GetFEM  5.4.2
getfem_contact_and_friction_common.h
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1 /* -*- c++ -*- (enables emacs c++ mode) */
2 /*===========================================================================
3 
4  Copyright (C) 2011-2020 Yves Renard, Konstantinos Poulios.
5 
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30 ===========================================================================*/
31 
32 /** @file getfem_contact_and_friction_common.h
33  @author Yves Renard <Yves.Renard@insa-lyon.fr>
34  @author Konstantinos Poulios <logari81@googlemail.com>
35  @date November, 2011.
36  @brief Comomon tools for unilateral contact and Coulomb friction bricks.
37  */
38 #ifndef GETFEM_CONTACT_AND_FRICTION_COMMON_H__
39 #define GETFEM_CONTACT_AND_FRICTION_COMMON_H__
40 
41 #include "getfem_models.h"
42 #include "getfem_assembling_tensors.h"
43 #include "getfem/bgeot_rtree.h"
44 #include <getfem/getfem_mesher.h>
45 
46 
47 namespace getfem {
48 
49  //=========================================================================
50  //
51  // Projection on a ball and gradient of the projection.
52  //
53  //=========================================================================
54 
55  template<typename VEC> void ball_projection(const VEC &x,
56  scalar_type radius) {
57  if (radius <= scalar_type(0))
58  gmm::clear(const_cast<VEC&>(x));
59  else {
60  scalar_type a = gmm::vect_norm2(x);
61  if (a > radius) gmm::scale(const_cast<VEC&>(x), radius/a);
62  }
63  }
64 
65  template<typename VEC, typename VECR>
66  void ball_projection_grad_r(const VEC &x, scalar_type radius,
67  VECR &g) {
68  if (radius > scalar_type(0)) {
69  scalar_type a = gmm::vect_norm2(x);
70  if (a >= radius) {
71  gmm::copy(x, g); gmm::scale(g, scalar_type(1)/a);
72  return;
73  }
74  }
75  gmm::clear(g);
76  }
77 
78  template <typename VEC, typename MAT>
79  void ball_projection_grad(const VEC &x, scalar_type radius, MAT &g) {
80  if (radius <= scalar_type(0)) { gmm::clear(g); return; }
81  gmm::copy(gmm::identity_matrix(), g);
82  scalar_type a = gmm::vect_norm2(x);
83  if (a >= radius) {
84  gmm::scale(g, radius/a);
85  // gmm::rank_one_update(g, gmm::scaled(x, -radius/(a*a*a)), x);
86  for (size_type i = 0; i < x.size(); ++i)
87  for (size_type j = 0; j < x.size(); ++j)
88  g(i,j) -= radius*x[i]*x[j] / (a*a*a);
89  }
90  }
91 
92  template <typename VEC, typename VECR>
93  void coupled_projection(const VEC &x, const VEC &n,
94  scalar_type f, VECR &g) {
95  scalar_type xn = gmm::vect_sp(x, n);
96  scalar_type xnm = gmm::neg(xn);
97  scalar_type th = f * xnm;
98  scalar_type xtn = gmm::sqrt(gmm::vect_norm2_sqr(x) - xn*xn);
99 
100  gmm::copy(gmm::scaled(n, -xnm), g);
101  if (th > scalar_type(0)) {
102  if (xtn <= th) {
103  gmm::add(x, g);
104  gmm::add(gmm::scaled(n, -xn), g);
105  } else {
106  gmm::add(gmm::scaled(x, f*xnm/xtn), g);
107  gmm::add(gmm::scaled(n, -f*xnm*xn/xtn), g);
108  }
109  }
110  }
111 
112 
113  template <typename VEC, typename MAT>
114  void coupled_projection_grad(const VEC &x, const VEC &n,
115  scalar_type f, MAT &g) {
116  scalar_type xn = gmm::vect_sp(x, n);
117  scalar_type xnm = gmm::neg(xn);
118  scalar_type th = f * xnm;
119  scalar_type xtn = gmm::sqrt(gmm::vect_norm2_sqr(x) - xn*xn);
120  size_type N = gmm::vect_size(x);
121  gmm::clear(g);
122 
123  if (th > scalar_type(0)) {
124  if (xtn <= th) {
125  gmm::copy(gmm::identity_matrix(), g);
126  gmm::rank_one_update(g, gmm::scaled(n, -scalar_type(1)), n);
127  } else if (xn < scalar_type(0)) {
128  static base_small_vector t; gmm::resize(t, N);
129  gmm::add(x, gmm::scaled(n, -xn), t);
130  gmm::scale(t, scalar_type(1)/xtn);
131  if (N > 2) {
132  gmm::copy(gmm::identity_matrix(), g);
133  gmm::rank_one_update(g, gmm::scaled(t, -scalar_type(1)), t);
134  gmm::rank_one_update(g, gmm::scaled(n, -scalar_type(1)), n);
135  gmm::scale(g, -xn*th/xtn);
136  }
137  gmm::rank_one_update(g, gmm::scaled(t, -f), n);
138  }
139  }
140 
141  if (xn < scalar_type(0)) gmm::rank_one_update(g, n, n);
142  }
143 
144  //=========================================================================
145  //
146  // De Saxce projection and its gradients.
