Crocoddyl
 
Loading...
Searching...
No Matches
ActionModelNumDiffTpl< _Scalar > Class Template Reference

This class computes the numerical differentiation of an action model. More...

#include <action.hpp>

Inheritance diagram for ActionModelNumDiffTpl< _Scalar >:
ActionModelAbstractTpl< _Scalar > ActionModelBase

Public Types

typedef ActionDataAbstractTpl< Scalar > ActionDataAbstract
 
typedef ActionModelAbstractTpl< Scalar > Base
 
typedef ActionDataNumDiffTpl< Scalar > Data
 
typedef MathBaseTpl< Scalar > MathBase
 
typedef MathBaseTpl< Scalar >::MatrixXs MatrixXs
 
typedef MathBaseTpl< Scalar >::VectorXs VectorXs
 
- Public Types inherited from ActionModelAbstractTpl< _Scalar >
typedef ActionDataAbstractTpl< Scalar > ActionDataAbstract
 
typedef MathBaseTpl< Scalar > MathBase
 
typedef ScalarSelector< Scalar >::type ScalarType
 
typedef StateAbstractTpl< Scalar > StateAbstract
 
typedef MathBase::VectorXs VectorXs
 

Public Member Functions

 ActionModelNumDiffTpl (std::shared_ptr< Base > model, bool with_gauss_approx=false)
 Initialize the numdiff action model.
 
virtual void calc (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x) override
 
virtual void calc (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u) override
 Compute the next state and cost value.
 
virtual void calcDiff (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x) override
 
virtual void calcDiff (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u) override
 Compute the derivatives of the dynamics and cost functions.
 
template<typename NewScalar >
ActionModelNumDiffTpl< NewScalar > cast () const
 Cast the action numdiff model to a different scalar type.
 
virtual std::shared_ptr< ActionDataAbstractcreateData () override
 Create the action data.
 
const Scalar get_disturbance () const
 Return the disturbance constant used in the numerical differentiation routine.
 
const std::shared_ptr< Base > & get_model () const
 Return the acton model that we use to numerical differentiate.
 
bool get_with_gauss_approx ()
 Identify if the Gauss approximation is going to be used or not.
 
virtual void print (std::ostream &os) const override
 Print relevant information of the diff-action numdiff model.
 
virtual void quasiStatic (const std::shared_ptr< ActionDataAbstract > &data, Eigen::Ref< VectorXs > u, const Eigen::Ref< const VectorXs > &x, const std::size_t maxiter=100, const Scalar tol=Scalar(1e-9)) override
 Computes the quasic static commands.
 
void set_disturbance (const Scalar disturbance)
 Modify the disturbance constant used in the numerical differentiation routine.
 
- Public Member Functions inherited from ActionModelAbstractTpl< _Scalar >
 ActionModelAbstractTpl (const ActionModelAbstractTpl< Scalar > &other)
 Copy constructor.
 
 ActionModelAbstractTpl (std::shared_ptr< StateAbstract > state, const std::size_t nu, const std::size_t nr=0, const std::size_t ng=0, const std::size_t nh=0, const std::size_t ng_T=0, const std::size_t nh_T=0)
 Initialize the action model.
 
virtual void calc (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x)
 Compute the total cost value for nodes that depends only on the state.
 
virtual void calc (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u)=0
 Compute the next state and cost value.
 
virtual void calcDiff (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x)
 Compute the derivatives of the cost functions with respect to the state only.
 
virtual void calcDiff (const std::shared_ptr< ActionDataAbstract > &data, const Eigen::Ref< const VectorXs > &x, const Eigen::Ref< const VectorXs > &u)=0
 Compute the derivatives of the dynamics and cost functions.
 
virtual bool checkData (const std::shared_ptr< ActionDataAbstract > &data)
 Checks that a specific data belongs to this model.
 
virtual const VectorXs & get_g_lb () const
 Return the lower bound of the inequality constraints.
 
virtual const VectorXs & get_g_ub () const
 Return the upper bound of the inequality constraints.
 
bool get_has_control_limits () const
 Indicates if there are defined control limits.
 
virtual std::size_t get_ng () const
 Return the number of inequality constraints.
 
virtual std::size_t get_ng_T () const
 Return the number of inequality terminal constraints.
 
virtual std::size_t get_nh () const
 Return the number of equality constraints.
 
virtual std::size_t get_nh_T () const
 Return the number of equality terminal constraints.
 
std::size_t get_nr () const
 Return the dimension of the cost-residual vector.
 
std::size_t get_nu () const
 Return the dimension of the control input.
 
const std::shared_ptr< StateAbstract > & get_state () const
 Return the state.
 
const VectorXs & get_u_lb () const
 Return the control lower bound.
 
const VectorXs & get_u_ub () const
 Return the control upper bound.
 
virtual void quasiStatic (const std::shared_ptr< ActionDataAbstract > &data, Eigen::Ref< VectorXs > u, const Eigen::Ref< const VectorXs > &x, const std::size_t maxiter=100, const Scalar tol=Scalar(1e-9))
 Computes the quasic static commands.
 
