Tangential Collisions

class ipctk.TangentialCollisions

Bases: pybind11_object

Public Methods:

__init__(self)

build(*args, **kwargs)

Overloaded function.

__len__(self)

Get the number of friction collisions.

empty(self)

Get if the friction collisions are empty.

clear(self)

Clear the friction collisions.

__getitem__(self, i)

Get a reference to collision at index i.

default_blend_mu(mu0, mu1)

Inherited from pybind11_object

__annotations__ = {}
__getitem__(self, i: int) ipctk.TangentialCollision

Get a reference to collision at index i.

Parameters:
i: int

The index of the collision.

Returns:

A reference to the collision.

__init__(self)
__len__(self) int

Get the number of friction collisions.

__module__ = 'ipctk'
build(*args, **kwargs)

Overloaded function.

  1. build(self: ipctk.TangentialCollisions, mesh: ipc::CollisionMesh, vertices: numpy.ndarray[numpy.float64[m, n]], collisions: ipctk.NormalCollisions, normal_potential: ipc::NormalPotential, normal_stiffness: float, mu: float) -> None

  2. build(self: ipctk.TangentialCollisions, mesh: ipc::CollisionMesh, vertices: numpy.ndarray[numpy.float64[m, n]], collisions: ipctk.NormalCollisions, normal_potential: ipc::NormalPotential, normal_stiffness: float, mus: numpy.ndarray[numpy.float64[m, 1]]) -> None

  3. build(self: ipctk.TangentialCollisions, mesh: ipc::CollisionMesh, vertices: numpy.ndarray[numpy.float64[m, n]], collisions: ipctk.NormalCollisions, normal_potential: ipc::NormalPotential, normal_stiffness: float, mus: numpy.ndarray[numpy.float64[m, 1]], blend_mu: Callable[[float, float], float]) -> None

clear(self) None

Clear the friction collisions.

static default_blend_mu(mu0: float, mu1: float) float
property ee_collisions : list[ipc::EdgeEdgeTangentialCollision]
empty(self) bool

Get if the friction collisions are empty.

property ev_collisions : list[ipc::EdgeVertexTangentialCollision]
property fv_collisions : list[ipc::FaceVertexTangentialCollision]
property vv_collisions : list[ipc::VertexVertexTangentialCollision]

Tangential Collision

class ipctk.TangentialCollision

Bases: CollisionStencil

Public Data Attributes:

dim

Get the dimension of the collision.

ndof

Get the number of degrees of freedom for the collision.

normal_force_magnitude

Normal force magnitude

mu

Ratio between normal and tangential forces (e.g., friction coefficient)

weight

Weight

weight_gradient

Gradient of weight with respect to all DOF

closest_point

Barycentric coordinates of the closest point(s)

tangent_basis

Tangent basis of the collision (max size 3×2)

Public Methods:

__init__(*args, **kwargs)

compute_tangent_basis(self, positions)

Compute the tangent basis of the collision.

compute_tangent_basis_jacobian(self, positions)

Compute the Jacobian of the tangent basis of the collision.

compute_closest_point(self, positions)

Compute the barycentric coordinates of the closest point.

compute_closest_point_jacobian(self, positions)

Compute the Jacobian of the barycentric coordinates of the closest point.

relative_velocity(self, velocities)

Compute the relative velocity of the collision.

relative_velocity_matrix(*args, **kwargs)

Overloaded function.

relative_velocity_matrix_jacobian(self, ...)

Construct the Jacobian of the relative velocity premultiplier wrt the closest points.

Inherited from CollisionStencil

__init__(*args, **kwargs)

num_vertices(self)

Get the number of vertices in the collision stencil.

dim(self, ndof)

Get the dimension of the collision stencil.

vertex_ids(self, edges, faces)

Get the vertex IDs of the collision stencil.

vertices(self, vertices, edges, faces)

Get the vertex attributes of the collision stencil.

dof(self, X, edges, faces)

Select this stencil's DOF from the full matrix of DOF.

compute_distance(self, positions)

Compute the distance of the stencil.

compute_distance_gradient(self, positions)

Compute the distance gradient of the stencil w.r.t.

compute_distance_hessian(self, positions)

Compute the distance Hessian of the stencil w.r.t.