147  //
148  //=========================================================================
149 
150 
151  template<typename VEC>
152  void De_Saxce_projection(const VEC &x, const VEC &n_, scalar_type f) {
153  static base_small_vector n; // For more robustness, n_ is not supposed unitary
154  size_type N = gmm::vect_size(x);
155  gmm::resize(n, N);
156  gmm::copy(gmm::scaled(n_, scalar_type(1)/gmm::vect_norm2(n_)), n);
157  scalar_type xn = gmm::vect_sp(x, n);
158  scalar_type nxt = sqrt(gmm::abs(gmm::vect_norm2_sqr(x) - xn*xn));
159  if (xn >= scalar_type(0) && f * nxt <= xn) {
160  gmm::clear(const_cast<VEC&>(x));
161  } else if (xn > scalar_type(0) || nxt > -f*xn) {
162  gmm::add(gmm::scaled(n, -xn), const_cast<VEC&>(x));
163  gmm::scale(const_cast<VEC&>(x), -f / nxt);
164  gmm::add(n, const_cast<VEC&>(x));
165  gmm::scale(const_cast<VEC&>(x), (xn - f * nxt) / (f*f+scalar_type(1)));
166  }
167  }
168 
169  template<typename VEC, typename MAT>
170  void De_Saxce_projection_grad(const VEC &x, const VEC &n_,
171  scalar_type f, MAT &g) {
172  static base_small_vector n;
173  size_type N = gmm::vect_size(x);
174  gmm::resize(n, N);
175  gmm::copy(gmm::scaled(n_, scalar_type(1)/gmm::vect_norm2(n_)), n);
176  scalar_type xn = gmm::vect_sp(x, n);
177  scalar_type nxt = sqrt(gmm::abs(gmm::vect_norm2_sqr(x) - xn*xn));
178 
179 
180  if (xn > scalar_type(0) && f * nxt <= xn) {
181  gmm::clear(g);
182  } else if (xn > scalar_type(0) || nxt > -f*xn) {
183  static base_small_vector xt;
184  gmm::resize(xt, N);
185  gmm::add(x, gmm::scaled(n, -xn), xt);
186  gmm::scale(xt, scalar_type(1)/nxt);
187 
188  if (N > 2) {
189  gmm::copy(gmm::identity_matrix(), g);
190  gmm::rank_one_update(g, gmm::scaled(n, -scalar_type(1)), n);
191  gmm::rank_one_update(g, gmm::scaled(xt, -scalar_type(1)), xt);
192  gmm::scale(g, f*(f - xn/nxt));
193  } else {
194  gmm::clear(g);
195  }
196 
197  gmm::scale(xt, -f); gmm::add(n, xt);
198  gmm::rank_one_update(g, xt, xt);
199  gmm::scale(g, scalar_type(1) / (f*f+scalar_type(1)));
200  } else {
201  gmm::copy(gmm::identity_matrix(), g);
202  }
203  }
204 
205 
206  template<typename VEC, typename MAT>
207  static void De_Saxce_projection_gradn(const VEC &x, const VEC &n_,
208  scalar_type f, MAT &g) {
209  static base_small_vector n;
210  size_type N = gmm::vect_size(x);
211  scalar_type nn = gmm::vect_norm2(n_);
212  gmm::resize(n, N);
213  gmm::copy(gmm::scaled(n_, scalar_type(1)/nn), n);
214  scalar_type xn = gmm::vect_sp(x, n);
215  scalar_type nxt = sqrt(gmm::abs(gmm::vect_norm2_sqr(x) - xn*xn));
216  gmm::clear(g);
217 
218  if (!(xn > scalar_type(0) && f * nxt <= xn)
219  && (xn > scalar_type(0) || nxt > -f*xn)) {
220  static base_small_vector xt, aux;
221  gmm::resize(xt, N); gmm::resize(aux, N);
222  gmm::add(x, gmm::scaled(n, -xn), xt);
223  gmm::scale(xt, scalar_type(1)/nxt);
224 
225  scalar_type c = (scalar_type(1) + f*xn/nxt)/nn;
226  for (size_type i = 0; i < N; ++i) g(i,i) = c;
227  gmm::rank_one_update(g, gmm::scaled(n, -c), n);
228  gmm::rank_one_update(g, gmm::scaled(n, f/nn), xt);
229  gmm::rank_one_update(g, gmm::scaled(xt, -f*xn/(nn*nxt)), xt);
230  gmm::scale(g, xn - f*nxt);
231 
232  gmm::add(gmm::scaled(xt, -f), n, aux);
233  gmm::rank_one_update(g, aux, gmm::scaled(xt, (nxt+f*xn)/nn));
234 
235  gmm::scale(g, scalar_type(1) / (f*f+scalar_type(1)));
236  }
237  }
238 
239  //=========================================================================
240  //
241  // Some basic assembly functions.
