A class representing a deformable particle simulated using the Finite Element Method (FEM). More...

#include <deformable_particle.hpp>

Inheritance diagram for netdem::DeformableParticle:

Public Member Functions
	DeformableParticle ()
	Constructs a new `DeformableParticle` object.

Particle *	Clone () const override
	Creates a new instance of this object.

void	SetShape (Shape *s) override
	Sets the shape of the particle.

void	InitFEMMesh ()
	Initialized the mesh for FEM analysis.

void	SetDensity (double dens) override
	Sets the density of the particle.

void	SetPosition (double x, double y, double z) override
	Sets the position of the particle.

void	SetRodrigues (double angle, double axis_x, double axis_y, double axis_z) override
	Sets the angle and axis of rotation for the particle.

void	SetQuaternion (double q_0, double q_1, double q_2, double q_3) override
	Sets the orientation of the particle using a quaternion.

void	SetVelocity (double v_x, double v_y, double v_z) override
	Sets the velocity of the particle.

Vec3d	GetVelocity (Vec3d const &pos) override
	Gets the velocity of the particle at a given position.

void	AddForce (int node_id, Vec3d const &f)
	Adds a force to a node on the particle's mesh.

void	ClearForce () override
	Clears all forces on the particle's mesh.

void	ApplyContactForce (ContactPP const *cnt) override
	Applies a contact force to the particle.

void	ApplyContactForce (ContactPW const *cnt) override
	Applies a contact force between a particle and a wall.

void	UpdateMotion (double dt) override
	Updates the motion of the particle.

void	UpdateShape ()
	Updates the shape of the particle.

void	UpdateBoundFast () override
	Updates the bounding box of the particle.

void	UpdateBound () override
	Updates the bounding box of the particle.

void	SaveSurfaceAsVTK (std::string const &filename)
	Saves the surface of the particle as a VTK file.

void	SaveAsVTK (std::string const &filename) override
	Saves the particle as a VTK file.

	~DeformableParticle () override
	Destroys the `DeformableParticle` object and frees any memory used by it.

Public Member Functions inherited from netdem::Particle
	Particle ()
	Default constructor for the Particle class.

	Particle (Shape *const shape)
	Constructor for the Particle class which specifies the shape of the particle.

virtual void	Init ()
	Initializes the particle by setting default values for all properties.

virtual double	GetDensity () const
	Gets the density of the particle.

virtual void	SetMargin (double m)
	Sets the margin of the particle.

virtual double	GetMargin () const
	Gets the margin of the particle.

virtual void	SetForce (double fx, double fy, double fz)
	Sets the force acting on the particle.

virtual void	SetMoment (double mx, double my, double mz)
	Sets the moment acting on the particle.

virtual void	SetSpin (double spin_x, double spin_y, double spin_z)
	Sets the angular velocity (spin) of the particle.

virtual void	SetDynamicProperty (std::string const &key, double value)
	Set the value of a dynamic property identified by the given key.

virtual double	GetDynamicProperty (std::string const &key)
	Get the value of a dynamic property identified by the given key.

virtual void	AddForce (const Vec3d &force)
	Add a force to the particle.

virtual void	AddMoment (const Vec3d &moment)
	Add a moment (torque) to the particle.

virtual void	AddForceAtomic (const Vec3d &f)
	Add a force to the particle atomically.

virtual void	AddMomentAtomic (const Vec3d &m)
	Add a moment (torque) to the particle atomically.

virtual void	ClearMoment ()
	Clear all moments applied to the particle.

virtual void	UpdateContactForce ()
	Update the contact forces applied to the particle.

void	ClearLinkedCells ()
	Clear the linked cells of the particle.

void	ClearLinkedDomains ()
	Clear the linked domains of the particle.

void	ClearLinkedNeighs ()
	Clear the linked neighbors of the particle.

void	BuildContactRefTable ()
	Build a look-up table for contacts between particles.

void	ClearContactRefTable ()
	Clear the look-up table for contacts between particles.

void	UpdateLinkedDomains (DomainManager *const dm)
	Update the linked domains of the particle based on the given domain manager.

void	UpdateLinkedCells (CellManager *const cm)
	Update the linked cells of the particle based on the given cell manager.

void	UpdateLinkedNeighs (Domain *const domain)
	Update the linked neighbors of the particle based on the given domain.

