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structural_simulation_class.cpp
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executable file
·1009 lines (908 loc) · 37.9 KB
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/**
* @file structural_simulation_class.cpp
* @brief The structural simulation module is licensed under the Aladdin Free Public License (https://spdx.org/licenses/Aladdin.html) regarding usage for medical device development.
* Commercial use for medical device development is not permitted. This does not apply to applications in other fields.
* @details solid structural simulation class for general structural simulations
* @author Bence Z. Rochlitz - Virtonomy GmbH, Xiangyu Hu
*/
#include "structural_simulation_class.h"
////////////////////////////////////////////////////
/* global functions in StructuralSimulation */
////////////////////////////////////////////////////
BodyPartFromMesh::BodyPartFromMesh(SPHBody &body, SharedPtr<TriangleMeshShape> triangle_mesh_shape_ptr)
: BodyRegionByParticle(body, triangle_mesh_shape_ptr)
{
}
SolidBodyFromMesh::SolidBodyFromMesh(
SPHSystem &system, SharedPtr<TriangleMeshShape> triangle_mesh_shape, Real resolution,
SharedPtr<SaintVenantKirchhoffSolid> material_model, Vecd *pos_0, Real *volume)
: SolidBody(system, triangle_mesh_shape)
{
defineAdaptationRatios(1.15, system.GlobalResolution() / resolution);
defineBodyLevelSetShape().cleanLevelSet();
defineMaterial<SaintVenantKirchhoffSolid>(*material_model.get());
generateParticles<BaseParticles, Lattice>();
}
SolidBodyForSimulation::SolidBodyForSimulation(
SPHSystem &system, SharedPtr<TriangleMeshShape> triangle_mesh_shape, Real resolution,
Real physical_viscosity, SharedPtr<SaintVenantKirchhoffSolid> material_model, Vecd *pos_0, Real *volume)
: solid_body_from_mesh_(system, triangle_mesh_shape, resolution, material_model, pos_0, volume),
inner_body_relation_(solid_body_from_mesh_),
initial_normal_direction_(SimpleDynamics<NormalDirectionFromBodyShape>(solid_body_from_mesh_)),
correct_configuration_(inner_body_relation_),
stress_relaxation_first_half_(inner_body_relation_),
stress_relaxation_second_half_(inner_body_relation_),
damping_random_(0.2, inner_body_relation_, "Velocity", physical_viscosity)
{
initial_normal_direction_.exec();
std::cout << " normal initialization done" << std::endl;
}
BoundingBoxd expandBoundingBox(const BoundingBoxd &original, const BoundingBoxd &additional)
{
BoundingBoxd expanded = original;
for (int i = 0; i < expanded.lower_.size(); i++)
{
if (additional.lower_[i] < expanded.lower_[i])
{
expanded.lower_[i] = additional.lower_[i];
}
if (additional.upper_[i] > expanded.upper_[i])
{
expanded.upper_[i] = additional.upper_[i];
}
}
return expanded;
}
void relaxParticlesSingleResolution(bool write_particle_relaxation_data,
SolidBody &solid_body_from_mesh,
InnerRelation &solid_body_from_mesh_inner)
{
BodyStatesRecordingToVtp write_solid_body_from_mesh_to_vtp(solid_body_from_mesh);
//----------------------------------------------------------------------
// Methods used for particle relaxation.
//----------------------------------------------------------------------
SimpleDynamics<relax_dynamics::RandomizeParticlePosition> random_solid_body_from_mesh_particles(solid_body_from_mesh);
/** A Physics relaxation step. */
relax_dynamics::RelaxationStepLevelSetCorrectionInner relaxation_step_inner(solid_body_from_mesh_inner);
//----------------------------------------------------------------------
// Particle relaxation starts here.