242  //
243  //=========================================================================
244 
245  template <typename MAT1, typename MAT2>
246  void mat_elem_assembly(const MAT1 &M_, const MAT2 &Melem,
247  const mesh_fem &mf1, size_type cv1,
248  const mesh_fem &mf2, size_type cv2) {
249  MAT1 &M = const_cast<MAT1 &>(M_);
250  typedef typename gmm::linalg_traits<MAT1>::value_type T;
251  T val;
252  mesh_fem::ind_dof_ct cvdof1 = mf1.ind_basic_dof_of_element(cv1);
253  mesh_fem::ind_dof_ct cvdof2 = mf2.ind_basic_dof_of_element(cv2);
254 
255  GMM_ASSERT1(cvdof1.size() == gmm::mat_nrows(Melem)
256  && cvdof2.size() == gmm::mat_ncols(Melem),
257  "Dimensions mismatch");
258 
259  if (mf1.is_reduced()) {
260  if (mf2.is_reduced()) {
261  for (size_type i = 0; i < cvdof1.size(); ++i)
262  for (size_type j = 0; j < cvdof2.size(); ++j)
263  if ((val = Melem(i,j)) != T(0))
264  asmrankoneupdate
265  (M, gmm::mat_row(mf1.extension_matrix(), cvdof1[i]),
266  gmm::mat_row(mf2.extension_matrix(), cvdof2[j]), val);
267  } else {
268  for (size_type i = 0; i < cvdof1.size(); ++i)
269  for (size_type j = 0; j < cvdof2.size(); ++j)
270  if ((val = Melem(i,j)) != T(0))
271  asmrankoneupdate
272  (M, gmm::mat_row(mf1.extension_matrix(), cvdof1[i]),
273  cvdof2[j], val);
274  }
275  } else {
276  if (mf2.is_reduced()) {
277  for (size_type i = 0; i < cvdof1.size(); ++i)
278  for (size_type j = 0; j < cvdof2.size(); ++j)
279  if ((val = Melem(i,j)) != T(0))
280  asmrankoneupdate
281  (M, cvdof1[i],
282  gmm::mat_row(mf2.extension_matrix(), cvdof2[j]), val);
283  } else {
284  for (size_type i = 0; i < cvdof1.size(); ++i)
285  for (size_type j = 0; j < cvdof2.size(); ++j)
286  if ((val = Melem(i,j)) != T(0))
287  M(cvdof1[i], cvdof2[j]) += val;
288  }
289  }
290  }
291 
292 
293  template <typename VEC1, typename VEC2>
294  void vec_elem_assembly(const VEC1 &V_, const VEC2 &Velem,
295  const mesh_fem &mf, size_type cv) {
296  VEC1 &V = const_cast<VEC1 &>(V_);
297  typedef typename gmm::linalg_traits<VEC1>::value_type T;
298  std::vector<size_type> cvdof(mf.ind_basic_dof_of_element(cv).begin(),
299  mf.ind_basic_dof_of_element(cv).end());
300 
301  GMM_ASSERT1(cvdof.size() == gmm::vect_size(Velem), "Dimensions mismatch");
302 
303  if (mf.is_reduced()) {
304  T val;
305  for (size_type i = 0; i < cvdof.size(); ++i)
306  if ((val = Velem[i]) != T(0))
307  gmm::add(gmm::scaled(gmm::mat_row(mf.extension_matrix(), cvdof[i]),
308  val), V);
309  } else {
310  for (size_type i = 0; i < cvdof.size(); ++i) V[cvdof[i]] += Velem[i];
311  }
312  }
313 
314  template <typename MAT1, typename MAT2>
315  void mat_elem_assembly(const MAT1 &M_, const gmm::sub_interval &I1,
316  const gmm::sub_interval &I2,
317  const MAT2 &Melem,
318  const mesh_fem &mf1, size_type cv1,
319  const mesh_fem &mf2, size_type cv2) {
320  MAT1 &M = const_cast<MAT1 &>(M_);
321  typedef typename gmm::linalg_traits<MAT1>::value_type T;
322  T val;
323 
324  mesh_fem::ind_dof_ct cvdof1 = mf1.ind_basic_dof_of_element(cv1);
325  mesh_fem::ind_dof_ct cvdof2 = mf2.ind_basic_dof_of_element(cv2);
326 
327  GMM_ASSERT1(cvdof1.size() == gmm::mat_nrows(Melem)
328  && cvdof2.size() == gmm::mat_ncols(Melem),
329  "Dimensions mismatch");
330 
331  if (mf1.is_reduced()) {
332  if (mf2.is_reduced()) {
333  for (size_type i = 0; i < cvdof1.size(); ++i)
334  for (size_type j = 0; j < cvdof2.size(); ++j)
335  if ((val = Melem(i,j)) != T(0))
336  asmrankoneupdate
337  (gmm::sub_matrix(M, I1, I2),
338  gmm::mat_row(mf1.extension_matrix(), cvdof1[i]),
339  gmm::mat_row(mf2.extension_matrix(), cvdof2[j]), val);
340  } else {
341  for (size_type i = 0; i < cvdof1.size(); ++i)
342  for (size_type j = 0; j < cvdof2.size(); ++j)
343  if ((val = Melem(i,j)) != T(0))
344  asmrankoneupdate
345  (gmm::sub_matrix(M, I1, I2),
346  gmm::mat_row(mf1.extension_matrix(), cvdof1[i]),
347  cvdof2[j], val);
348  }
349  } else {
350  if (mf2.is_reduced()) {
351  for (size_type i = 0; i < cvdof1.size(); ++i)
352  for (size_type j = 0; j < cvdof2.size(); ++j)
353  if ((val = Melem(i,j)) != T(0))
354  asmrankoneupdate
355  (gmm::sub_matrix(M, I1, I2), cvdof1[i],
356  gmm::mat_row(mf2.extension_matrix(), cvdof2[j]), val);
357  } else {
358  for (size_type i = 0; i < cvdof1.size(); ++i)
