def main():
import os
import numpy as nm
import matplotlib.pyplot as plt
from sfepy.fem import MeshIO
import sfepy.linalg as la
from sfepy.mechanics.contact_bodies import ContactSphere, plot_points
conf_dir = os.path.dirname(__file__)
io = MeshIO.any_from_filename(filename_mesh, prefix_dir=conf_dir)
bb = io.read_bounding_box()
outline = [vv for vv in la.combine(zip(*bb))]
ax = plot_points(None, nm.array(outline), 'r*')
csc = materials['cs'][0]
cs = ContactSphere(csc['.c'], csc['.r'])
pps = (bb[1] - bb[0]) * nm.random.rand(5000, 3) + bb[0]
mask = cs.mask_points(pps, 0.0)
ax = plot_points(ax, cs.centre[None, :], 'b*', ms=30)
ax = plot_points(ax, pps[mask], 'kv')
ax = plot_points(ax, pps[~mask], 'r.')
plt.show()
def get_fargs(self,
force_pars,
centre,
radius,
virtual,
state,
mode=None,
term_mode=None,
diff_var=None,
**kwargs):
sg, _ = self.get_mapping(virtual)
assert_((force_pars >= 0.0).all(),
'force parameters must be non-negative!')
if self.cs is None:
self.cs = ContactSphere(centre, radius)
ig = self.char_fun.ig
qps = self.get_physical_qps()
qp_coors = qps.values[ig]
u_qp = self.get(state, 'val').reshape(qp_coors.shape)
# Deformed QP coordinates.
coors = u_qp + qp_coors
force = nm.zeros(coors.shape[0], dtype=nm.float64)
normals = nm.zeros((coors.shape[0], 3), dtype=nm.float64)
fd = None
k, f0, eps, a = self._get_force_pars(force_pars, force.shape)
# Active points in contact change with displacements!
ii = self.cs.mask_points(coors, nm.abs(eps.min()))
if diff_var is None:
if ii.any():
d, normals[ii] = self.cs.get_distance(coors[ii])
force[ii] = self.smooth_f(d, k[ii], f0[ii], a[ii], eps[ii], 0)
fmode = 0
else:
if ii.any():
d, normals[ii] = self.cs.get_distance(coors[ii])
# Force derivative.
force[ii] = self.smooth_f(d, k[ii], f0[ii], a[ii], eps[ii], 1)
# Force / (R - d).
aux = self.smooth_f(d, k[ii], f0[ii], a[ii], eps[ii], 0)
fd = nm.zeros_like(force)
fd[ii] = aux / (self.cs.radius - d)
fd.shape = qps.shape[ig][:2] + (1, 1)
fmode = 1
force.shape = qps.shape[ig][:2] + (1, 1)
normals.shape = qps.shape[ig][:2] + (3, 1)
return force, normals, fd, sg, fmode
