Form of the lagged friction disapative potential and forces. More...

#include <FrictionForm.hpp>

Inheritance diagram for polyfem::solver::FrictionForm:

Collaboration diagram for polyfem::solver::FrictionForm:

Public Member Functions
	FrictionForm (const ipc::CollisionMesh &collision_mesh, const std::shared_ptr< time_integrator::ImplicitTimeIntegrator > time_integrator, const double epsv, const double mu, const ipc::BroadPhaseMethod broad_phase_method, const ContactForm &contact_form, const int n_lagging_iters)
	Construct a new Friction Form object.

std::string	name () const override

void	force_shape_derivative (const Eigen::MatrixXd &prev_solution, const Eigen::MatrixXd &solution, const Eigen::MatrixXd &adjoint, const ipc::FrictionCollisions &friction_constraints_set, Eigen::VectorXd &term)

void	init_lagging (const Eigen::VectorXd &x) override
	Initialize lagged fields.

void	update_lagging (const Eigen::VectorXd &x, const int iter_num) override
	Update lagged fields.

void	update_lagging (const Eigen::VectorXd &x)
	Update lagged fields.

int	max_lagging_iterations () const override
	Get the maximum number of lagging iteration allowable.

bool	uses_lagging () const override
	Does this form require lagging?

Eigen::MatrixXd	compute_displaced_surface (const Eigen::VectorXd &x) const
	Compute the displaced positions of the surface nodes.

Eigen::MatrixXd	compute_surface_velocities (const Eigen::VectorXd &x) const
	Compute the surface velocities.

double	dv_dx () const
	Compute the derivative of the velocities wrt x.

double	mu () const

double	epsv () const

const ipc::FrictionCollisions &	friction_collision_set () const

const ipc::FrictionPotential &	friction_potential () const

Public Member Functions inherited from polyfem::solver::Form
virtual	~Form ()

virtual void	init (const Eigen::VectorXd &x)
	Initialize the form.

virtual void	finish ()

virtual double	value (const Eigen::VectorXd &x) const
	Compute the value of the form multiplied with the weigth.

Eigen::VectorXd	value_per_element (const Eigen::VectorXd &x) const
	Compute the value of the form multiplied with the weigth.

virtual void	first_derivative (const Eigen::VectorXd &x, Eigen::VectorXd &gradv) const
	Compute the first derivative of the value wrt x multiplied with the weigth.

void	second_derivative (const Eigen::VectorXd &x, StiffnessMatrix &hessian) const
	Compute the second derivative of the value wrt x multiplied with the weigth.

virtual bool	is_step_valid (const Eigen::VectorXd &x0, const Eigen::VectorXd &x1) const
	Determine if a step from solution x0 to solution x1 is allowed.

virtual double	max_step_size (const Eigen::VectorXd &x0, const Eigen::VectorXd &x1) const
	Determine the maximum step size allowable between the current and next solution.

virtual void	line_search_begin (const Eigen::VectorXd &x0, const Eigen::VectorXd &x1)
	Initialize variables used during the line search.

virtual void	line_search_end ()
	Clear variables used during the line search.

virtual void	post_step (const polysolve::nonlinear::PostStepData &data)
	Update fields after a step in the optimization.

virtual void	solution_changed (const Eigen::VectorXd &new_x)
	Update cached fields upon a change in the solution.

virtual void	update_quantities (const double t, const Eigen::VectorXd &x)
	Update time-dependent fields.

void	set_project_to_psd (bool val)
	Set project to psd.

bool	is_project_to_psd () const
	Get if the form's second derivative is projected to psd.

void	enable ()
	Enable the form.

void	disable ()
	Disable the form.

void	set_enabled (const bool enabled)
	Set if the form is enabled.

bool	enabled () const
	Determine if the form is enabled.

virtual double	weight () const
	Get the form's multiplicative constant weight.

void	set_weight (const double weight)
	Set the form's multiplicative constant weight.

virtual bool	is_step_collision_free (const Eigen::VectorXd &x0, const Eigen::VectorXd &x1) const
	Checks if the step is collision free.

void	set_output_dir (const std::string &output_dir)

Protected Member Functions
double	value_unweighted (const Eigen::VectorXd &x) const override
	Compute the value of the form.

void	first_derivative_unweighted (const Eigen::VectorXd &x, Eigen::VectorXd &gradv) const override
	Compute the first derivative of the value wrt x.

void	second_derivative_unweighted (const Eigen::VectorXd &x, StiffnessMatrix &hessian) const override
	Compute the second derivative of the value wrt x.

