Crocoddyl
ResidualModelContactCoPPositionTpl< _Scalar > Class Template Reference

Center of pressure residual function. More...

#include <contact-cop-position.hpp>

Inheritance diagram for ResidualModelContactCoPPositionTpl< _Scalar >:
ResidualModelAbstractTpl< _Scalar >

Public Types

typedef ResidualModelAbstractTpl< Scalar > Base
 
typedef CoPSupportTpl< Scalar > CoPSupport
 
typedef ResidualDataContactCoPPositionTpl< Scalar > Data
 
typedef DataCollectorAbstractTpl< Scalar > DataCollectorAbstract
 
typedef MathBaseTpl< Scalar > MathBase
 
typedef MathBase::Matrix46s Matrix46
 
typedef MathBase::MatrixXs MatrixXs
 
typedef ResidualDataAbstractTpl< Scalar > ResidualDataAbstract
 
typedef StateMultibodyTpl< Scalar > StateMultibody
 
typedef MathBase::VectorXs VectorXs
 
- Public Types inherited from ResidualModelAbstractTpl< _Scalar >
typedef ActivationDataAbstractTpl< Scalar > ActivationDataAbstract
 
typedef CostDataAbstractTpl< Scalar > CostDataAbstract
 
typedef DataCollectorAbstractTpl< Scalar > DataCollectorAbstract
 
typedef MathBase::DiagonalMatrixXs DiagonalMatrixXs
 
typedef MathBaseTpl< Scalar > MathBase
 
typedef MathBase::MatrixXs MatrixXs
 
typedef ResidualDataAbstractTpl< Scalar > ResidualDataAbstract
 
typedef StateAbstractTpl< Scalar > StateAbstract
 
typedef MathBase::VectorXs VectorXs
 

Public Member Functions

 ResidualModelContactCoPPositionTpl (boost::shared_ptr< StateMultibody > state, const pinocchio::FrameIndex id, const CoPSupport &cref)
 Initialize the contact CoP residual model. More...
 
 ResidualModelContactCoPPositionTpl (boost::shared_ptr< StateMultibody > state, const pinocchio::FrameIndex id, const CoPSupport &cref, const std::size_t nu, const bool fwddyn=true)
 Initialize the contact CoP residual model. More...
 
virtual void calc (const boost::shared_ptr< ResidualDataAbstract > &data, const Eigen::Ref< const VectorXs > &x)
 Compute the residual vector for nodes that depends only on the state. More...
 
virtual void calc (const boost::shared_ptr< ResidualDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u)
 Compute the contact CoP residual. More...
 
virtual void calcDiff (const boost::shared_ptr< ResidualDataAbstract > &data, const Eigen::Ref< const VectorXs > &x)
 Compute the Jacobian of the residual functions with respect to the state only. More...
 
virtual void calcDiff (const boost::shared_ptr< ResidualDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u)
 Compute the Jacobians of the contact CoP residual. More...
 
virtual boost::shared_ptr< ResidualDataAbstractcreateData (DataCollectorAbstract *const data)
 Create the contact CoP residual data. More...
 
 DEPRECATED ("Do not use set_id, instead create a new model", void set_id(pinocchio::FrameIndex id);) void set_reference(const CoPSupport &reference)
 Modify the reference frame id. More...
 
pinocchio::FrameIndex get_id () const
 Return the reference frame id.
 
const CoPSupportget_reference () const
 Return the reference support region of CoP.
 
bool is_fwddyn () const
 Indicates if we are using the forward-dynamics (true) or inverse-dynamics (false)
 
virtual void print (std::ostream &os) const
 Print relevant information of the cop-position residual. More...
 
void updateJacobians (const boost::shared_ptr< ResidualDataAbstract > &data)
 Update the Jacobians of the contact friction cone residual. More...
 