Inherited from pybind11_object

__annotations__ = {}
__init__(*args, **kwargs)
__module__ = 'ipctk'
property closest_point : numpy.ndarray[numpy.float64[m, 1]]

Barycentric coordinates of the closest point(s)

compute_closest_point(self, positions: numpy.ndarray[numpy.float64[m, 1]]) numpy.ndarray[numpy.float64[m, 1]]

Compute the barycentric coordinates of the closest point.

Parameters:
positions: numpy.ndarray[numpy.float64[m, 1]]

Collision stencil’s vertex positions.

Returns:

Barycentric coordinates of the closest point.

compute_closest_point_jacobian(self, positions: numpy.ndarray[numpy.float64[m, 1]]) numpy.ndarray[numpy.float64[m, n]]

Compute the Jacobian of the barycentric coordinates of the closest point.

Parameters:
positions: numpy.ndarray[numpy.float64[m, 1]]

Collision stencil’s vertex positions.

Returns:

Jacobian of the barycentric coordinates of the closest point.

compute_tangent_basis(self, positions: numpy.ndarray[numpy.float64[m, 1]]) numpy.ndarray[numpy.float64[m, n]]

Compute the tangent basis of the collision.

Parameters:
positions: numpy.ndarray[numpy.float64[m, 1]]

Collision stencil’s vertex positions.

Returns:

Tangent basis of the collision.

compute_tangent_basis_jacobian(self, positions: numpy.ndarray[numpy.float64[m, 1]]) numpy.ndarray[numpy.float64[m, n]]

Compute the Jacobian of the tangent basis of the collision.

Parameters:
positions: numpy.ndarray[numpy.float64[m, 1]]

Collision stencil’s vertex positions.

Returns:

Jacobian of the tangent basis of the collision.

property dim : int

Get the dimension of the collision.

property mu : float

Ratio between normal and tangential forces (e.g., friction coefficient)

property ndof : int

Get the number of degrees of freedom for the collision.

property normal_force_magnitude : float

Normal force magnitude

relative_velocity(self, velocities: numpy.ndarray[numpy.float64[m, 1]]) numpy.ndarray[numpy.float64[m, 1]]

Compute the relative velocity of the collision.

Parameters:
velocities: numpy.ndarray[numpy.float64[m, 1]]

Collision stencil’s vertex velocities.

Returns:

Relative velocity of the collision.

relative_velocity_matrix(*args, **kwargs)

Overloaded function.

  1. relative_velocity_matrix(self: ipctk.TangentialCollision) -> numpy.ndarray[numpy.float64[m, n]]

    Construct the premultiplier matrix for the relative velocity.

    Note:

    Uses the cached closest point.

    Returns:

    A matrix M such that relative_velocity = M * velocities.

  2. relative_velocity_matrix(self: ipctk.TangentialCollision, closest_point: numpy.ndarray[numpy.float64[m, 1]]) -> numpy.ndarray[numpy.float64[m, n]]

    Construct the premultiplier matrix for the relative velocity.

    Parameters:

    closest_point: Barycentric coordinates of the closest point.

    Returns:

    A matrix M such that relative_velocity = M * velocities.

relative_velocity_matrix_jacobian(self, closest_point: numpy.ndarray[numpy.float64[m, 1]]) numpy.ndarray[numpy.float64[m, n]]

Construct the Jacobian of the relative velocity premultiplier wrt the closest points.

Parameters:
closest_point: numpy.ndarray[numpy.float64[m, 1]]

Barycentric coordinates of the closest point.

Returns:

Jacobian of the relative velocity premultiplier wrt the closest points.

property tangent_basis : numpy.ndarray[numpy.float64[m, n]]

Tangent basis of the collision (max size 3×2)

property weight : float

Weight

property weight_gradient : scipy.sparse.csc_matrix[numpy.float64]

Gradient of weight with respect to all DOF

Vertex-Vertex Tangential Collision

class ipctk.VertexVertexTangentialCollision

Bases: VertexVertexCandidate, TangentialCollision

Public Data Attributes:

Inherited from VertexVertexCandidate

vertex0_id

ID of the first vertex

vertex1_id

ID of the second vertex

Inherited from TangentialCollision

dim

Get the dimension of the collision.

ndof

Get the number of degrees of freedom for the collision.

normal_force_magnitude

Normal force magnitude

mu

Ratio between normal and tangential forces (e.g., friction coefficient)

weight

Weight

weight_gradient

Gradient of weight with respect to all DOF

closest_point

Barycentric coordinates of the closest point(s)

tangent_basis

Tangent basis of the collision (max size 3×2)

Public Methods:

__init__(*args, **kwargs)

Overloaded function.