Protected Member Functions inherited from polyfem::solver::Form
std::string	resolve_output_path (const std::string &path) const

virtual Eigen::VectorXd	value_per_element_unweighted (const Eigen::VectorXd &x) const
	Compute the value of the form multiplied per element.

Private Attributes
const ipc::CollisionMesh &	collision_mesh_
	Reference to the collision mesh.

const std::shared_ptr< time_integrator::ImplicitTimeIntegrator >	time_integrator_
	Pointer to the time integrator.

const double	epsv_
	Smoothing factor between static and dynamic friction.

const double	mu_
	Global coefficient of friction.

const ipc::BroadPhaseMethod	broad_phase_method_
	Broad-phase method used for distance computation and collision detection.

const int	n_lagging_iters_
	Number of lagging iterations.

ipc::FrictionCollisions	friction_collision_set_
	Lagged friction constraint set.

const ContactForm &	contact_form_
	necessary to have the barrier stiffnes, maybe clean me

const ipc::FrictionPotential	friction_potential_

Additional Inherited Members
Protected Attributes inherited from polyfem::solver::Form
bool	project_to_psd_ = false
	If true, the form's second derivative is projected to be positive semidefinite.

double	weight_ = 1
	weight of the form (e.g., AL penalty weight or Δt²)

bool	enabled_ = true
	If true, the form is enabled.

std::string	output_dir_

Detailed Description

Form of the lagged friction disapative potential and forces.

Definition at line 18 of file FrictionForm.hpp.

Constructor & Destructor Documentation

◆ FrictionForm()

polyfem::solver::FrictionForm::FrictionForm	(	const ipc::CollisionMesh &	collision_mesh,
		const std::shared_ptr< time_integrator::ImplicitTimeIntegrator >	time_integrator,
		const double	epsv,
		const double	mu,
		const ipc::BroadPhaseMethod	broad_phase_method,
		const ContactForm &	contact_form,
		const int	n_lagging_iters
	)

Construct a new Friction Form object.

Parameters

collision_mesh	Reference to the collision mesh
time_integrator	Pointer to the time integrator
epsv	Smoothing factor between static and dynamic friction
mu	Global coefficient of friction
dhat	Barrier activation distance
broad_phase_method	Broad-phase method used for distance computation and collision detection
contact_form	Pointer to contact form; necessary to have the barrier stiffnes, maybe clean me
n_lagging_iters	Number of lagging iterations

Definition at line 9 of file FrictionForm.cpp.

References epsv_.

Member Function Documentation

◆ compute_displaced_surface()

Eigen::MatrixXd polyfem::solver::FrictionForm::compute_displaced_surface ( const Eigen::VectorXd & x ) const

Compute the displaced positions of the surface nodes.

Definition at line 88 of file FrictionForm.cpp.

References polyfem::solver::ContactForm::compute_displaced_surface(), contact_form_, and x.

Referenced by update_lagging().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ compute_surface_velocities()

Eigen::MatrixXd polyfem::solver::FrictionForm::compute_surface_velocities ( const Eigen::VectorXd & x ) const

Compute the surface velocities.

Definition at line 93 of file FrictionForm.cpp.

References collision_mesh_, time_integrator_, polyfem::utils::unflatten(), and x.

Referenced by first_derivative_unweighted(), second_derivative_unweighted(), and value_unweighted().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ dv_dx()

double polyfem::solver::FrictionForm::dv_dx ( ) const

Compute the derivative of the velocities wrt x.

Definition at line 100 of file FrictionForm.cpp.

References time_integrator_.

Referenced by second_derivative_unweighted(), and value_unweighted().

Here is the caller graph for this function:

◆ epsv()

double polyfem::solver::FrictionForm::epsv ( ) const

inline

Definition at line 87 of file FrictionForm.hpp.

References epsv_.

◆ first_derivative_unweighted()

void polyfem::solver::FrictionForm::first_derivative_unweighted	(	const Eigen::VectorXd &	x,
		Eigen::VectorXd &	gradv
	)		const

overrideprotectedvirtual

Compute the first derivative of the value wrt x.