359  for (size_type j = 0; j < cvdof2.size(); ++j)
360  if ((val = Melem(i,j)) != T(0))
361  M(cvdof1[i]+I1.first(), cvdof2[j]+I2.first()) += val;
362  }
363  }
364  }
365 
366  template <typename VEC1, typename VEC2>
367  void vec_elem_assembly(const VEC1 &V_, const gmm::sub_interval &I,
368  const VEC2 &Velem, const mesh_fem &mf, size_type cv) {
369  VEC1 &V = const_cast<VEC1 &>(V_);
370  typedef typename gmm::linalg_traits<VEC1>::value_type T;
371  std::vector<size_type> cvdof(mf.ind_basic_dof_of_element(cv).begin(),
372  mf.ind_basic_dof_of_element(cv).end());
373 
374  GMM_ASSERT1(cvdof.size() == gmm::vect_size(Velem), "Dimensions mismatch");
375 
376  if (mf.is_reduced()) {
377  T val;
378  for (size_type i = 0; i < cvdof.size(); ++i)
379  if ((val = Velem[i]) != T(0))
380  gmm::add(gmm::scaled(gmm::mat_row(mf.extension_matrix(), cvdof[i]),
381  val), gmm::sub_vector(V, I));
382  } else {
383  for (size_type i = 0; i < cvdof.size(); ++i)
384  V[I.first()+cvdof[i]] += Velem[i];
385  }
386  }
387 
388 
389  void compute_normal(const fem_interpolation_context &ctx, size_type face,
390  bool in_reference_conf, const model_real_plain_vector &coeff,
391  base_node &n0, base_node &n, base_matrix &grad);
392 
393  //=========================================================================
394  //
395  // Structure which stores the contact boundaries, rigid obstacles and
396  // computes the contact pairs in large sliding/large deformation
397  //
398  // Deprecated
399  //
400  //=========================================================================
401 
402 
403  class multi_contact_frame {
404 
405  // Structure describing a contact boundary
406  struct contact_boundary {
407  size_type region; // Boundary number
408  const getfem::mesh_fem *mfu; // F.e.m. for the displacement.
409  const getfem::mesh_fem *mflambda; // F.e.m. for the displacement.
410  const getfem::mesh_im *mim; // Integration method for the boundary.
411  std::string multname; // Name of the optional contact stress
412  // multiplier when linked to a model.
413  size_type ind_U; // Index of displacement.
414  size_type ind_lambda; // Index of multiplier (if any).
415  bool slave;
416  contact_boundary(void) {}
417  contact_boundary(size_type r, const mesh_fem *mf,
418  const mesh_im &mi, size_type i_U, const mesh_fem *mfl,
419  size_type i_l = size_type(-1))
420  : region(r), mfu(mf), mflambda(mfl), mim(&mi),
421  ind_U(i_U), ind_lambda(i_l), slave(false) {}
422  };
423 
424 
425  size_type N; // Meshes dimensions
426  bool self_contact; // Self-contact is searched or not.
427  bool ref_conf; // Contact in reference configuration
428  // for linear elasticity small sliding contact.
429  bool use_delaunay; // Use delaunay to detect the contact pairs instead
430  // of influence boxes.
431  int nodes_mode; // 0 = Use Gauss points for both slave and master
432  // 1 = Use finite element nodes for slave and
433  // Gauss points for master.
434  // 2 = Use finite element nodes for both slave
435  // and master
436  bool raytrace; // Use raytrace instead of projection.
437 
438  scalar_type release_distance; // Limit distance beyond which the contact
439  // will not be considered. CAUTION: should be comparable to the element
440  // size (if it is too large, a too large set of influence boxes will be
441  // detected and the computation will be slow, except for delaunay option)
442 
443  scalar_type cut_angle; // Cut angle (in radian) for normal cones
444  scalar_type EPS; // Should be typically hmin/1000 (for computing
445  // gradients with finite differences
446  const model *md; // The model if the structure is linked to a model.
447 
448  typedef model_real_plain_vector VECTOR;
449  std::vector<const VECTOR *> Us; // Displacement vectors
450  std::vector<const VECTOR *> Ws; // "Velocity" vectors
451  std::vector<std::string> Unames; // Displacement vectors names.
452  std::vector<std::string> Wnames; // "Velocity" vectors names.
453  std::vector<VECTOR> ext_Us; // Unreduced displacement vectors
454  std::vector<VECTOR> ext_Ws; // Unreduced "velocity" vectors
455  std::vector<const VECTOR *> lambdas; // Displacement vectors
456  std::vector<std::string> lambdanames; // Displacement vectors names.