- Public Member Functions inherited from ResidualModelAbstractTpl< _Scalar >
 ResidualModelAbstractTpl (boost::shared_ptr< StateAbstract > state, const std::size_t nr, const bool q_dependent=true, const bool v_dependent=true, const bool u_dependent=true)
 Initialize the residual model. More...
 
 ResidualModelAbstractTpl (boost::shared_ptr< StateAbstract > state, const std::size_t nr, const std::size_t nu, const bool q_dependent=true, const bool v_dependent=true, const bool u_dependent=true)
 Initialize the residual model. More...
 
virtual void calcCostDiff (const boost::shared_ptr< CostDataAbstract > &cdata, const boost::shared_ptr< ResidualDataAbstract > &rdata, const boost::shared_ptr< ActivationDataAbstract > &adata, const bool update_u=true)
 Compute the derivative of the cost function. More...
 
std::size_t get_nr () const
 Return the dimension of the residual vector.
 
std::size_t get_nu () const
 Return the dimension of the control input.
 
bool get_q_dependent () const
 Return true if the residual function depends on q.
 
const boost::shared_ptr< StateAbstract > & get_state () const
 Return the state.
 
bool get_u_dependent () const
 Return true if the residual function depends on u.
 
bool get_v_dependent () const
 Return true if the residual function depends on v.
 

Public Attributes

EIGEN_MAKE_ALIGNED_OPERATOR_NEW typedef _Scalar Scalar
 
- Public Attributes inherited from ResidualModelAbstractTpl< _Scalar >
EIGEN_MAKE_ALIGNED_OPERATOR_NEW typedef _Scalar Scalar
 

Protected Attributes

std::size_t nu_
 Control dimension.
 
boost::shared_ptr< StateAbstractstate_
 State description.
 
VectorXs unone_
 No control vector.
 
- Protected Attributes inherited from ResidualModelAbstractTpl< _Scalar >
std::size_t nr_
 Residual vector dimension.
 
std::size_t nu_
 Control dimension.
 
bool q_dependent_
 
boost::shared_ptr< StateAbstractstate_
 State description.
 
bool u_dependent_
 
VectorXs unone_
 No control vector.
 
bool v_dependent_
 

Detailed Description

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

Center of pressure residual function.

It builds a residual 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 residual 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 residual 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 CoPSupportTpl. The force vector \(\boldsymbol{\lambda}\) and its derivatives are computed by DifferentialActionModelContactFwdDynamicsTpl or ActionModelImpulseFwdDynamicTpl. These values are stored in a shared data (i.e., DataCollectorContactTpl or DataCollectorImpulseTpl). Note that this residual function cannot be used with other action models.

See also
ResidualModelAbstractTpl, calc(), calcDiff(), createData(), DifferentialActionModelContactFwdDynamicsTpl, ActionModelImpulseFwdDynamicTpl, DataCollectorForceTpl

Definition at line 68 of file contact-cop-position.hpp.

Constructor & Destructor Documentation

◆ ResidualModelContactCoPPositionTpl() [1/2]

ResidualModelContactCoPPositionTpl ( boost::shared_ptr< StateMultibody state,
const pinocchio::FrameIndex  id,
const CoPSupport cref,
const std::size_t  nu,
const bool  fwddyn = true 
)

Initialize the contact CoP residual model.

Note that for the inverse-dynamic cases, the control vector contains the generalized accelerations, torques, and all the contact forces.

Parameters
[in]stateState of the multibody system
[in]idReference frame id
[in]crefReference support region of the CoP
[in]nuDimension of control vector
[in]fwddynIndicates that we have a forward dynamics problem (true) or inverse dynamics (false)

◆ ResidualModelContactCoPPositionTpl() [2/2]

ResidualModelContactCoPPositionTpl ( boost::shared_ptr< StateMultibody state,
const pinocchio::FrameIndex  id,
const CoPSupport cref 
)

Initialize the contact CoP residual model.

The default nu value is obtained from StateAbstractTpl::get_nv(). Note that this constructor can be used for forward-dynamics cases only.

