationModelQuadraticBarrier

typedef CostModelResidualTpl< Scalar >	Base

typedef CoPSupportTpl< Scalar >	CoPSupport

typedef FrameCoPSupportTpl< Scalar >	FrameCoPSupport

typedef MathBaseTpl< Scalar >	MathBase

typedef MathBase::Matrix3s	Matrix3s

typedef MathBase::MatrixXs	MatrixXs

typedef StateMultibodyTpl< Scalar >	StateMultibody

typedef MathBase::VectorXs	VectorXs

Public Types inherited from CostModelResidualTpl< _Scalar >
typedef ActivationModelAbstractTpl< Scalar >	ActivationModelAbstract

typedef CostModelAbstractTpl< Scalar >	Base

typedef CostDataAbstractTpl< Scalar >	CostDataAbstract

typedef CostDataResidualTpl< Scalar >	Data

typedef DataCollectorAbstractTpl< Scalar >	DataCollectorAbstract

typedef MathBaseTpl< Scalar >	MathBase

typedef MathBase::MatrixXs	MatrixXs

typedef ResidualModelAbstractTpl< Scalar >	ResidualModelAbstract

typedef MathBase::VectorXs	VectorXs

Public Types inherited from CostModelAbstractTpl< _Scalar >
typedef ActivationModelAbstractTpl< Scalar >	ActivationModelAbstract

typedef ActivationModelQuadTpl< Scalar >	ActivationModelQuad

typedef CostDataAbstractTpl< Scalar >	CostDataAbstract

typedef DataCollectorAbstractTpl< Scalar >	DataCollectorAbstract

typedef MathBaseTpl< Scalar >	MathBase

typedef MathBase::MatrixXs	MatrixXs

typedef ResidualModelAbstractTpl< Scalar >	ResidualModelAbstract

typedef StateAbstractTpl< Scalar >	StateAbstract

typedef MathBase::VectorXs	VectorXs

Public Member Functions
	CostModelImpulseCoPPositionTpl (boost::shared_ptr< StateMultibody > state, boost::shared_ptr< ActivationModelAbstract > activation, const FrameCoPSupport &cop_support)
	Initialize the impulse CoP cost model. More...

	CostModelImpulseCoPPositionTpl (boost::shared_ptr< StateMultibody > state, const FrameCoPSupport &cop_support)
	Initialize the impulse CoP cost model. More...

Public Member Functions inherited from CostModelResidualTpl< _Scalar >
	CostModelResidualTpl (boost::shared_ptr< typename Base::StateAbstract > state, boost::shared_ptr< ActivationModelAbstract > activation, boost::shared_ptr< ResidualModelAbstract > residual)
	Initialize the residual cost model. More...

	CostModelResidualTpl (boost::shared_ptr< typename Base::StateAbstract > state, boost::shared_ptr< ResidualModelAbstract > residual)
	Initialize the residual cost model. More...

virtual void	calc (const boost::shared_ptr< CostDataAbstract > &data, const Eigen::Ref< const VectorXs > &x)
	Compute the residual cost based on state only. More...

virtual void	calc (const boost::shared_ptr< CostDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u)
	Compute the residual cost. More...

virtual void	calcDiff (const boost::shared_ptr< CostDataAbstract > &data, const Eigen::Ref< const VectorXs > &x)
	Compute the derivatives of the residual cost with respect to the state only. More...

virtual void	calcDiff (const boost::shared_ptr< CostDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u)
	Compute the derivatives of the residual cost. More...

virtual boost::shared_ptr< CostDataAbstract >	createData (DataCollectorAbstract *const data)
	Create the residual cost data.

virtual void	print (std::ostream &os) const
	Print relevant information of the cost-residual model. More...

Public Member Functions inherited from CostModelAbstractTpl< _Scalar >
	CostModelAbstractTpl (boost::shared_ptr< StateAbstract > state, boost::shared_ptr< ActivationModelAbstract > activation)
	Initialize the cost model. More...

	CostModelAbstractTpl (boost::shared_ptr< StateAbstract > state, boost::shared_ptr< ActivationModelAbstract > activation, boost::shared_ptr< ResidualModelAbstract > residual)
	Initialize the cost model. More...

	CostModelAbstractTpl (boost::shared_ptr< StateAbstract > state, boost::shared_ptr< ActivationModelAbstract > activation, const std::size_t nu)
	Initialize the cost model. More...

	CostModelAbstractTpl (boost::shared_ptr< StateAbstract > state, boost::shared_ptr< ResidualModelAbstract > residual)
	Initialize the cost model. More...

	CostModelAbstractTpl (boost::shared_ptr< StateAbstract > state, const std::size_t nr)
	Initialize the cost model. More...

	CostModelAbstractTpl (boost::shared_ptr< StateAbstract > state, const std::size_t nr, const std::size_t nu)
	Initialize the cost model. More...

const boost::shared_ptr< ActivationModelAbstract > &	get_activation () const
	Return the activation model.

std::size_t	get_nu () const
	Return the dimension of the control input.

template<class ReferenceType >
ReferenceType	get_reference ()
	Return the cost reference.

const boost::shared_ptr< ResidualModelAbstract > &	get_residual () const
	Return the residual model.

const boost::shared_ptr< StateAbstract > &	get_state () const
	Return the state.

template<class ReferenceType >
void	set_reference (ReferenceType ref)
	Modify the cost reference.