VectorXs quasiStatic_x (const std::shared_ptr< ActionDataAbstract > &data, const VectorXs &x, const std::size_t maxiter=100, const Scalar tol=Scalar(1e-9))
 
void set_g_lb (const VectorXs &g_lb)
 Modify the lower bound of the inequality constraints.
 
void set_g_ub (const VectorXs &g_ub)
 Modify the upper bound of the inequality constraints.
 
void set_u_lb (const VectorXs &u_lb)
 Modify the control lower bounds.
 
void set_u_ub (const VectorXs &u_ub)
 Modify the control upper bounds.
 

Public Attributes

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

Protected Attributes

bool has_control_limits_
 
std::size_t nr_
 
std::size_t nu_
 < Dimension of the cost residual
 
std::shared_ptr< StateAbstractstate_
 < Control dimension
 
VectorXs u_lb_
 < Model of the state
 
VectorXs u_ub_
 < Lower control limits
 
- Protected Attributes inherited from ActionModelAbstractTpl< _Scalar >
VectorXs g_lb_
 Lower bound of the inequality constraints.
 
VectorXs g_ub_
 Lower bound of the inequality constraints.
 
bool has_control_limits_
 
std::size_t ng_
 Number of inequality constraints.
 
std::size_t ng_T_
 Number of inequality terminal constraints.
 
std::size_t nh_
 Number of equality constraints.
 
std::size_t nh_T_
 Number of equality terminal constraints.
 
std::size_t nr_
 Dimension of the cost residual.
 
std::size_t nu_
 Control dimension.
 
std::shared_ptr< StateAbstractstate_
 Model of the state.
 
VectorXs u_lb_
 Lower control limits.
 
VectorXs u_ub_
 Upper control limits.
 
VectorXs unone_
 Neutral state.
 

Additional Inherited Members

- Protected Member Functions inherited from ActionModelAbstractTpl< _Scalar >
void update_has_control_limits ()
 Update the status of the control limits (i.e. if there are defined limits)
 

Detailed Description

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

This class computes the numerical differentiation of an action model.

It computes the Jacobian of the cost, its residual and dynamics via numerical differentiation. It considers that the action model owns a cost residual and the cost is the square of this residual, i.e., \(\ell(\mathbf{x},\mathbf{u})=\frac{1}{2}\|\mathbf{r}(\mathbf{x},\mathbf{u})\|^2\), where \(\mathbf{r}(\mathbf{x},\mathbf{u})\) is the residual vector. The Hessian is computed only through the Gauss-Newton approximation, i.e.,

\begin{eqnarray*} \mathbf{\ell}_\mathbf{xx} &=& \mathbf{R_x}^T\mathbf{R_x} \\ \mathbf{\ell}_\mathbf{uu} &=& \mathbf{R_u}^T\mathbf{R_u} \\ \mathbf{\ell}_\mathbf{xu} &=& \mathbf{R_x}^T\mathbf{R_u} \end{eqnarray*}

where the Jacobians of the cost residuals are denoted by \(\mathbf{R_x}\) and \(\mathbf{R_u}\). Note that this approximation ignores the tensor products (e.g., \(\mathbf{R_{xx}}\mathbf{r}\)).

Finally, in the case that the cost does not have a residual, we set the Hessian to zero, i.e., \(\mathbf{L_{xx}} = \mathbf{L_{xu}} = \mathbf{L_{uu}} = \mathbf{0}\).

See also
ActionModelAbstractTpl(), calcDiff()

Definition at line 44 of file action.hpp.

Member Typedef Documentation

◆ ActionDataAbstract

template<typename _Scalar >
typedef ActionDataAbstractTpl<Scalar> ActionDataAbstract

Definition at line 50 of file action.hpp.

◆ Base

template<typename _Scalar >
typedef ActionModelAbstractTpl<Scalar> Base

Definition at line 51 of file action.hpp.

◆ Data

template<typename _Scalar >
typedef ActionDataNumDiffTpl<Scalar> Data

Definition at line 52 of file action.hpp.

◆ MathBase

template<typename _Scalar >
typedef MathBaseTpl<Scalar> MathBase

Definition at line 53 of file action.hpp.