457  std::vector<VECTOR> ext_lambdas; // Unreduced displacement vectors
458 
459  std::vector<contact_boundary> contact_boundaries;
460 
461  std::vector<std::string> coordinates;
462  model_real_plain_vector pt, ptx, pty, ptz, ptw;
463  std::list<ga_workspace> obstacles_gw;
464  std::vector<ga_function> obstacles_f;
465  std::vector<std::string> obstacles;
466  std::vector<std::string> obstacles_velocities;
467 
468 
469  struct normal_cone : public std::vector<base_small_vector> {
470 
471  void add_normal(const base_small_vector &n)
472  { std::vector<base_small_vector>::push_back(n);}
473  normal_cone(void) {}
474  normal_cone(const base_small_vector &n)
475  : std::vector<base_small_vector>(1, n) { }
476  };
477 
478  //
479  // Influence boxes
480  //
481  struct influence_box { // Additional information for an influence box
482  size_type ind_boundary; // Boundary number
483  size_type ind_element; // Element number
484  short_type ind_face; // Face number in element
485  base_small_vector mean_normal; // Mean outward normal unit vector
486  influence_box(void) {}
487  influence_box(size_type ib, size_type ie,
488  short_type iff, const base_small_vector &n)
489  : ind_boundary(ib), ind_element(ie), ind_face(iff), mean_normal(n) {}
490  };
491 
492  bgeot::rtree element_boxes; // influence boxes
493  std::vector<influence_box> element_boxes_info;
494 
495  //
496  // Stored points (for Delaunay and slave nodal boundaries)
497  //
498 
499  struct boundary_point { // Additional information for a boundary point
500  base_node ref_point; // Point coordinate in reference configuration
501  size_type ind_boundary; // Boundary number
502  size_type ind_element; // Element number
503  short_type ind_face; // Face number in element
504  size_type ind_pt; // Dof number for fem nodes or point number
505  // of integration method (depending on nodes_mode)
506  normal_cone normals; // Set of outward unit normal vectors
507  boundary_point(void) {}
508  boundary_point(const base_node &rp, size_type ib, size_type ie,
509  short_type iff, size_type id, const base_small_vector &n)
510  : ref_point(rp), ind_boundary(ib), ind_element(ie), ind_face(iff),
511  ind_pt(id), normals(n) {}
512  };
513 
514  std::vector<base_node> boundary_points;
515  std::vector<boundary_point> boundary_points_info;
516 
517 
518  size_type add_U(const model_real_plain_vector *U, const std::string &name,
519  const model_real_plain_vector *w, const std::string &wname);
520  size_type add_lambda(const model_real_plain_vector *lambda,
521  const std::string &name);
522 
523  void extend_vectors(void);
524 
525  void normal_cone_simplification(void);
526 
527  bool test_normal_cones_compatibility(const normal_cone &nc1,
528  const normal_cone &nc2);
529 
530  bool test_normal_cones_compatibility(const base_small_vector &n,
531  const normal_cone &nc2);
532 
533  dal::bit_vector aux_dof_cv; // An auxiliary variable for are_dof_linked
534  // function (in order to be of constant complexity).
535 
536  bool are_dof_linked(size_type ib1, size_type idof1,
537  size_type ib2, size_type idof2);
538 
539  bool is_dof_linked(size_type ib1, size_type idof1,
540  size_type ib2, size_type cv);
541  public:
542 
543  struct face_info {
544  size_type ind_boundary;
545  size_type ind_element;
546  short_type ind_face;
547  face_info(void) {}
548  face_info(size_type ib, size_type ie, short_type iff)
549  : ind_boundary(ib), ind_element(ie), ind_face(iff) {}
550  };
551 
552  protected:
553 
554  std::vector<std::vector<face_info> > potential_pairs;
555 
556  void add_potential_contact_face(size_type ip, size_type ib, size_type ie,
557  short_type iff);
558  public:
559 
560  // stored information for contact pair
561  struct contact_pair {
562 
563  base_node slave_point; // The transformed slave point
564  base_small_vector slave_n; // Normal unit vector to slave surface
565  size_type slave_ind_boundary; // Boundary number
566  size_type slave_ind_element; // Element number
567  short_type slave_ind_face; // Face number in element
568  size_type slave_ind_pt; // Dof number for fem nodes or point number
569  // of integration method (depending on nodes_mode)
570 
571  base_node master_point_ref; // The master point on ref element
572  base_node master_point; // The transformed master point
573  base_small_vector master_n; // Normal unit vector to master surface
574  size_type master_ind_boundary; // Boundary number
575  size_type master_ind_element; // Element number
576  short_type master_ind_face; // Face number in element
577 
578  scalar_type signed_dist;
579 
580  size_type irigid_obstacle;
581 
582  contact_pair(void) {}
583  contact_pair(const base_node &spt, const base_small_vector &nx,
584  const boundary_point &bp,
585  const base_node &mptr, const base_node &mpt,
586  const base_small_vector &ny,
587  const face_info &mfi, scalar_type sd)
588  : slave_point(spt), slave_n(nx),
589  slave_ind_boundary(bp.ind_boundary), slave_ind_element(bp.ind_element),
590  slave_ind_face(bp.ind_face), slave_ind_pt(bp.ind_pt),
591  master_point_ref(mptr), master_point(mpt), master_n(ny),
592  master_ind_boundary(mfi.ind_boundary), master_ind_element(mfi.ind_element),
593  master_ind_face(mfi.ind_face),
594  signed_dist(sd), irigid_obstacle(size_type(-1)) {}
595  contact_pair(const base_node &spt, const base_small_vector &nx,
596  const boundary_point &bp,
597  const base_node &mpt, const base_small_vector &ny,
598  size_type ir, scalar_type sd)
599  : slave_point(spt), slave_n(nx), slave_ind_boundary(bp.ind_boundary),
600  slave_ind_element(bp.ind_element), slave_ind_face(bp.ind_face),
601  slave_ind_pt(bp.ind_pt), master_point(mpt), master_n(ny),
602  signed_dist(sd),
603  irigid_obstacle(ir) {}
604 
605  };
606 
607 
608  // Compute the influence boxes of master boundary elements. To be run
609  // before the detection of contact pairs. The influence box is the
610  // bounding box extended by a distance equal to the release distance.