Parameters

[in]	x	Current solution
[out]	gradv	Output gradient of the value wrt x

Implements polyfem::solver::Form.

Definition at line 110 of file FrictionForm.cpp.

References collision_mesh_, compute_surface_velocities(), friction_collision_set_, friction_potential_, and x.

Here is the call graph for this function:

◆ force_shape_derivative()

void polyfem::solver::FrictionForm::force_shape_derivative	(	const Eigen::MatrixXd &	prev_solution,
		const Eigen::MatrixXd &	solution,
		const Eigen::MatrixXd &	adjoint,
		const ipc::FrictionCollisions &	friction_constraints_set,
		Eigen::VectorXd &	term
	)

Definition at line 29 of file FrictionForm.cpp.

References polyfem::solver::ContactForm::barrier_potential(), polyfem::solver::ContactForm::barrier_stiffness(), collision_mesh_, contact_form_, friction_potential_, time_integrator_, and polyfem::utils::unflatten().

Here is the call graph for this function:

◆ friction_collision_set()

const ipc::FrictionCollisions & polyfem::solver::FrictionForm::friction_collision_set ( ) const

inline

Definition at line 88 of file FrictionForm.hpp.

References friction_collision_set_.

◆ friction_potential()

const ipc::FrictionPotential & polyfem::solver::FrictionForm::friction_potential ( ) const

inline

Definition at line 89 of file FrictionForm.hpp.

References friction_potential_.

◆ init_lagging()

void polyfem::solver::FrictionForm::init_lagging ( const Eigen::VectorXd & x )

inlineoverridevirtual

Initialize lagged fields.

Parameters

x	Current solution

Reimplemented from polyfem::solver::Form.

Definition at line 62 of file FrictionForm.hpp.

References update_lagging(), and x.

Here is the call graph for this function:

◆ max_lagging_iterations()

int polyfem::solver::FrictionForm::max_lagging_iterations ( ) const

inlineoverridevirtual

Get the maximum number of lagging iteration allowable.

Reimplemented from polyfem::solver::Form.

Definition at line 73 of file FrictionForm.hpp.

References n_lagging_iters_.

◆ mu()

double polyfem::solver::FrictionForm::mu ( ) const

inline

Definition at line 86 of file FrictionForm.hpp.

References mu_.

◆ name()

std::string polyfem::solver::FrictionForm::name ( ) const

inlineoverridevirtual

Implements polyfem::solver::Form.

Definition at line 39 of file FrictionForm.hpp.

◆ second_derivative_unweighted()

void polyfem::solver::FrictionForm::second_derivative_unweighted	(	const Eigen::VectorXd &	x,
		StiffnessMatrix &	hessian
	)		const

overrideprotectedvirtual

Compute the second derivative of the value wrt x.

Parameters

[in]	x	Current solution
[out]	hessian	Output Hessian of the value wrt x

Implements polyfem::solver::Form.

Definition at line 117 of file FrictionForm.cpp.

References collision_mesh_, compute_surface_velocities(), dv_dx(), friction_collision_set_, friction_potential_, POLYFEM_SCOPED_TIMER, polyfem::solver::Form::project_to_psd_, and x.

Here is the call graph for this function:

◆ update_lagging() [1/2]

void polyfem::solver::FrictionForm::update_lagging ( const Eigen::VectorXd & x )

inline

Update lagged fields.

Parameters

x	Current solution

Definition at line 70 of file FrictionForm.hpp.

References update_lagging(), and x.

Referenced by update_lagging().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ update_lagging() [2/2]

void polyfem::solver::FrictionForm::update_lagging	(	const Eigen::VectorXd &	x,
		const int	iter_num
	)

overridevirtual

Update lagged fields.

Parameters

x	Current solution

Reimplemented from polyfem::solver::Form.

Definition at line 127 of file FrictionForm.cpp.

References polyfem::solver::ContactForm::barrier_potential(), polyfem::solver::ContactForm::barrier_stiffness(), broad_phase_method_, collision_mesh_, compute_displaced_surface(), contact_form_, polyfem::solver::ContactForm::dhat(), polyfem::solver::ContactForm::enable_shape_derivatives(), friction_collision_set_, mu_, polyfem::solver::ContactForm::use_convergent_formulation(), and x.