Public Attributes
EIGEN_MAKE_ALIGNED_OPERATOR_NEW typedef _Scalar	Scalar

Public Attributes inherited from CostModelResidualTpl< _Scalar >
EIGEN_MAKE_ALIGNED_OPERATOR_NEW typedef _Scalar	Scalar

Public Attributes inherited from CostModelAbstractTpl< _Scalar >
EIGEN_MAKE_ALIGNED_OPERATOR_NEW typedef _Scalar	Scalar

Protected Member Functions
virtual void	get_referenceImpl (const std::type_info &ti, void *pv)
	Modify the frame CoP support.

virtual void	set_referenceImpl (const std::type_info &ti, const void *pv)
	Return the frame CoP support.

Protected Attributes
boost::shared_ptr< ActivationModelAbstract >	activation_
	Activation model.

std::size_t	nu_
	Control dimension.

boost::shared_ptr< ResidualModelAbstract >	residual_
	Residual model.

boost::shared_ptr< StateAbstract >	state_
	State description.

Protected Attributes inherited from CostModelResidualTpl< _Scalar >
boost::shared_ptr< ActivationModelAbstract >	activation_
	Activation model.

std::size_t	nu_
	Control dimension.

boost::shared_ptr< ResidualModelAbstract >	residual_
	Residual model.

boost::shared_ptr< StateAbstract >	state_
	State description.

VectorXs	unone_
	No control vector.

Protected Attributes inherited from CostModelAbstractTpl< _Scalar >
boost::shared_ptr< ActivationModelAbstract >	activation_
	Activation model.

std::size_t	nu_
	Control dimension.

boost::shared_ptr< ResidualModelAbstract >	residual_
	Residual model.

boost::shared_ptr< StateAbstract >	state_
	State description.

VectorXs	unone_
	No control vector.

Detailed Description

template<typename _Scalar>
class crocoddyl::CostModelImpulseCoPPositionTpl< _Scalar >

Define a center of pressure cost function.

It builds a cost function that bounds the center of pressure (CoP) for one contact surface to lie inside a certain geometric area defined around the reference contact frame. The cost residual vector is described as \(\mathbf{r}=\mathbf{A}\boldsymbol{\lambda}\geq\mathbf{0}\), where

\[ \mathbf{A}= \begin{bmatrix} 0 & 0 & X/2 & 0 & -1 & 0 \\ 0 & 0 & X/2 & 0 & 1 & 0 \\ 0 & 0 & Y/2 & 1 & 0 & 0 \\ 0 & 0 & Y/2 & -1 & 0 & 0 \end{bmatrix} \]

is the inequality matrix and \(\boldsymbol{\lambda}\) is the reference spatial contact force in the frame coordinate. The CoP lies inside the convex hull of the foot, see eq.(18-19) of https://hal.archives-ouvertes.fr/hal-02108449/document is we have:

\[ \begin{align}\begin{split}\tau^x &\leq Yf^z \\-\tau^x &\leq Yf^z \\\tau^y &\leq Yf^z \\-\tau^y &\leq Yf^z \end{split}\end{align} \]

with \(\boldsymbol{\lambda}= \begin{bmatrix}f^x & f^y & f^z & \tau^x & \tau^y & \tau^z \end{bmatrix}^T\).

The cost is computed, from the residual vector \(\mathbf{r}\), through an user defined activation model. Additionally, the contact frame id, the desired support region for the CoP and the inequality matrix are handled within FrameCoPSupportTpl. The force vector \(\boldsymbol{\lambda}\) and its derivatives are computed by ActionModelImpulseFwdDynamicsTpl. These values are stored in a shared data (i.e. DataCollectorImpulseTpl). Note that this cost function cannot be used with other action models.

See also: ActionModelImpulseFwdDynamicsTpl, DataCollectorImpulseTpl, ActivationModelAbstractTpl, calc(), calcDiff(), createData()

Definition at line 59 of file impulse-cop-position.hpp.

Constructor & Destructor Documentation

◆ CostModelImpulseCoPPositionTpl() [1/2]

CostModelImpulseCoPPositionTpl	(	boost::shared_ptr< StateMultibody >	state,
		boost::shared_ptr< ActivationModelAbstract >	activation,
		const FrameCoPSupport &	cop_support
	)

Initialize the impulse CoP cost model.

Parameters

[in]	state	State of the multibody system
[in]	activation	Activation model
[in]	cop_support	Id of contact frame and support region of the CoP

◆ CostModelImpulseCoPPositionTpl() [2/2]

CostModelImpulseCoPPositionTpl	(	boost::shared_ptr< StateMultibody >	state,
		const FrameCoPSupport &	cop_support
	)

Initialize the impulse CoP cost model.

We use as default activation model a quadratic barrier ActivationModelQuadraticBarrierTpl, with 0 and inf as lower and upper bounds, respectively.

Parameters

[in]	state	State of the multibody system
[in]	cop_support	Id of contact frame and support region of the cop

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

include/crocoddyl/multibody/costs/impulse-cop-position.hpp

Public Types

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

template<typename _Scalar> class crocoddyl::CostModelImpulseCoPPositionTpl< _Scalar >

Constructor & Destructor Documentation

◆ CostModelImpulseCoPPositionTpl() [1/2]

◆ CostModelImpulseCoPPositionTpl() [2/2]

template<typename _Scalar>
class crocoddyl::CostModelImpulseCoPPositionTpl< _Scalar >