VecXT< ContactPP * >	GetContactPPs ()
	Get a vector of pointers to all contact points between particles.

VecXT< ContactPW * >	GetContactPWs ()
	Get a vector of pointers to all contact points between particles and walls.

VecXT< std::pair< Domain *, int > > const &	GetLinkedDomains ()
	Gets a vector of pointers to the domains that may be potentially overlapped this wall.

VecXT< std::pair< Cell *, int > > const &	GetLinkedCells ()
	Gets a vector of pointers to the cells that may be potentially overlapped this wall.

VecXT< NeighPofP > const &	GetLinkedParticles ()
	Gets a vector of pointers to the particles that may be potentially overlapped this wall.

VecXT< NeighWofP > const &	GetLinkedWalls ()
	Gets a vector of pointers to the walls that may be potentially overlapped this wall.

NeighPofP *const	GetLinkedParticle (int lookup_id)
	Gets the neigh obj by look-up id.

NeighWofP *const	GetLinkedWall (int lookup_id)
	Gets the neigh obj by look-up id.

virtual void	UpdateSTLModel ()
	Update the geometry of the particle's STL model.

virtual STLModel	GetSTLModel (int num_nodes=200)
	Get a copy of the particle's STL model as an object of type `STLModel`.

virtual STLModel *	GetSTLModelInternal ()
	Get a copy of the particle's STL model as an object of type `STLModel`.

virtual void	Print () const
	Print information about the particle to the console.

virtual	~Particle ()
	Destroy the particle object and free any resources it might be holding.

NeighPofP *	LinkToParticle (Particle *const q)
	Create a new neighbor tuple between this particle and the given particle `q`, and return the newly created tuple.

NeighWofP *	LinkToWall (Wall *const w)
	Create a new neighbor tuple between this particle and the given wall `w`, and return the newly created tuple.

int	LinkToCell (Cell *const cell)
	Create a link between this particle and the given cell and return the look up id.

int	LinkToDomain (Domain *const domain)
	Create a link between this particle and the given domain and return the look up id.

int	FindLinkedParticle (Particle *const q)
	Find the index of the neighbor tuple belonging to this particle that is linked to the given particle `q`.

int	FindLinkedWall (Wall *const w)
	Find the index of the neighbor tuple belonging to this particle that is linked to the given wall `w`.

Public Attributes
TriMesh *	trimesh {nullptr}
	Pointer to the triangular mesh shape of the particle.

TetMesh	tetmesh
	The tetrahedral mesh used for the simulation.

FEMSimulator	fem_simulator
	The FEM simulator object used to simulate the particle.

int	mesh_res {20}
	The resolution of the tetrahedral mesh.

Public Attributes inherited from netdem::Particle
int	id {0}
	The ID of the particle.

Shape *	shape {nullptr}
	The shape of the particle.

Vec3d	bound_min {0, 0, 0}
	The minimum bounds of the particle's shape.

Vec3d	bound_max {0, 0, 0}
	The maximum bounds of the particle's shape.

double	margin {0}
	The margin of the particle's shape.

Vec3d	bound_disp {0, 0, 0}
	The displacement of the particle's bounds for the linked list.

int	material_type {0}
	The material type of the particle.

double	mass {0.0}
	The mass of the particle.

Vec3d	moi_principal {0, 0, 0}
	The principal moment of inertia of the particle.

double	damp_viscous {0}
	The viscous damping coefficient of the particle.

double	damp_numerical {0}
	The numerical damping coefficient of the particle.

Vec3d	pos {0, 0, 0}
	The position of the particle.

Vec4d	quaternion {1, 0, 0, 0}
	The quaternion of the particle.

Vec3d	vel {0, 0, 0}
	The velocity of the particle.

Vec3d	spin {0, 0, 0}
	The spin of the particle.

Vec3d	vel_m0p5 {0, 0, 0}
	The square root velocity of the particle for half-step integration.

Vec3d	spin_principal {0, 0, 0}
	The principal spin axis of the particle.

Vec3d	force {0, 0, 0}
	The force acting on the particle.

Vec3d	moment {0, 0, 0}
	The moment acting on the particle.

MiniMap< std::string, double >	dynamic_properties
	Map of dynamic properties of the particle.

bool	enable_bound_aabb {false}
	Flag indicating whether bounding sphere should be used to approximate axis-aligned bounding box (AABB).

bool	need_update_linked_list {true}
	Flag indicating whether linked-list algorithm should be used for broad-phase contact detection.

bool	need_update_stl_model {false}
	Flag indicating whether STl model intersection-based contact detection and resolution is needed.