Inherited from VertexVertexCandidate

__init__(self, vertex0_id, vertex1_id)

__str__(self)

__repr__(self)

__eq__(self, other)

__ne__(self, other)

__lt__(self, other)

Compare EdgeVertexCandidates for sorting.

Inherited from TangentialCollision

__init__(*args, **kwargs)

compute_tangent_basis(self, positions)

Compute the tangent basis of the collision.

compute_tangent_basis_jacobian(self, positions)

Compute the Jacobian of the tangent basis of the collision.

compute_closest_point(self, positions)

Compute the barycentric coordinates of the closest point.

compute_closest_point_jacobian(self, positions)

Compute the Jacobian of the barycentric coordinates of the closest point.

relative_velocity(self, velocities)

Compute the relative velocity of the collision.

relative_velocity_matrix(*args, **kwargs)

Overloaded function.

relative_velocity_matrix_jacobian(self, ...)

Construct the Jacobian of the relative velocity premultiplier wrt the closest points.

Inherited from CollisionStencil

__init__(*args, **kwargs)

num_vertices(self)

Get the number of vertices in the collision stencil.

dim(self, ndof)

Get the dimension of the collision stencil.

vertex_ids(self, edges, faces)

Get the vertex IDs of the collision stencil.

vertices(self, vertices, edges, faces)

Get the vertex attributes of the collision stencil.

dof(self, X, edges, faces)

Select this stencil's DOF from the full matrix of DOF.

compute_distance(self, positions)

Compute the distance of the stencil.

compute_distance_gradient(self, positions)

Compute the distance gradient of the stencil w.r.t.

compute_distance_hessian(self, positions)

Compute the distance Hessian of the stencil w.r.t.

Inherited from ContinuousCollisionCandidate

__init__(*args, **kwargs)

ccd(self, vertices_t0, 1]], vertices_t1, ...)

Perform narrow-phase CCD on the candidate.

print_ccd_query(self, vertices_t0, vertices_t1)

Print the CCD query to cout.

Inherited from pybind11_object

__annotations__ = {}
__init__(*args, **kwargs)

Overloaded function.

  1. __init__(self: ipctk.VertexVertexTangentialCollision, collision: ipctk.VertexVertexNormalCollision) -> None

  2. __init__(self: ipctk.VertexVertexTangentialCollision, collision: ipctk.VertexVertexNormalCollision, positions: numpy.ndarray[numpy.float64[m, 1]], normal_potential: ipc::NormalPotential, normal_stiffness: float) -> None

__module__ = 'ipctk'

Edge-Vertex Tangential Collision

class ipctk.EdgeVertexTangentialCollision

Bases: EdgeVertexCandidate, TangentialCollision

Public Data Attributes:

Inherited from EdgeVertexCandidate

edge_id

ID of the edge

vertex_id

ID of the vertex

Inherited from TangentialCollision

dim

Get the dimension of the collision.

ndof

Get the number of degrees of freedom for the collision.

normal_force_magnitude

Normal force magnitude

mu

Ratio between normal and tangential forces (e.g., friction coefficient)

weight

Weight

weight_gradient

Gradient of weight with respect to all DOF

closest_point

Barycentric coordinates of the closest point(s)

tangent_basis

Tangent basis of the collision (max size 3×2)

Public Methods:

__init__(*args, **kwargs)

Overloaded function.

Inherited from EdgeVertexCandidate

__init__(self, edge_id, vertex_id)

known_dtype(self)

__str__(self)

__repr__(self)

__eq__(self, other)

__ne__(self, other)

__lt__(self, other)

Compare EdgeVertexCandidates for sorting.

Inherited from TangentialCollision

__init__(*args, **kwargs)

compute_tangent_basis(self, positions)

Compute the tangent basis of the collision.

compute_tangent_basis_jacobian(self, positions)

Compute the Jacobian of the tangent basis of the collision.

compute_closest_point(self, positions)

Compute the barycentric coordinates of the closest point.

compute_closest_point_jacobian(self, positions)

Compute the Jacobian of the barycentric coordinates of the closest point.

relative_velocity(self, velocities)

Compute the relative velocity of the collision.

relative_velocity_matrix(*args, **kwargs)

Overloaded function.

relative_velocity_matrix_jacobian(self, ...)