◆ VectorXs

template<typename _Scalar >
typedef MathBaseTpl<Scalar>::VectorXs VectorXs

Definition at line 54 of file action.hpp.

◆ MatrixXs

template<typename _Scalar >
typedef MathBaseTpl<Scalar>::MatrixXs MatrixXs

Definition at line 55 of file action.hpp.

Constructor & Destructor Documentation

◆ ActionModelNumDiffTpl()

template<typename _Scalar >
ActionModelNumDiffTpl ( std::shared_ptr< Base model,
bool  with_gauss_approx = false 
)
explicit

Initialize the numdiff action model.

Parameters
[in]modelAction model that we want to apply the numerical differentiation
[in]with_gauss_approxTrue if we want to use the Gauss approximation for computing the Hessians

Member Function Documentation

◆ calc() [1/2]

template<typename _Scalar >
virtual void calc ( const std::shared_ptr< ActionDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x,
const Eigen::Ref< const VectorXs > &  u 
)
overridevirtual

Compute the next state and cost value.

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

◆ calc() [2/2]

template<typename _Scalar >
virtual void calc ( const std::shared_ptr< ActionDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x 
)
overridevirtual

◆ calcDiff() [1/2]

template<typename _Scalar >
virtual void calcDiff ( const std::shared_ptr< ActionDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x,
const Eigen::Ref< const VectorXs > &  u 
)
overridevirtual

Compute the derivatives of the dynamics and cost functions.

It computes the partial derivatives of the dynamical system and the cost function. It assumes that calc() has been run first. This function builds a linear-quadratic approximation of the action model (i.e. dynamical system and cost function).

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

◆ calcDiff() [2/2]

template<typename _Scalar >
virtual void calcDiff ( const std::shared_ptr< ActionDataAbstract > &  data,
const Eigen::Ref< const VectorXs > &  x 
)
overridevirtual

◆ createData()

template<typename _Scalar >
virtual std::shared_ptr< ActionDataAbstract > createData ( )
overridevirtual

Create the action data.

Returns
the action data

Reimplemented from ActionModelAbstractTpl< _Scalar >.

◆ quasiStatic()

template<typename _Scalar >
virtual void quasiStatic ( const std::shared_ptr< ActionDataAbstract > &  data,
Eigen::Ref< VectorXs >  u,
const Eigen::Ref< const VectorXs > &  x,
const std::size_t  maxiter = 100,
const Scalar  tol = Scalar(1e-9) 
)
overridevirtual

Computes the quasic static commands.

The quasic static commands are the ones produced for a the reference posture as an equilibrium point, i.e. for \(\mathbf{f^q_x}\delta\mathbf{q}+\mathbf{f_u}\delta\mathbf{u}=\mathbf{0}\)

Parameters
[in]dataAction data
[out]uQuasic static commands
[in]xState point (velocity has to be zero)
[in]maxiterMaximum allowed number of iterations
[in]tolTolerance

◆ cast()

template<typename _Scalar >
template<typename NewScalar >
ActionModelNumDiffTpl< NewScalar > cast ( ) const

Cast the action numdiff model to a different scalar type.

It is useful for operations requiring different precision or scalar types.

Template Parameters
NewScalarThe new scalar type to cast to.
Returns
ActionModelNumDiffTpl<NewScalar> An action model with the new scalar type.

◆ print()

template<typename _Scalar >
virtual void print ( std::ostream &  os) const
overridevirtual

Print relevant information of the diff-action numdiff model.

Parameters
[out]osOutput stream object

Reimplemented from ActionModelAbstractTpl< _Scalar >.

Member Data Documentation

◆ Scalar

template<typename _Scalar >
EIGEN_MAKE_ALIGNED_OPERATOR_NEW typedef _Scalar Scalar

Definition at line 49 of file action.hpp.

◆ has_control_limits_

template<typename _Scalar >
bool has_control_limits_
protected

Indicates whether any of the control limits is finite

Definition at line 340 of file action-base.hpp.

◆ nr_

template<typename _Scalar >
std::size_t nr_
protected

< Indicates whether any of the control limits

Definition at line 329 of file action-base.hpp.

◆ nu_

template<typename _Scalar >
std::size_t nu_
protected

< Dimension of the cost residual

Definition at line 328 of file action-base.hpp.

◆ state_

template<typename _Scalar >
std::shared_ptr<StateAbstract> state_
protected

< Control dimension

Definition at line 334 of file action-base.hpp.

◆ u_lb_

template<typename _Scalar >
VectorXs u_lb_
protected

< Model of the state

Definition at line 338 of file action-base.hpp.

◆ u_ub_

template<typename _Scalar >
VectorXs u_ub_
protected

< Lower control limits

Definition at line 339 of file action-base.hpp.


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