//----------------------------------------------------------------------
random_solid_body_from_mesh_particles.exec(0.25);
relaxation_step_inner.SurfaceBounding().exec();
if (write_particle_relaxation_data)
{
write_solid_body_from_mesh_to_vtp.writeToFile(0.0);
}
solid_body_from_mesh.updateCellLinkedList();
//----------------------------------------------------------------------
// Particle relaxation time stepping start here.
//----------------------------------------------------------------------
int ite_p = 0;
while (ite_p < 1000)
{
relaxation_step_inner.exec();
ite_p += 1;
if (ite_p % 100 == 0)
{
std::cout << std::fixed << std::setprecision(9) << "Relaxation steps for the imported model N = " << ite_p << "\n";
if (write_particle_relaxation_data)
{
write_solid_body_from_mesh_to_vtp.writeToFile(ite_p);
}
}
}
std::cout << "The physics relaxation process of the imported model finished !" << std::endl;
}
std::tuple<Vecd *, Real *> generateAndRelaxParticlesFromMesh(
SharedPtr<TriangleMeshShape> triangle_mesh_shape, Real resolution, bool particle_relaxation, bool write_particle_relaxation_data)
{
BoundingBoxd bb = triangle_mesh_shape->getBounds();
SPHSystem system(bb, resolution);
SolidBody model(system, triangle_mesh_shape);
model.defineBodyLevelSetShape().cleanLevelSet();
model.defineMaterial<Solid>();
model.generateParticles<BaseParticles, Lattice>();
if (particle_relaxation)
{
InnerRelation inner_relation(model);
relaxParticlesSingleResolution(write_particle_relaxation_data, model, inner_relation);
}
return std::tuple<Vecd *, Real *>(model.getBaseParticles().ParticlePositions(), model.getBaseParticles().VolumetricMeasures());
}
BodyPartByParticle *createBodyPartFromMesh(SPHBody &body, const StlList &stl_list, size_t body_index, SharedPtr<TriangleMeshShape> tmesh)
{
#ifdef __EMSCRIPTEN__
tmesh->setName(stl_list[body_index].name);
return new BodyPartFromMesh(body, tmesh);
#else
tmesh->setName(stl_list[body_index]);
return new BodyPartFromMesh(body, tmesh);
#endif
}
StructuralSimulationInput::StructuralSimulationInput(
std::string relative_input_path,
StlList imported_stl_list,
Real scale_stl,
StdVec<Vec3d> translation_list,
StdVec<Real> resolution_list,
StdVec<SharedPtr<SaintVenantKirchhoffSolid>> material_model_list,
StdVec<Real> physical_viscosity,
StdVec<IndexVector> contacting_bodies_list)
: relative_input_path_(relative_input_path),
imported_stl_list_(imported_stl_list),
scale_stl_(scale_stl),
translation_list_(translation_list),
resolution_list_(resolution_list),
material_model_list_(material_model_list),
physical_viscosity_(physical_viscosity),
contacting_body_pairs_list_(contacting_bodies_list),
time_dep_contacting_body_pairs_list_({}),
particle_relaxation_list_({})
{
for (size_t i = 0; i < resolution_list_.size(); i++)
{
particle_relaxation_list_.push_back(true);
}
write_particle_relaxation_data_ = false;
// scale system boundaries
scale_system_boundaries_ = 1;
// boundary conditions
non_zero_gravity_ = {};
force_bounding_box_tuple_ = {};
force_in_body_region_tuple_ = {};
surface_pressure_tuple_ = {};
spring_damper_tuple_ = {};
surface_spring_tuple_ = {};
body_indices_fixed_constraint_ = {};
body_indices_fixed_constraint_region_ = {};
position_solid_body_tuple_ = {};
position_scale_solid_body_tuple_ = {};
translation_solid_body_tuple_ = {};
translation_solid_body_part_tuple_ = {};
};
///////////////////////////////////////
/* StructuralSimulation members */
///////////////////////////////////////