Construct the Jacobian of the relative velocity premultiplier wrt the closest points.

Inherited from CollisionStencil

__init__(*args, **kwargs)

num_vertices(self)

Get the number of vertices in the collision stencil.

dim(self, ndof)

Get the dimension of the collision stencil.

vertex_ids(self, edges, faces)

Get the vertex IDs of the collision stencil.

vertices(self, vertices, edges, faces)

Get the vertex attributes of the collision stencil.

dof(self, X, edges, faces)

Select this stencil's DOF from the full matrix of DOF.

compute_distance(self, positions)

Compute the distance of the stencil.

compute_distance_gradient(self, positions)

Compute the distance gradient of the stencil w.r.t.

compute_distance_hessian(self, positions)

Compute the distance Hessian of the stencil w.r.t.

Inherited from ContinuousCollisionCandidate

__init__(*args, **kwargs)

ccd(self, vertices_t0, 1]], vertices_t1, ...)

Perform narrow-phase CCD on the candidate.

print_ccd_query(self, vertices_t0, vertices_t1)

Print the CCD query to cout.

Inherited from pybind11_object

__annotations__ = {}
__init__(*args, **kwargs)

Overloaded function.

  1. __init__(self: ipctk.EdgeVertexTangentialCollision, collision: ipctk.EdgeVertexNormalCollision) -> None

  2. __init__(self: ipctk.EdgeVertexTangentialCollision, collision: ipctk.EdgeVertexNormalCollision, positions: numpy.ndarray[numpy.float64[m, 1]], normal_potential: ipc::NormalPotential, normal_stiffness: float) -> None

__module__ = 'ipctk'

Edge-Edge Tangential Collision

class ipctk.EdgeEdgeTangentialCollision

Bases: EdgeEdgeCandidate, TangentialCollision

Public Data Attributes:

Inherited from EdgeEdgeCandidate

edge0_id

ID of the first edge.

edge1_id

ID of the second edge.

Inherited from TangentialCollision

dim

Get the dimension of the collision.

ndof

Get the number of degrees of freedom for the collision.

normal_force_magnitude

Normal force magnitude

mu

Ratio between normal and tangential forces (e.g., friction coefficient)

weight

Weight

weight_gradient

Gradient of weight with respect to all DOF

closest_point

Barycentric coordinates of the closest point(s)

tangent_basis

Tangent basis of the collision (max size 3×2)

Public Methods:

__init__(*args, **kwargs)

Overloaded function.

Inherited from EdgeEdgeCandidate

__init__(self, edge0_id, edge1_id)

known_dtype(self)

__str__(self)

__repr__(self)

__eq__(self, other)

__ne__(self, other)

__lt__(self, other)

Compare EdgeEdgeCandidates for sorting.

Inherited from TangentialCollision

__init__(*args, **kwargs)

compute_tangent_basis(self, positions)

Compute the tangent basis of the collision.

compute_tangent_basis_jacobian(self, positions)

Compute the Jacobian of the tangent basis of the collision.

compute_closest_point(self, positions)

Compute the barycentric coordinates of the closest point.

compute_closest_point_jacobian(self, positions)

Compute the Jacobian of the barycentric coordinates of the closest point.

relative_velocity(self, velocities)

Compute the relative velocity of the collision.

relative_velocity_matrix(*args, **kwargs)

Overloaded function.

relative_velocity_matrix_jacobian(self, ...)

Construct the Jacobian of the relative velocity premultiplier wrt the closest points.

Inherited from CollisionStencil

__init__(*args, **kwargs)

num_vertices(self)

Get the number of vertices in the collision stencil.

dim(self, ndof)

Get the dimension of the collision stencil.

vertex_ids(self, edges, faces)

Get the vertex IDs of the collision stencil.

vertices(self, vertices, edges, faces)

Get the vertex attributes of the collision stencil.

dof(self, X, edges, faces)

Select this stencil's DOF from the full matrix of DOF.

compute_distance(self, positions)

Compute the distance of the stencil.

compute_distance_gradient(self, positions)

Compute the distance gradient of the stencil w.r.t.

compute_distance_hessian(self, positions)

Compute the distance Hessian of the stencil w.r.t.