611  void compute_influence_boxes(void);
612 
613  // For delaunay triangulation. Advantages compared to influence boxes:
614  // No degeneration of the algorithm complexity with refinement and
615  // more easy to extend to fictitious domain with contact.
616  // Stores all the boundary deformed points relatively to
617  // an integration method or to finite element nodes (depending on
618  // nodes_mode). Storing sufficient information to perform
619  // a Delaunay triangulation and to be able to recover the boundary
620  // number, element number, face number, unit normal vector ...
621  void compute_boundary_points(bool slave_only = false);
622  void compute_potential_contact_pairs_delaunay(void);
623  void compute_potential_contact_pairs_influence_boxes(void);
624 
625  protected:
626 
627  std::vector<contact_pair> contact_pairs;
628 
629  void clear_aux_info(void); // Delete auxiliary information
630 
631  public:
632 
633  size_type dim(void) const { return N; }
634  const std::vector<contact_pair> &ct_pairs(void) const
635  { return contact_pairs; }
636 
637 
638  const getfem::mesh_fem &mfdisp_of_boundary(size_type n) const
639  { return *(contact_boundaries[n].mfu); }
640  const getfem::mesh_fem &mfmult_of_boundary(size_type n) const
641  { return *(contact_boundaries[n].mflambda); }
642  const getfem::mesh_im &mim_of_boundary(size_type n) const
643  { return *(contact_boundaries[n].mim); }
644  size_type nb_variables(void) const { return Us.size(); }
645  size_type nb_multipliers(void) const { return lambdas.size(); }
646  const std::string &varname(size_type i) const { return Unames[i]; }
647  const std::string &multname(size_type i) const { return lambdanames[i]; }
648  const model_real_plain_vector &disp_of_boundary(size_type n) const
649  { return ext_Us[contact_boundaries[n].ind_U]; }
650  const model_real_plain_vector &disp0_of_boundary(size_type n) const
651  { return ext_Ws[contact_boundaries[n].ind_U]; }
652  const model_real_plain_vector &mult_of_boundary(size_type n) const
653  { return ext_lambdas[contact_boundaries[n].ind_lambda]; }
654  size_type region_of_boundary(size_type n) const
655  { return contact_boundaries[n].region; }
656  const std::string &varname_of_boundary(size_type n) const
657  { return Unames[contact_boundaries[n].ind_U]; }
658  size_type ind_varname_of_boundary(size_type n) const
659  { return contact_boundaries[n].ind_U; }
660  const std::string &multname_of_boundary(size_type n) const {
661  static const std::string vname;
662  size_type ind = contact_boundaries[n].ind_lambda;
663  return (ind == size_type(-1)) ? vname : lambdanames[ind];
664  }
665  size_type ind_multname_of_boundary(size_type n) const
666  { return contact_boundaries[n].ind_lambda; }
667  size_type nb_boundaries(void) const { return contact_boundaries.size(); }
668  bool is_self_contact(void) const { return self_contact; }
669  bool is_slave_boundary(size_type n) const { return contact_boundaries[n].slave; }
670  void set_raytrace(bool b) { raytrace = b; }
671  void set_nodes_mode(int m) { nodes_mode = m; }
672  size_type nb_contact_pairs(void) const { return contact_pairs.size(); }
673  const contact_pair &get_contact_pair(size_type i)
674  { return contact_pairs[i]; }
675 
676  multi_contact_frame(size_type NN, scalar_type r_dist,
677  bool dela = true, bool selfc = true,
678  scalar_type cut_a = 0.3, bool rayt = false,
679  int fem_nodes = 0, bool refc = false);
680  multi_contact_frame(const model &md, size_type NN, scalar_type r_dist,
681  bool dela = true, bool selfc = true,
682  scalar_type cut_a = 0.3, bool rayt = false,
683  int fem_nodes = 0, bool refc = false);
684 
685  size_type add_obstacle(const std::string &obs);
686 
687  size_type add_slave_boundary(const getfem::mesh_im &mim,
688  const getfem::mesh_fem *mfu,
689  const model_real_plain_vector *U,
690  size_type reg,
691  const getfem::mesh_fem *mflambda = 0,
692  const model_real_plain_vector *lambda = 0,
693  const model_real_plain_vector *w = 0,
694  const std::string &varname = std::string(),
695  const std::string &multname = std::string(),
696  const std::string &wname = std::string());
697 
698  size_type add_slave_boundary(const getfem::mesh_im &mim, size_type reg,
699  const std::string &varname,
700  const std::string &multname = std::string(),
701  const std::string &wname = std::string());
702 
703 
704  size_type add_master_boundary(const getfem::mesh_im &mim,
705  const getfem::mesh_fem *mfu,
706  const model_real_plain_vector *U,
707  size_type reg,
708  const getfem::mesh_fem *mflambda = 0,
709  const model_real_plain_vector *lambda = 0,
710  const model_real_plain_vector *w = 0,
711  const std::string &varname = std::string(),
712  const std::string &multname = std::string(),
713  const std::string &wname = std::string());
714 
715  size_type add_master_boundary(const getfem::mesh_im &mim, size_type reg,
716  const std::string &varname,
717  const std::string &multname = std::string(),
718  const std::string &wname = std::string());
719 
720 
721 
722  // The whole process of the computation of contact pairs
723  // Contact pairs are seached for a certain boundary (master or slave,
724  // depending on the contact algorithm) on the master ones. If contact pairs
725  // are searched for a master boundary, self-contact is taken into account
726  // if the flag 'self_contact' is set to 'true'. Self-contact is never taken
727  // into account for a slave boundary.
