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contact_detector_inline_impl.cc
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			/**
			* @file contact_detection.hh
			*
			* @author Mohit Pundir <mohit.pundir@epfl.ch>
			*
			* @date creation: Mon Apr 29 2019
			* @date last modification: Mon Apr 29 2019
			*
			* @brief inine implementation of the contact detector class
			*
			* @section LICENSE
			*
			* Copyright (©) 2010-2018 EPFL (Ecole Polytechnique Fédérale de Lausanne)
			* Laboratory (LSMS - Laboratoire de Simulation en Mécanique des Solides)
			*
			* Akantu is free software: you can redistribute it and/or modify it under the
			* terms of the GNU Lesser General Public License as published by the Free
			* Software Foundation, either version 3 of the License, or (at your option) any
			* later version.
			*
			* Akantu is distributed in the hope that it will be useful, but WITHOUT ANY
			* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
			* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
			* details.
			*
			* You should have received a copy of the GNU Lesser General Public License
			* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
			*
			*/

			/* -------------------------------------------------------------------------- */
			#include "contact_detector.hh"
			/* -------------------------------------------------------------------------- */

			#ifndef __AKANTU_CONTACT_DETECTOR_INLINE_IMPL_CC__
			#define __AKANTU_CONTACT_DETECTOR_INLINE_IMPL_CC__

			namespace akantu {

			/* -------------------------------------------------------------------------- */
			inline bool
			ContactDetector::checkValidityOfProjection(Vector<Real> & projection) {

			UInt nb_xi_inside = 0;
			Real tolerance = 1e-3;

			for (auto xi : projection) {
			if (xi >= -1.0 - tolerance and xi <= 1.0 + tolerance)
			nb_xi_inside++;
			}

			if (nb_xi_inside == projection.size())
			return true;

			return false;
			}

			/* -------------------------------------------------------------------------- */
			inline void ContactDetector::coordinatesOfElement(const Element & el,
			Matrix<Real> & coords) {

			UInt nb_nodes_per_element = Mesh::getNbNodesPerElement(el.type);
			Vector<UInt> connect = mesh.getConnectivity(el.type, _not_ghost)
			.begin(nb_nodes_per_element)[el.element];

			for (UInt n = 0; n < nb_nodes_per_element; ++n) {
			UInt node = connect[n];
			for (UInt s : arange(spatial_dimension)) {
			coords(s, n) = this->positions(node, s);
			}
			}
			}

			/* -------------------------------------------------------------------------- */
			inline void ContactDetector::computeCellSpacing(Vector<Real> & spacing) {
			for (UInt s : arange(spatial_dimension))
			spacing(s) = std::sqrt(2.0) * max_dd;
			}

			/* -------------------------------------------------------------------------- */
			inline void
			ContactDetector::constructBoundingBox(BBox & bbox,
			const Array<UInt> & nodes_list) {

			auto to_bbox = [&](UInt node) {
			Vector<Real> pos(spatial_dimension);
			for (UInt s : arange(spatial_dimension)) {
			pos(s) = this->positions(node, s);
			}
			bbox += pos;
			};

			std::for_each(nodes_list.begin(), nodes_list.end(), to_bbox);

			auto & lower_bound = bbox.getLowerBounds();
			auto & upper_bound = bbox.getUpperBounds();

			for (UInt s : arange(spatial_dimension)) {
			lower_bound(s) -= this->max_bb;
			upper_bound(s) += this->max_bb;
			}

			AKANTU_DEBUG_INFO("BBox" << bbox);
			}

			/* -------------------------------------------------------------------------- */
			inline void ContactDetector::constructGrid(SpatialGrid<UInt> & grid,
			BBox & bbox,
			const Array<UInt> & nodes_list) {
			auto to_grid = [&](UInt node) {
			Vector<Real> pos(spatial_dimension);
			for (UInt s : arange(spatial_dimension)) {
			pos(s) = this->positions(node, s);
			}

			if (bbox.contains(pos)) {
			grid.insert(node, pos);
			}
			};

			std::for_each(nodes_list.begin(), nodes_list.end(), to_grid);
			}

			/* -------------------------------------------------------------------------- */
			inline void ContactDetector::computeMaximalDetectionDistance() {

			AKANTU_DEBUG_IN();