StructuralSimulation::StructuralSimulation(const StructuralSimulationInput &input)
: // generic input
relative_input_path_(input.relative_input_path_),
imported_stl_list_(input.imported_stl_list_),
scale_stl_(input.scale_stl_),
translation_list_(input.translation_list_),
resolution_list_(input.resolution_list_),
material_model_list_(input.material_model_list_),
physical_viscosity_(input.physical_viscosity_),
contacting_body_pairs_list_(input.contacting_body_pairs_list_),
time_dep_contacting_body_pairs_list_(input.time_dep_contacting_body_pairs_list_),
// default system, optional: particle relaxation, scale_system_boundaries
particle_relaxation_list_(input.particle_relaxation_list_),
write_particle_relaxation_data_(input.write_particle_relaxation_data_),
system_resolution_(Eps),
system_(SPHSystem(BoundingBoxd(Vec3d::Constant(-Eps), Vec3d::Constant(Eps)), system_resolution_)),
scale_system_boundaries_(input.scale_system_boundaries_),
physical_time_(*system_.getSystemVariableDataByName<Real>("PhysicalTime")),
// optional: boundary conditions
non_zero_gravity_(input.non_zero_gravity_),
force_bounding_box_tuple_(input.force_bounding_box_tuple_),
force_in_body_region_tuple_(input.force_in_body_region_tuple_),
surface_pressure_tuple_(input.surface_pressure_tuple_),
spring_damper_tuple_(input.spring_damper_tuple_),
surface_spring_tuple_(input.surface_spring_tuple_),
body_indices_fixed_constraint_(input.body_indices_fixed_constraint_),
body_indices_fixed_constraint_region_(input.body_indices_fixed_constraint_region_),
position_solid_body_tuple_(input.position_solid_body_tuple_),
position_scale_solid_body_tuple_(input.position_scale_solid_body_tuple_),
translation_solid_body_tuple_(input.translation_solid_body_tuple_),
translation_solid_body_part_tuple_(input.translation_solid_body_part_tuple_),
// iterators
iteration_(0)
{
// scaling of translation and resolution
scaleTranslationAndResolution();
// set the default resolution to the max in the resolution list
setSystemResolutionMax();
// create the body mesh list for triangular mesh shapes storage
createBodyMeshList();
// set up the system
calculateSystemBoundaries();
system_.setRunParticleRelaxation(true);
// initialize solid bodies with their properties
initializeElasticSolidBodies();
// contacts
initializeAllContacts();
// boundary conditions
initializeGravity();
initializeExternalForceInBoundingBox();
initializeForceInBodyRegion();
initializeSurfacePressure();
initializeSpringDamperConstraintParticleWise();
initializeSpringNormalOnSurfaceParticles();
initializeConstrainSolidBody();
initializeConstrainSolidBodyRegion();
initializePositionSolidBody();
initializePositionScaleSolidBody();
initializeTranslateSolidBody();
initializeTranslateSolidBodyPart();
// initialize simulation
initializeSimulation();
}
StructuralSimulation::~StructuralSimulation()
{
}
void StructuralSimulation::scaleTranslationAndResolution()
{
// scale the translation_list_, system_resolution_ and resolution_list_
for (size_t i = 0; i < translation_list_.size(); i++)
{
translation_list_[i] *= scale_stl_;
}
system_resolution_ *= scale_stl_;
for (size_t i = 0; i < resolution_list_.size(); i++)
{
resolution_list_[i] *= scale_stl_;
}
}
void StructuralSimulation::setSystemResolutionMax()
{
system_resolution_ = 0.0;
for (size_t i = 0; i < resolution_list_.size(); i++)
{
if (system_resolution_ < resolution_list_[i])
{
system_resolution_ = resolution_list_[i];
}
}
system_.setGlobalResolution(system_resolution_);