Inherited from ContinuousCollisionCandidate

__init__(*args, **kwargs)

ccd(self, vertices_t0, 1]], vertices_t1, ...)

Perform narrow-phase CCD on the candidate.

print_ccd_query(self, vertices_t0, vertices_t1)

Print the CCD query to cout.

Inherited from pybind11_object

__annotations__ = {}
__init__(*args, **kwargs)

Overloaded function.

  1. __init__(self: ipctk.EdgeEdgeTangentialCollision, collision: ipctk.EdgeEdgeNormalCollision) -> None

  2. __init__(self: ipctk.EdgeEdgeTangentialCollision, collision: ipctk.EdgeEdgeNormalCollision, positions: numpy.ndarray[numpy.float64[m, 1]], normal_potential: ipc::NormalPotential, normal_stiffness: float) -> None

__module__ = 'ipctk'

Face-Vertex Tangential Collision

class ipctk.FaceVertexTangentialCollision

Bases: FaceVertexCandidate, TangentialCollision

Public Data Attributes:

Inherited from FaceVertexCandidate

face_id

ID of the face

vertex_id

ID of the vertex

Inherited from TangentialCollision

dim

Get the dimension of the collision.

ndof

Get the number of degrees of freedom for the collision.

normal_force_magnitude

Normal force magnitude

mu

Ratio between normal and tangential forces (e.g., friction coefficient)

weight

Weight

weight_gradient

Gradient of weight with respect to all DOF

closest_point

Barycentric coordinates of the closest point(s)

tangent_basis

Tangent basis of the collision (max size 3×2)

Public Methods:

__init__(*args, **kwargs)

Overloaded function.

Inherited from FaceVertexCandidate

__init__(self, face_id, vertex_id)

known_dtype(self)

__str__(self)

__repr__(self)

__eq__(self, other)

__ne__(self, other)

__lt__(self, other)

Compare FaceVertexCandidate for sorting.

Inherited from TangentialCollision

__init__(*args, **kwargs)

compute_tangent_basis(self, positions)

Compute the tangent basis of the collision.

compute_tangent_basis_jacobian(self, positions)

Compute the Jacobian of the tangent basis of the collision.

compute_closest_point(self, positions)

Compute the barycentric coordinates of the closest point.

compute_closest_point_jacobian(self, positions)

Compute the Jacobian of the barycentric coordinates of the closest point.

relative_velocity(self, velocities)

Compute the relative velocity of the collision.

relative_velocity_matrix(*args, **kwargs)

Overloaded function.

relative_velocity_matrix_jacobian(self, ...)

Construct the Jacobian of the relative velocity premultiplier wrt the closest points.

Inherited from CollisionStencil

__init__(*args, **kwargs)

num_vertices(self)

Get the number of vertices in the collision stencil.

dim(self, ndof)

Get the dimension of the collision stencil.

vertex_ids(self, edges, faces)

Get the vertex IDs of the collision stencil.

vertices(self, vertices, edges, faces)

Get the vertex attributes of the collision stencil.

dof(self, X, edges, faces)

Select this stencil's DOF from the full matrix of DOF.

compute_distance(self, positions)

Compute the distance of the stencil.

compute_distance_gradient(self, positions)

Compute the distance gradient of the stencil w.r.t.

compute_distance_hessian(self, positions)

Compute the distance Hessian of the stencil w.r.t.

Inherited from ContinuousCollisionCandidate

__init__(*args, **kwargs)

ccd(self, vertices_t0, 1]], vertices_t1, ...)

Perform narrow-phase CCD on the candidate.

print_ccd_query(self, vertices_t0, vertices_t1)

Print the CCD query to cout.

Inherited from pybind11_object

__annotations__ = {}
__init__(*args, **kwargs)

Overloaded function.

  1. __init__(self: ipctk.FaceVertexTangentialCollision, collision: ipctk.FaceVertexNormalCollision) -> None

  2. __init__(self: ipctk.FaceVertexTangentialCollision, collision: ipctk.FaceVertexNormalCollision, positions: numpy.ndarray[numpy.float64[m, 1]], normal_potential: ipc::NormalPotential, normal_stiffness: float) -> None

__module__ = 'ipctk'

Last update: Dec 03, 2024