728  void compute_contact_pairs(void);
729 
730  };
731 
732 
733 
734  //=========================================================================
735  //
736  // Raytracing Interpolate transformation
737  //
738  //=========================================================================
739 
740  /** Add a raytracing interpolate transformation called 'transname' to a model
741  to be used by the generic assembly bricks.
742  */
743  void add_raytracing_transformation
744  (model &md, const std::string &transname, scalar_type release_distance);
745 
746  /** Add a raytracing interpolate transformation called 'transname' to a
747  workspace to be used by the generic assembly bricks.
748  */
749  void add_raytracing_transformation
750  (ga_workspace &workspace, const std::string &transname,
751  scalar_type release_distance);
752 
753  /** Add a master boundary with corresponding displacement variable
754  'dispname' on a specific boundary 'region' to an existing raytracing
755  interpolate transformation called 'transname'.
756  */
757  void add_master_contact_boundary_to_raytracing_transformation
758  (model &md, const std::string &transname,const mesh &m,
759  const std::string &dispname, size_type region);
760 
761  /** Add a slave boundary with corresponding displacement variable
762  'dispname' on a specific boundary 'region' to an existing raytracing
763  interpolate transformation called 'transname'.
764  */
765  void add_slave_contact_boundary_to_raytracing_transformation
766  (model &md, const std::string &transname, const mesh &m,
767  const std::string &dispname, size_type region);
768 
769  /** Add a master boundary with corresponding displacement variable
770  'dispname' on a specific boundary 'region' to an existing raytracing
771  interpolate transformation called 'transname'.
772  */
773  void add_master_contact_boundary_to_raytracing_transformation
774  (ga_workspace &workspace, const std::string &transname, const mesh &m,
775  const std::string &dispname, size_type region);
776 
777  /** Add a slave boundary with corresponding displacement variable
778  'dispname' on a specific boundary 'region' to an existing raytracing
779  interpolate transformation called 'transname'.
780  */
781  void add_slave_contact_boundary_to_raytracing_transformation
782  (ga_workspace &workspace, const std::string &transname, const mesh &m,
783  const std::string &dispname, size_type region);
784 
785  /** Add a rigid obstacle whose geometry corresponds to the zero level-set
786  of the high-level generic assembly expression `expr`
787  to an existing raytracing interpolate transformation called 'transname'.
788  In `expr`, the current position is denoted `X` with components
789  `X(1), X(2), ...`. It is also allowed to use `x` instead of `X(1)`,
790  `y` instead of `X(2)`, `z` instead of `X(3)` and `w` instead of `X(4)`.
791  */
792  void add_rigid_obstacle_to_raytracing_transformation
793  (model &md, const std::string &transname,
794  const std::string &expr, size_type N);
795 
796  /** Add a rigid obstacle whose geometry corresponds to the zero level-set
797  of the high-level generic assembly expression 'expr'
798  to an existing raytracing interpolate transformation called 'transname'.
799  */
800  void add_rigid_obstacle_to_raytracing_transformation
801  (ga_workspace &workspace, const std::string &transname,
802  const std::string &expr, size_type N);
803 
804  //=========================================================================
805  //
806  // Projection Interpolate transformation
807  //
808  //=========================================================================
809 
810  /** Add a projection interpolate transformation called 'transname' to a model
811  to be used by the generic assembly bricks.
812  */
813  void add_projection_transformation
814  (model &md, const std::string &transname, scalar_type release_distance);
815 
816  /** Add a projection interpolate transformation called 'transname' to a
817  workspace to be used by the generic assembly bricks.
818  */
819  void add_projection_transformation
820  (ga_workspace &workspace, const std::string &transname,
821  scalar_type release_distance);
822 
823  /** Add a master boundary with corresponding displacement variable
824  'dispname' on a specific boundary 'region' to an existing projection
825  interpolate transformation called 'transname'.
826  */
827  void add_master_contact_boundary_to_projection_transformation
828  (model &md, const std::string &transname,const mesh &m,
829  const std::string &dispname, size_type region);
830  /** Add a master boundary with corresponding displacement variable
831  'dispname' on a specific boundary 'region' to an existing projection
832  interpolate transformation called 'transname'.
833  */
834  void add_master_contact_boundary_to_projection_transformation
835  (ga_workspace &workspace, const std::string &transname, const mesh &m,
836  const std::string &dispname, size_type region);
837 
838  /** Add a slave boundary with corresponding displacement variable
839  'dispname' on a specific boundary 'region' to an existing projection
840  interpolate transformation called 'transname'.
841  */
842  void add_slave_contact_boundary_to_projection_transformation
843  (model &md, const std::string &transname, const mesh &m,
844  const std::string &dispname, size_type region);
845 
846  /** Add a slave boundary with corresponding displacement variable
847  'dispname' on a specific boundary 'region' to an existing projection
848  interpolate transformation called 'transname'.