Additional Inherited Members
Protected Member Functions inherited from netdem::Particle
void	RemoveLinkedCell (int lookup_id)
	Reomve a linked cell by look-up id.

void	RemoveLinkedDomain (int lookup_id)
	Reomve a linked domain by look-up id.

void	RemoveLinkedParticle (int lookup_id)
	Reomve a linked neighbor by look-up id.

void	RemoveLinkedWall (int lookup_id)
	Reomve a linked neighbor by look-up id.

void	RemoveContactRefPP (int lookup_id)
	Reomve a p-p contact by look-up id.

void	RemoveContactRefPW (int lookup_id)
	Reomve a p-w contact by look-up id.

NeighPofP *const	GetLinkedContactRefPP (int lookup_id)
	Gets the neigh obj by look-up id.

NeighWofP *const	GetLinkedContactRefPW (int lookup_id)
	Gets the neigh obj by look-up id.

NeighPofP *	BuildContactRefPP (Particle const q, ContactPP const cnt)
	Create a new contact lookup table entry for the given pair of particles `q` and `cnt`, and return the newly created entry.

NeighWofP *	BuildContactRefPW (Wall const w, ContactPW const cnt)
	Create a new contact lookup table entry for the given wall `w` and contact point `cnt`, and return the newly created entry.

int	FindContactRefPP (Particle *const q)
	Find the index of the contact lookup table entry belonging to this particle that references the given particle `q`.

int	FindContactRefPW (Wall *const w)
	Find the index of the contact lookup table entry belonging to this particle that references the given wall `w`.

Protected Attributes inherited from netdem::Particle
double	density {2650}
	The density of the particle. Please use SetDensity to change its value.

VecXT< std::pair< Cell *, int > >	linked_cell_list
	List of linked cells used for broad-phase contact detection.

VecXT< NeighPofP >	linked_particle_list
	List of linked particles used for narrow-phase contact detection with particles.

VecXT< NeighWofP >	linked_wall_list
	List of linked walls used for narrow-phase contact detection with walls.

VecXT< NeighPofP >	contact_pp_ref_table
	Lookup table used to reconstruct reference of contact history with particles.

VecXT< NeighWofP >	contact_pw_ref_table
	Lookup table used to reconstruct reference of contact history with walls.

bool	is_on_edge {false}
	Flag indicating whether particle is on domain edge.

bool	need_send_out {false}
	Flag indicating whether data needs to be sent out to linked domains.

VecXT< std::pair< Domain *, int > >	linked_domain_list
	List of linked domains that overlap with the particle.

STLModel	stl_model
	STLModel object used for intersection-based contact detection and resolution.

Detailed Description

A class representing a deformable particle simulated using the Finite Element Method (FEM).

This class inherits from the Particle class and includes additional functionality for simulating deformable particles using FEM. It contains a triangular mesh shape and a tetrahedral mesh used for the simulation, as well as functions to update the motion and shape of the particle, apply contact forces, and save data in VTK format.

Examples: 00_hertz_contact.cpp, and 81_golf_ball_impact.cpp.

Constructor & Destructor Documentation

◆ DeformableParticle()

netdem::DeformableParticle::DeformableParticle ( )

Constructs a new DeformableParticle object.

◆ ~DeformableParticle()

netdem::DeformableParticle::~DeformableParticle ( )

override

Destroys the DeformableParticle object and frees any memory used by it.

Member Function Documentation

◆ AddForce()

void netdem::DeformableParticle::AddForce	(	int	node_id,
		Vec3d const &	f )

Adds a force to a node on the particle's mesh.

This function adds a force to a specific node on the particle's tetrahedral mesh.

Parameters

node_id	The ID of the node to add the force to.
f	The force vector to add to the node.

Examples: 00_hertz_contact.cpp.

◆ ApplyContactForce() [1/2]

void netdem::DeformableParticle::ApplyContactForce ( ContactPP const * cnt )

overridevirtual

Applies a contact force to the particle.

This function applies a contact force between two particles using a point-particle contact model. It overrides the ApplyContactForce method from the Particle class.

Parameters

cnt	A pointer to the `ContactPP` object representing the contact.