Referenced by init_lagging().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ uses_lagging()

bool polyfem::solver::FrictionForm::uses_lagging ( ) const

inlineoverridevirtual

Does this form require lagging?

Returns: True if the form requires lagging

Reimplemented from polyfem::solver::Form.

Definition at line 77 of file FrictionForm.hpp.

◆ value_unweighted()

double polyfem::solver::FrictionForm::value_unweighted ( const Eigen::VectorXd & x ) const

overrideprotectedvirtual

Compute the value of the form.

Parameters

x	Current solution

Returns: Computed value

Implements polyfem::solver::Form.

Definition at line 105 of file FrictionForm.cpp.

References collision_mesh_, compute_surface_velocities(), dv_dx(), friction_collision_set_, friction_potential_, and x.

Here is the call graph for this function:

Member Data Documentation

◆ broad_phase_method_

const ipc::BroadPhaseMethod polyfem::solver::FrictionForm::broad_phase_method_

private

Broad-phase method used for distance computation and collision detection.

Definition at line 100 of file FrictionForm.hpp.

Referenced by update_lagging().

◆ collision_mesh_

const ipc::CollisionMesh& polyfem::solver::FrictionForm::collision_mesh_

private

Reference to the collision mesh.

Definition at line 93 of file FrictionForm.hpp.

Referenced by compute_surface_velocities(), first_derivative_unweighted(), force_shape_derivative(), second_derivative_unweighted(), update_lagging(), and value_unweighted().

◆ contact_form_

const ContactForm& polyfem::solver::FrictionForm::contact_form_

private

necessary to have the barrier stiffnes, maybe clean me

Definition at line 105 of file FrictionForm.hpp.

Referenced by compute_displaced_surface(), force_shape_derivative(), and update_lagging().

◆ epsv_

const double polyfem::solver::FrictionForm::epsv_

private

Smoothing factor between static and dynamic friction.

Definition at line 98 of file FrictionForm.hpp.

Referenced by epsv(), and FrictionForm().

◆ friction_collision_set_

ipc::FrictionCollisions polyfem::solver::FrictionForm::friction_collision_set_

private

Lagged friction constraint set.

Definition at line 103 of file FrictionForm.hpp.

Referenced by first_derivative_unweighted(), friction_collision_set(), second_derivative_unweighted(), update_lagging(), and value_unweighted().

◆ friction_potential_

const ipc::FrictionPotential polyfem::solver::FrictionForm::friction_potential_

private

Definition at line 107 of file FrictionForm.hpp.

Referenced by first_derivative_unweighted(), force_shape_derivative(), friction_potential(), second_derivative_unweighted(), and value_unweighted().

◆ mu_

const double polyfem::solver::FrictionForm::mu_

private

Global coefficient of friction.

Definition at line 99 of file FrictionForm.hpp.

Referenced by mu(), and update_lagging().

◆ n_lagging_iters_

const int polyfem::solver::FrictionForm::n_lagging_iters_

private

Number of lagging iterations.

Definition at line 101 of file FrictionForm.hpp.

Referenced by max_lagging_iterations().

◆ time_integrator_

const std::shared_ptr<time_integrator::ImplicitTimeIntegrator> polyfem::solver::FrictionForm::time_integrator_

private

Pointer to the time integrator.

Definition at line 96 of file FrictionForm.hpp.

Referenced by compute_surface_velocities(), dv_dx(), and force_shape_derivative().

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

src/polyfem/solver/forms/FrictionForm.hpp
src/polyfem/solver/forms/FrictionForm.cpp

Public Member Functions

Protected Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ FrictionForm()

Member Function Documentation

◆ compute_displaced_surface()

◆ compute_surface_velocities()

◆ dv_dx()

◆ epsv()

◆ first_derivative_unweighted()

◆ force_shape_derivative()

◆ friction_collision_set()

◆ friction_potential()

◆ init_lagging()

◆ max_lagging_iterations()

◆ mu()

◆ name()

◆ second_derivative_unweighted()

◆ update_lagging() [1/2]

◆ update_lagging() [2/2]

◆ uses_lagging()

◆ value_unweighted()

Member Data Documentation

◆ broad_phase_method_

◆ collision_mesh_

◆ contact_form_

◆ epsv_

◆ friction_collision_set_

◆ friction_potential_

◆ mu_

◆ n_lagging_iters_

◆ time_integrator_