}
void StructuralSimulation::calculateSystemBoundaries()
{
// calculate system bounds from all bodies
for (size_t i = 0; i < body_mesh_list_.size(); i++)
{
BoundingBoxd additional = body_mesh_list_[i]->getBounds();
system_.setSystemDomainBounds(expandBoundingBox(system_.getSystemDomainBounds(), additional));
}
// scale the system bounds around the center point
Vecd center_point = (system_.getSystemDomainBounds().lower_ + system_.getSystemDomainBounds().upper_) * 0.5;
Vecd distance_first = system_.getSystemDomainBounds().lower_ - center_point;
Vecd distance_second = system_.getSystemDomainBounds().upper_ - center_point;
system_.getSystemDomainBounds().lower_ = center_point + distance_first * scale_system_boundaries_;
system_.getSystemDomainBounds().upper_ = center_point + distance_second * scale_system_boundaries_;
}
void StructuralSimulation::createBodyMeshList()
{
body_mesh_list_ = {};
for (size_t i = 0; i < imported_stl_list_.size(); i++)
{
std::string relative_input_path_copy = relative_input_path_;
#ifdef __EMSCRIPTEN__
body_mesh_list_.push_back(makeShared<TriangleMeshShapeSTL>(reinterpret_cast<const uint8_t *>(imported_stl_list_[i].ptr), translation_list_[i], scale_stl_, imported_stl_list_[i].name));
#else
body_mesh_list_.push_back(makeShared<TriangleMeshShapeSTL>(relative_input_path_copy.append(imported_stl_list_[i]), translation_list_[i], scale_stl_, imported_stl_list_[i]));
#endif
}
}
void StructuralSimulation::initializeElasticSolidBodies()
{
solid_body_list_ = {};
particle_normal_update_ = {};
for (size_t i = 0; i < body_mesh_list_.size(); i++)
{
std::string temp_name = "";
#ifdef __EMSCRIPTEN__
temp_name.append(imported_stl_list_[i].name);
#else // __EMSCRIPTEN__
temp_name.append(imported_stl_list_[i]);
#endif // __EMSCRIPTEN__
// we delete the .stl ending
temp_name.erase(temp_name.size() - 4);
// create the initial particles from the triangle mesh shape with particle relaxation option
std::tuple<Vecd *, Real *> particles =
generateAndRelaxParticlesFromMesh(body_mesh_list_[i], resolution_list_[i], particle_relaxation_list_[i], write_particle_relaxation_data_);
// get the particles' initial position and their volume
Vecd *pos_0 = std::get<0>(particles);
Real *volume = std::get<1>(particles);
// create the SolidBodyForSimulation
solid_body_list_.emplace_back(makeShared<SolidBodyForSimulation>(
system_, body_mesh_list_[i], resolution_list_[i], physical_viscosity_[i], material_model_list_[i], pos_0, volume));
// update normal direction of particles
particle_normal_update_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::UpdateElasticNormalDirection>>(*solid_body_list_[i]->getSolidBodyFromMesh()));
}
}
void StructuralSimulation::initializeContactBetweenTwoBodies(int first, int second)
{
SolidBodyFromMesh *first_body = solid_body_list_[first]->getSolidBodyFromMesh();
SolidBodyFromMesh *second_body = solid_body_list_[second]->getSolidBodyFromMesh();
contact_list_.emplace_back(makeShared<SurfaceContactRelation>(*first_body, RealBodyVector({second_body})));
contact_list_.emplace_back(makeShared<SurfaceContactRelation>(*second_body, RealBodyVector({first_body})));
int last = contact_list_.size() - 1;
contact_density_list_.push_back(makeShared<InteractionDynamics<solid_dynamics::ContactFactorSummation>>(*contact_list_[last - 1]));
contact_density_list_.push_back(makeShared<InteractionDynamics<solid_dynamics::ContactFactorSummation>>(*contact_list_[last]));