			Real elem_size;
			Real max_elem_size = std::numeric_limits<Real>::min();
			Real min_elem_size = std::numeric_limits<Real>::max();

			auto & master_nodes = this->surface_selector->getMasterList();

			for (auto & master : master_nodes) {
			Array<Element> elements;
			this->mesh.getAssociatedElements(master, elements);

			for (auto element : elements) {
			UInt nb_nodes_per_element = mesh.getNbNodesPerElement(element.type);
			Matrix<Real> elem_coords(spatial_dimension, nb_nodes_per_element);
			this->coordinatesOfElement(element, elem_coords);

			elem_size = FEEngine::getElementInradius(elem_coords, element.type);
			max_elem_size = std::max(max_elem_size, elem_size);
			min_elem_size = std::min(min_elem_size, elem_size);
			}
			}

			AKANTU_DEBUG_INFO("The maximum element size : " << max_elem_size);

			this->min_dd = min_elem_size;
			this->max_dd = max_elem_size;
			this->max_bb = max_elem_size;

			AKANTU_DEBUG_OUT();
			}

			/* -------------------------------------------------------------------------- */
			inline Vector<UInt>
			ContactDetector::constructConnectivity(UInt & slave, const Element & master) {

			Vector<UInt> master_conn =
			const_cast<const Mesh &>(this->mesh).getConnectivity(master);

			Vector<UInt> elem_conn(master_conn.size() + 1);

			elem_conn[0] = slave;
			for (UInt i = 1; i < elem_conn.size(); ++i) {
			elem_conn[i] = master_conn[i - 1];
			}

			return elem_conn;
			}

			/* -------------------------------------------------------------------------- */
			inline void ContactDetector::computeNormalOnElement(const Element & element,
			Vector<Real> & normal) {

			Matrix<Real> vectors(spatial_dimension, spatial_dimension - 1);
			this->vectorsAlongElement(element, vectors);

			switch (this->spatial_dimension) {
			case 2: {
			Math::normal2(vectors.storage(), normal.storage());
			break;
			}
			case 3: {
			Math::normal3(vectors(0).storage(), vectors(1).storage(), normal.storage());
			break;
			}
			default: { AKANTU_ERROR("Unknown dimension : " << spatial_dimension); }
			}

			// to ensure that normal is always outwards from master surface
			const auto & element_to_subelement =
			mesh.getElementToSubelement(element.type)(element.element);

			Vector<Real> outside(spatial_dimension);
			mesh.getBarycenter(element, outside);

			// check if mesh facets exists for cohesive elements contact
			Vector<Real> inside(spatial_dimension);
			if (mesh.isMeshFacets()) {
			mesh.getMeshParent().getBarycenter(element_to_subelement[0], inside);
			} else {
			mesh.getBarycenter(element_to_subelement[0], inside);
			}

			Vector<Real> inside_to_outside = outside - inside;
			auto projection = inside_to_outside.dot(normal);

			if (projection < 0) {
			normal *= -1.0;
			}
			}

			/* -------------------------------------------------------------------------- */
			inline void ContactDetector::vectorsAlongElement(const Element & el,
			Matrix<Real> & vectors) {

			UInt nb_nodes_per_element = Mesh::getNbNodesPerElement(el.type);

			Matrix<Real> coords(spatial_dimension, nb_nodes_per_element);
			this->coordinatesOfElement(el, coords);

			switch (spatial_dimension) {
			case 2: {
			vectors(0) = Vector<Real>(coords(1)) - Vector<Real>(coords(0));
			break;
			}
			case 3: {
			vectors(0) = Vector<Real>(coords(1)) - Vector<Real>(coords(0));
			vectors(1) = Vector<Real>(coords(2)) - Vector<Real>(coords(0));
			break;
			}
			default: { AKANTU_ERROR("Unknown dimension : " << spatial_dimension); }
			}
			}

			/* -------------------------------------------------------------------------- */
			inline Real ContactDetector::computeGap(Vector<Real> & slave,
			Vector<Real> & master) {

			Vector<Real> slave_to_master(spatial_dimension);
			slave_to_master = master - slave;