Reimplemented from netdem::Particle.

Examples: 81_golf_ball_impact.cpp.

◆ ApplyContactForce() [2/2]

void netdem::DeformableParticle::ApplyContactForce ( ContactPW const * cnt )

overridevirtual

Applies a contact force between a particle and a wall.

This function applies a contact force between a particle and a wall using a point-wall contact model. It overrides the ApplyContactForce method from the Particle class.

Parameters

cnt	A pointer to the `ContactPW` object representing the contact.

Reimplemented from netdem::Particle.

◆ ClearForce()

void netdem::DeformableParticle::ClearForce ( )

overridevirtual

Clears all forces on the particle's mesh.

This function clears all forces applied to the nodes on this particle's tetrahedral mesh. It overrides the ClearForce method from the Particle class.

Reimplemented from netdem::Particle.

Examples: 00_hertz_contact.cpp, and 81_golf_ball_impact.cpp.

◆ Clone()

Particle * netdem::DeformableParticle::Clone ( ) const

overridevirtual

Creates a new instance of this object.

This function returns a new DeformableParticle object that is a copy of the current object. It overrides the Clone method from the Particle class.

Returns: A pointer to the new DeformableParticle object.

Reimplemented from netdem::Particle.

◆ GetVelocity()

Vec3d netdem::DeformableParticle::GetVelocity ( Vec3d const & pos )

overridevirtual

Gets the velocity of the particle at a given position.

This function returns the velocity of the particle at a given position in space. It overrides the GetVelocity method from the Particle class.

Parameters

pos	The position vector to get the velocity at.

Returns: The velocity vector at the specified position.

Reimplemented from netdem::Particle.

◆ InitFEMMesh()

void netdem::DeformableParticle::InitFEMMesh ( )

Initialized the mesh for FEM analysis.

◆ SaveAsVTK()

void netdem::DeformableParticle::SaveAsVTK ( std::string const & filename )

overridevirtual

Saves the particle as a VTK file.

This function saves the particle, including its tetrahedral mesh, to a VTK file. It overrides the SaveAsVTK method from the Particle class.

Parameters

filename The name of the file to save the data in.

Reimplemented from netdem::Particle.

Examples: 00_hertz_contact.cpp, and 81_golf_ball_impact.cpp.

◆ SaveSurfaceAsVTK()

void netdem::DeformableParticle::SaveSurfaceAsVTK ( std::string const & filename )

Saves the surface of the particle as a VTK file.

This function saves the surface of the particle's triangular mesh shape to a VTK file.

Parameters

filename The name of the file to save the data in.

Examples: 81_golf_ball_impact.cpp.

◆ SetDensity()

void netdem::DeformableParticle::SetDensity ( double dens )

overridevirtual

Sets the density of the particle.

This function sets the density of the particle and updates its mass accordingly. It overrides the SetDensity method from the Particle class.

Parameters

dens	The density value to set.

Reimplemented from netdem::Particle.

Examples: 81_golf_ball_impact.cpp.

◆ SetPosition()

void netdem::DeformableParticle::SetPosition	(	double	x,
		double	y,
		double	z )

overridevirtual

Sets the position of the particle.

This function sets the position of the particle to a given point in 3D space. It overrides the SetPosition method from the Particle class.

Parameters

x	The X coordinate of the new position.
y	The Y coordinate of the new position.
z	The Z coordinate of the new position.

Reimplemented from netdem::Particle.

Examples: 81_golf_ball_impact.cpp.

◆ SetQuaternion()

void netdem::DeformableParticle::SetQuaternion	(	double	q_0,
		double	q_1,
		double	q_2,
		double	q_3 )

overridevirtual

Sets the orientation of the particle using a quaternion.

This function sets the orientation of the particle using a quaternion representation. It overrides the SetQuaternion method from the Particle class.

Parameters

q_0	The scalar component of the quaternion.
q_1	The X-component of the quaternion.
q_2	The Y-component of the quaternion.
q_3	The Z-component of the quaternion.

Reimplemented from netdem::Particle.

◆ SetRodrigues()

void netdem::DeformableParticle::SetRodrigues	(	double	angle,
		double	axis_x,
		double	axis_y,
		double	axis_z )

overridevirtual

Sets the angle and axis of rotation for the particle.

This function sets the angle and axis of rotation for the particle using Rodrigues' formula. It overrides the SetRodrigues method from the Particle class.