849  */
850  void add_slave_contact_boundary_to_projection_transformation
851  (ga_workspace &workspace, const std::string &transname, const mesh &m,
852  const std::string &dispname, size_type region);
853 
854  /** Add a rigid obstacle whose geometry corresponds to the zero level-set
855  of the high-level generic assembly expression `expr`
856  to an existing projection interpolate transformation called 'transname'.
857  In `expr`, the current position is denoted `X` with components
858  `X(1), X(2), ...`. It is also allowed to use `x` instead of `X(1)`,
859  `y` instead of `X(2)`, `z` instead of `X(3)` and `w` instead of `X(4)`.
860  */
861  void add_rigid_obstacle_to_projection_transformation
862  (model &md, const std::string &transname,
863  const std::string &expr, size_type N);
864 
865  /** Add a rigid obstacle whose geometry corresponds to the zero level-set
866  of the high-level generic assembly expression 'expr'
867  to an existing projection interpolate transformation called 'transname'.
868  */
869  void add_rigid_obstacle_to_projection_transformation
870  (ga_workspace &workspace, const std::string &transname,
871  const std::string &expr, size_type N);
872 } /* end of namespace getfem. */
873 
874 
875 #endif /* GETFEM_CONTACT_AND_FRICTION_COMMON_H__ */
bgeot::compute_normal
base_small_vector compute_normal(const geotrans_interpolation_context &c, size_type face)
norm of returned vector is the ratio between the face surface on the real element and the face surfac...
Definition: bgeot_geometric_trans.cc:1082
getfem::add_rigid_obstacle_to_projection_transformation
void add_rigid_obstacle_to_projection_transformation(model &md, const std::string &transname, const std::string &expr, size_type N)
Add a rigid obstacle whose geometry corresponds to the zero level-set of the high-level generic assem...
Definition: getfem_contact_and_friction_common.cc:2554
getfem_assembling_tensors.h
Generic assembly implementation.
gmm::resize
void resize(M &v, size_type m, size_type n)
*‍/
Definition: gmm_blas.h:231
getfem::add_projection_transformation
void add_projection_transformation(model &md, const std::string &transname, scalar_type release_distance)
Add a projection interpolate transformation called 'transname' to a model to be used by the generic a...
Definition: getfem_contact_and_friction_common.cc:2500
bgeot::size_type
size_t size_type
used as the common size type in the library
Definition: bgeot_poly.h:49
gmm::clear
void clear(L &l)
clear (fill with zeros) a vector or matrix.
Definition: gmm_blas.h:59
getfem::mesh_im
Describe an integration method linked to a mesh.
Definition: getfem_mesh_im.h:47
getfem::add_master_contact_boundary_to_projection_transformation
void add_master_contact_boundary_to_projection_transformation(model &md, const std::string &transname, const mesh &m, const std::string &dispname, size_type region)
Add a master boundary with corresponding displacement variable 'dispname' on a specific boundary 'reg...
Definition: getfem_contact_and_friction_common.cc:2514
getfem_mesher.h
An experimental mesher.
getfem::mesh_fem
Describe a finite element method linked to a mesh.
Definition: getfem_mesh_fem.h:148
getfem::add_slave_contact_boundary_to_raytracing_transformation
void add_slave_contact_boundary_to_raytracing_transformation(model &md, const std::string &transname, const mesh &m, const std::string &dispname, size_type region)
Add a slave boundary with corresponding displacement variable 'dispname' on a specific boundary 'regi...
Definition: getfem_contact_and_friction_common.cc:2450
bgeot::short_type
gmm::uint16_type short_type
used as the common short type integer in the library
Definition: bgeot_config.h:72
bgeot::rtree
Balanced tree of n-dimensional rectangles.
Definition: bgeot_rtree.h:98
getfem
GEneric Tool for Finite Element Methods.
Definition: getfem_accumulated_distro.h:46
bgeot_rtree.h
region-tree for window/point search on a set of rectangles.
getfem_models.h
Model representation in Getfem.
getfem::add_raytracing_transformation
void add_raytracing_transformation(model &md, const std::string &transname, scalar_type release_distance)
Add a raytracing interpolate transformation called 'transname' to a model to be used by the generic a...
Definition: getfem_contact_and_friction_common.cc:2426
gmm::vect_norm2
number_traits< typename linalg_traits< V >::value_type >::magnitude_type vect_norm2(const V &v)
Euclidean norm of a vector.
Definition: gmm_blas.h:557
getfem::add_master_contact_boundary_to_raytracing_transformation
void add_master_contact_boundary_to_raytracing_transformation(model &md, const std::string &transname, const mesh &m, const std::string &dispname, size_type region)
Add a master boundary with corresponding displacement variable 'dispname' on a specific boundary 'reg...
Definition: getfem_contact_and_friction_common.cc:2440
getfem::add_slave_contact_boundary_to_projection_transformation
void add_slave_contact_boundary_to_projection_transformation(model &md, const std::string &transname, const mesh &m, const std::string &dispname, size_type region)
Add a slave boundary with corresponding displacement variable 'dispname' on a specific boundary 'regi...
Definition: getfem_contact_and_friction_common.cc:2524
getfem::add_rigid_obstacle_to_raytracing_transformation
void add_rigid_obstacle_to_raytracing_transformation(model &md, const std::string &transname, const std::string &expr, size_type N)
Add a rigid obstacle whose geometry corresponds to the zero level-set of the high-level generic assem...
Definition: getfem_contact_and_friction_common.cc:2480

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