			Real gap = slave_to_master.norm();
			return gap;
			}

			/* -------------------------------------------------------------------------- */
			inline void
			ContactDetector::filterBoundaryElements(Array<Element> & elements,
			Array<Element> & boundary_elements) {

			for (auto elem : elements) {

			const auto & element_to_subelement =
			mesh.getElementToSubelement(elem.type)(elem.element);

			// for regular boundary elements
			if (element_to_subelement.size() == 1 and
			element_to_subelement[0].kind() == _ek_regular) {
			boundary_elements.push_back(elem);
			continue;
			}

			// for cohesive boundary elements
			UInt nb_subelements_regular = 0;
			for (auto subelem : element_to_subelement) {
			if (subelem == ElementNull)
			continue;

			if (subelem.kind() == _ek_regular)
			++nb_subelements_regular;
			}

			auto nb_subelements = element_to_subelement.size();

			if (nb_subelements_regular < nb_subelements)
			boundary_elements.push_back(elem);
			}
			}

			/* -------------------------------------------------------------------------- */
			/*inline bool
			ContactDetector::checkValidityOfSelfContact(const UInt & slave_node,
			ContactElement & element) {

			UInt master_node;

			for (auto & pair : contact_pairs) {
			if (pair.first == slave_node) {
			master_node = pair.second;
			break;
			}
			}

			Array<Element> elements;
			this->mesh.getAssociatedElements(slave_node, elements);

			Vector<Real> slave_normal(spatial_dimension);
			for (auto & elem : elements) {
			if (elem.kind() != _ek_regular)
			continue;

			Vector<UInt> connectivity =
			const_cast<const Mesh &>(this->mesh).getConnectivity(elem);

			Vector<Real> normal(spatial_dimension);
			this->computeNormalOnElement(elem, normal);

			slave_normal = slave_normal + normal;

			auto node_iter =
			std::find(connectivity.begin(), connectivity.end(), master_node);
			if (node_iter != connectivity.end()) {
			return false;
			}


			}

			if (std::abs(element.gap) > 2.0 * min_dd) {
			return false;
			}

			auto norm = slave_normal.norm();
			if (norm != 0) {
			slave_normal /= norm;
			}

			auto product = slave_normal.dot(element.normal);
			if (product >= 0) {
			return false;
			}

			return true;
			}*/



			/* -------------------------------------------------------------------------- */
			inline bool
			ContactDetector::isValidSelfContact(const UInt & slave_node, const Real & gap,
			const Vector<Real> & normal) {

			UInt master_node;

			// finding the master node corresponding to slave node
			for (auto & pair : contact_pairs) {
			if (pair.first == slave_node) {
			master_node = pair.second;
			break;
			}
			}

			Array<Element> slave_elements;
			this->mesh.getAssociatedElements(slave_node, slave_elements);

			// Check 1 : master node is not connected to elements connected to
			// slave node
			Vector<Real> slave_normal(spatial_dimension);
			for (auto & element : slave_elements) {
			if (element.kind() != _ek_regular)
			continue;

			Vector<UInt> connectivity =
			const_cast<const Mesh &>(this->mesh).getConnectivity(element);

			// finding the normal at slave node by averaging of normals
			Vector<Real> normal(spatial_dimension);
			GeometryUtils::normal(mesh, positions, element, normal);
			slave_normal = slave_normal + normal;

			auto node_iter =
			std::find(connectivity.begin(), connectivity.end(), master_node);
			if (node_iter != connectivity.end())
			return false;
			}

			// Check 2 : if gap is twice the size of smallest element
			if (std::abs(gap) > 2.0 * min_dd)
			return false;

			// Check 3 : check the directions of normal at slave node and at
			// master element, should be in opposite directions
			auto norm = slave_normal.norm();
			if (norm != 0)
			slave_normal /= norm;

			auto product = slave_normal.dot(normal);
			if (product >= 0)
			return false;

			return true;
			}


			} // namespace akantu

			#endif /* __AKANTU_CONTACT_DETECTOR_INLINE_IMPL_CC__ */

rAKA/src/model/contact_mechanics/contact_detector_inline_impl.cc846e29973f06features/contact

contact_detector_inline_impl.ccView Options

rAKA/src/model/contact_mechanics/contact_detector_inline_impl.cc
846e29973f06features/contact

contact_detector_inline_impl.cc
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