chrono::fea::ChContactSurfaceMesh Class Reference

Description

Class which defines a contact surface for FEA elements, using a mesh of triangles.

Differently from ChContactSurfaceNodeCloud, this also captures the node-vs-face and edge-vs-edge cases, but has a higher computational overhead.

#include <ChContactSurfaceMesh.h>

Inheritance diagram for chrono::fea::ChContactSurfaceMesh:

Collaboration diagram for chrono::fea::ChContactSurfaceMesh:

Public Member Functions
	ChContactSurfaceMesh (std::shared_ptr< ChContactMaterial > material, ChMesh *mesh=nullptr)
void	AddFacesFromBoundary (const ChMesh &mesh, double sphere_swept=0.0, bool ccw=true, bool include_cable_elements=true, bool include_beam_elements=true)
	Utility function to add all boundary faces of the specified FEA mesh to this collision surface. More...
void	ConstructFromTrimesh (std::shared_ptr< ChTriangleMeshConnected > trimesh, double sphere_swept=0.0)
	Construct a contact surface from a triangular mesh. More...
virtual ChAABB	GetAABB () const override
	Get the current axis-aligned bounding box.
std::vector< std::shared_ptr< ChContactTriangleXYZ > > &	GetTrianglesXYZ ()
	Get the list of triangles.
std::vector< std::shared_ptr< ChContactTriangleXYZRot > > &	GetTrianglesXYZRot ()
	Get the list of triangles for nodes with rotational dofs.
unsigned int	GetNumTriangles () const
	Get the number of triangles.
unsigned int	GetNumVertices () const
	Get the number of vertices.
virtual void	SyncCollisionModels () const override
virtual void	AddCollisionModelsToSystem (ChCollisionSystem *coll_sys) const override
virtual void	RemoveCollisionModelsFromSystem (ChCollisionSystem *coll_sys) const override
void	OutputSimpleMesh (std::vector< ChVector3d > &vert_pos, std::vector< ChVector3d > &vert_vel, std::vector< ChVector3i > &triangles, std::vector< ChVector3b > &owns_node, std::vector< ChVector3b > &owns_edge) const
	Utility function for exporting the contact mesh in a pointer-less manner. More...
Public Member Functions inherited from chrono::fea::ChContactSurface
	ChContactSurface (std::shared_ptr< ChContactMaterial > material, ChPhysicsItem *mesh=nullptr)
ChPhysicsItem *	GetPhysicsItem ()
	Get the owner physics item (e.g., an FEA mesh).
void	SetPhysicsItem (ChPhysicsItem *physics_item)
	Set the owner physics item (e.g., an FEA mesh).
void	DisableSelfCollisions (int family)
	Disable self-collisions (default: enabled). More...
std::shared_ptr< ChContactMaterial > &	GetMaterialSurface ()
	Get the surface contact material.

Additional Inherited Members
Protected Attributes inherited from chrono::fea::ChContactSurface
std::shared_ptr< ChContactMaterial >	m_material
	contact material properties
ChPhysicsItem *	m_physics_item
	associated physics item (e.g., an FEA mesh)
bool	m_self_collide
	include self-collisions?
int	m_collision_family
	collision family (if no self-collisions)

Member Function Documentation

AddFacesFromBoundary()

void chrono::fea::ChContactSurfaceMesh::AddFacesFromBoundary	(	const ChMesh &	mesh,
		double	sphere_swept = 0.0,
		bool	ccw = true,
		bool	include_cable_elements = true,
		bool	include_beam_elements = true
	)

Utility function to add all boundary faces of the specified FEA mesh to this collision surface.

The function scans all the finite elements already added in the parent ChMesh and adds the faces that are not shared (ie. the faces on the boundary 'skin'). For shells, the argument 'ccw' indicates whether the face vertices are provided in a counter-clockwise (default) or clockwise order(because shells collisions are oriented and might work only from the "outer" side). Currently supported elements that generate boundary skin:

• solids:
  • ChElementTetrahedron: all solid tetrahedrons
  • ChElementHexahedron: all solid hexahedrons
• shells:
  • ChElementShellANCF_3423 ANCF: shells (only one side)
  • ChElementShellANCF_3443 ANCF: shells (only one side)
  • ChElementShellANCF_3833 ANCF: shells (only one side)
  • ChElementShellReissner: Reissner 4-nodes shells (only one side)
• beams:
  • ChElementCableANCF: ANCF beams (as sphere-swept lines, i.e. sequence of capsules)
  • ChElementBeamEuler: Euler-Bernoulli beams (as sphere-swept lines, i.e. sequence of capsules)

Parameters

mesh	FEA mesh
sphere_swept	radius of swept sphere
ccw	indicate counterclockwise vertex ordering
include_cable_elements	create contact triangles for cable elements
include_beam_elements	create contact triangles for beam elements

ConstructFromTrimesh()

void chrono::fea::ChContactSurfaceMesh::ConstructFromTrimesh	(	std::shared_ptr< ChTriangleMeshConnected >	trimesh,
		double	sphere_swept = 0.0
	)

Construct a contact surface from a triangular mesh.

FEA nodes are created at the mesh vertex locations.

OutputSimpleMesh()

void chrono::fea::ChContactSurfaceMesh::OutputSimpleMesh	(	std::vector< ChVector3d > &	vert_pos,
		std::vector< ChVector3d > &	vert_vel,
		std::vector< ChVector3i > &	triangles,
		std::vector< ChVector3b > &	owns_node,
		std::vector< ChVector3b > &	owns_edge
	)		const

Utility function for exporting the contact mesh in a pointer-less manner.

The mesh is specified as a set of 3D vertex points (with associated velocities) and a set of faces (indices into the vertex array). In addition, ownership of nodes and edges among the consitutent triangles is returned in 'owns_node' and 'owns_edge'.

Parameters

vert_pos	mesh vertices (absolute xyz positions)
vert_vel	vertex velocities (absolute xyz velocities)
triangles	triangle faces (indices in vertex array)
owns_node	node ownership for each triangular face
owns_edge	edge ownership for each triangular face

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

• /builds/uwsbel/chrono/src/chrono/fea/ChContactSurfaceMesh.h
• /builds/uwsbel/chrono/src/chrono/fea/ChContactSurfaceMesh.cpp