Parameters
[in]stateState of the multibody system
[in]idReference frame id
[in]crefReference support region of the CoP

Member Function Documentation

◆ calc() [1/2]

virtual void calc ( const boost::shared_ptr< ResidualDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x,
const Eigen::Ref< const VectorXs > &  u 
)
virtual

Compute the contact CoP residual.

The CoP residual is computed based on the \(\mathbf{A}\) matrix, the force vector is computed by DifferentialActionModelContactFwdDynamicsTpl or ActionModelImpulseFwdDynamicTpl which is stored in DataCollectorContactTpl or DataCollectorImpulseTpl.

Parameters
[in]dataContact CoP data
[in]xState point \(\mathbf{x}\in\mathbb{R}^{ndx}\)
[in]uControl input \(\mathbf{u}\in\mathbb{R}^{nu}\)

Reimplemented from ResidualModelAbstractTpl< _Scalar >.

◆ calc() [2/2]

virtual void calc ( const boost::shared_ptr< ResidualDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x 
)
virtual

Compute the residual vector for nodes that depends only on the state.

It updates the residual vector based on the state only (i.e., it ignores the contact forces). This function is used in the terminal nodes of an optimal control problem.

Parameters
[in]dataResidual data
[in]xState point \(\mathbf{x}\in\mathbb{R}^{ndx}\)

Reimplemented from ResidualModelAbstractTpl< _Scalar >.

◆ calcDiff() [1/2]

virtual void calcDiff ( const boost::shared_ptr< ResidualDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x,
const Eigen::Ref< const VectorXs > &  u 
)
virtual

Compute the Jacobians of the contact CoP residual.

The CoP residual is computed based on the \(\mathbf{A}\) matrix, the force vector is computed by DifferentialActionModelContactFwdDynamicsTpl or ActionModelImpulseFwdDynamicTpl which is stored in DataCollectorContactTpl or DataCollectorImpulseTpl.

Parameters
[in]dataContact CoP data
[in]xState point \(\mathbf{x}\in\mathbb{R}^{ndx}\)
[in]uControl input \(\mathbf{u}\in\mathbb{R}^{nu}\)

Reimplemented from ResidualModelAbstractTpl< _Scalar >.

◆ calcDiff() [2/2]

virtual void calcDiff ( const boost::shared_ptr< ResidualDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x 
)
virtual

Compute the Jacobian of the residual functions with respect to the state only.

It updates the Jacobian of the residual function based on the state only (i.e., it ignores the contact forces). This function is used in the terminal nodes of an optimal control problem.

Parameters
[in]dataResidual data
[in]xState point \(\mathbf{x}\in\mathbb{R}^{ndx}\)

Reimplemented from ResidualModelAbstractTpl< _Scalar >.

◆ createData()

virtual boost::shared_ptr<ResidualDataAbstract> createData ( DataCollectorAbstract *const  data)
virtual

Create the contact CoP residual data.

Each residual model has its own data that needs to be allocated. This function returns the allocated data for a predefined residual.

Parameters
[in]dataShared data (it should be of type DataCollectorContactTpl)
Returns
the residual data.

Reimplemented from ResidualModelAbstractTpl< _Scalar >.

◆ updateJacobians()

void updateJacobians ( const boost::shared_ptr< ResidualDataAbstract > &  data)

Update the Jacobians of the contact friction cone residual.

Parameters
[in]dataContact friction cone residual data

◆ DEPRECATED()

DEPRECATED ( "Do not use  set_id,
instead create a new model"  ,
void set_id(pinocchio::FrameIndex id);   
) const &

Modify the reference frame id.

Modify the reference support region of CoP

◆ print()

virtual void print ( std::ostream &  os) const
virtual

Print relevant information of the cop-position residual.

Parameters
[out]osOutput stream object

Reimplemented from ResidualModelAbstractTpl< _Scalar >.


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