Parameters

angle	The angle of rotation in radians.
axis_x	The X component of the rotation axis.
axis_y	The Y component of the rotation axis.
axis_z	The Z component of the rotation axis.

Reimplemented from netdem::Particle.

◆ SetShape()

void netdem::DeformableParticle::SetShape ( Shape * s )

overridevirtual

Sets the shape of the particle.

This function sets the shape of the particle to a given Shape object by generating a tetrahedral mesh from the object's triangular mesh. It overrides the SetShape method from the Particle class.

Parameters

s	A pointer to the `Shape` object to use for setting the particle's shape.

Reimplemented from netdem::Particle.

Examples: 00_hertz_contact.cpp, and 81_golf_ball_impact.cpp.

◆ SetVelocity()

void netdem::DeformableParticle::SetVelocity	(	double	v_x,
		double	v_y,
		double	v_z )

overridevirtual

Sets the velocity of the particle.

This function sets the velocity of the particle to a given vector in 3D space. It overrides the SetVelocity method from the Particle class.

Parameters

v_x	The X component of the new velocity vector.
v_y	The Y component of the new velocity vector.
v_z	The Z component of the new velocity vector.

Reimplemented from netdem::Particle.

Examples: 81_golf_ball_impact.cpp.

◆ UpdateBound()

void netdem::DeformableParticle::UpdateBound ( )

overridevirtual

Updates the bounding box of the particle.

This function updates the bounding box of the particle's tetrahedral mesh based on its current configuration. It overrides the UpdateBound method from the Particle class.

Reimplemented from netdem::Particle.

◆ UpdateBoundFast()

void netdem::DeformableParticle::UpdateBoundFast ( )

overridevirtual

Updates the bounding box of the particle.

This function updates the bounding box of the particle's tetrahedral mesh based on its current configuration. It overrides the UpdateBound method from the Particle class.

Reimplemented from netdem::Particle.

◆ UpdateMotion()

void netdem::DeformableParticle::UpdateMotion ( double dt )

overridevirtual

Updates the motion of the particle.

This function updates the motion of the particle using the FEM simulator object. It overrides the UpdateMotion method from the Particle class.

Parameters

dt	The time step to use for the update.

Reimplemented from netdem::Particle.

Examples: 00_hertz_contact.cpp, and 81_golf_ball_impact.cpp.

◆ UpdateShape()

void netdem::DeformableParticle::UpdateShape ( )

Updates the shape of the particle.

This function updates the shape of the particle's tetrahedral mesh based on the current state of the triangular mesh shape. It is called automatically by UpdateMotion.

Member Data Documentation

◆ fem_simulator

FEMSimulator netdem::DeformableParticle::fem_simulator

The FEM simulator object used to simulate the particle.

Examples: 00_hertz_contact.cpp, and 81_golf_ball_impact.cpp.

◆ mesh_res

int netdem::DeformableParticle::mesh_res {20}

The resolution of the tetrahedral mesh.

Examples: 81_golf_ball_impact.cpp.

◆ tetmesh

TetMesh netdem::DeformableParticle::tetmesh

The tetrahedral mesh used for the simulation.

◆ trimesh

TriMesh* netdem::DeformableParticle::trimesh {nullptr}

Pointer to the triangular mesh shape of the particle.

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

/Users/lzhshou/Documents/Research/myProjects/apaam/repo/netdem/src/fem/deformable_particle.hpp
/Users/lzhshou/Documents/Research/myProjects/apaam/repo/netdem/src/fem/deformable_particle.cpp

Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ DeformableParticle()

◆ ~DeformableParticle()

Member Function Documentation

◆ AddForce()

◆ ApplyContactForce() [1/2]

◆ ApplyContactForce() [2/2]

◆ ClearForce()

◆ Clone()

◆ GetVelocity()

◆ InitFEMMesh()

◆ SaveAsVTK()

◆ SaveSurfaceAsVTK()

◆ SetDensity()

◆ SetPosition()

◆ SetQuaternion()

◆ SetRodrigues()

◆ SetShape()

◆ SetVelocity()

◆ UpdateBound()

◆ UpdateBoundFast()

◆ UpdateMotion()

◆ UpdateShape()

Member Data Documentation

◆ fem_simulator

◆ mesh_res

◆ tetmesh

◆ trimesh