contact_force_list_.push_back(makeShared<InteractionWithUpdate<solid_dynamics::ContactForce>>(*contact_list_[last - 1]));
contact_force_list_.push_back(makeShared<InteractionWithUpdate<solid_dynamics::ContactForce>>(*contact_list_[last]));
}
void StructuralSimulation::initializeAllContacts()
{
contact_list_ = {};
contact_density_list_ = {};
contact_force_list_ = {};
// first place all the regular contacts into the lists
for (size_t i = 0; i < contacting_body_pairs_list_.size(); i++)
{
SolidBodyFromMesh *contact_body = solid_body_list_[i]->getSolidBodyFromMesh();
RealBodyVector target_list = {};
for (size_t target_i : contacting_body_pairs_list_[i])
{
target_list.emplace_back(solid_body_list_[target_i]->getSolidBodyFromMesh());
}
contact_list_.emplace_back(makeShared<SurfaceContactRelation>(*contact_body, target_list));
int last = contact_list_.size() - 1;
contact_density_list_.emplace_back(makeShared<InteractionDynamics<solid_dynamics::ContactFactorSummation>>(*contact_list_[last]));
contact_force_list_.emplace_back(makeShared<InteractionWithUpdate<solid_dynamics::ContactForce>>(*contact_list_[last]));
}
// continue appending the lists with the time dependent contacts
for (size_t i = 0; i < time_dep_contacting_body_pairs_list_.size(); i++)
{
int body_1 = time_dep_contacting_body_pairs_list_[i].first[0];
int body_2 = time_dep_contacting_body_pairs_list_[i].first[1];
initializeContactBetweenTwoBodies(body_1, body_2); // vector with first element being array with indices
}
}
void StructuralSimulation::initializeGravity()
{
// collect all the body indices with non-zero gravity
StdVec<int> gravity_indices = {};
for (size_t i = 0; i < non_zero_gravity_.size(); i++)
{
gravity_indices.push_back(non_zero_gravity_[i].first);
}
// initialize gravity
initialize_gravity_ = {};
size_t gravity_index_i = 0; // iterating through gravity_indices
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
// check if i is in indices_gravity
if (count(gravity_indices.begin(), gravity_indices.end(), i))
{
SharedPtr<Gravity> gravity_ptr = makeShared<Gravity>(non_zero_gravity_[gravity_index_i].second);
gravity_list_.emplace_back(non_zero_gravity_[gravity_index_i].second);
initialize_gravity_.emplace_back(makeShared<SimpleDynamics<GravityForce<Gravity>>>(
*solid_body_list_[i]->getSolidBodyFromMesh(), gravity_list_.back()));
gravity_index_i++;
}
}
}
void StructuralSimulation::initializeExternalForceInBoundingBox()
{
force_bounding_box_ = {};
for (size_t i = 0; i < force_bounding_box_tuple_.size(); i++)
{
SolidBody *solid_body = solid_body_list_[std::get<0>(force_bounding_box_tuple_[i])]->getSolidBodyFromMesh();
force_bounding_box_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::ExternalForceInBoundingBox>>(
*solid_body, std::get<1>(force_bounding_box_tuple_[i]), std::get<2>(force_bounding_box_tuple_[i])));
}
}
void StructuralSimulation::initializeForceInBodyRegion()
{
force_in_body_region_ = {};
for (size_t i = 0; i < force_in_body_region_tuple_.size(); i++)
{
int body_index = std::get<0>(force_in_body_region_tuple_[i]);
BoundingBoxd bbox = std::get<1>(force_in_body_region_tuple_[i]);
Vec3d force = std::get<2>(force_in_body_region_tuple_[i]);
Real end_time = std::get<3>(force_in_body_region_tuple_[i]);
// get the length of each side to create the box
Real x_side = bbox.upper_[0] - bbox.lower_[0];
Real y_side = bbox.upper_[1] - bbox.lower_[1];
Real z_side = bbox.upper_[2] - bbox.lower_[2];
Vec3d halfsize_bbox(0.5 * x_side, 0.5 * y_side, 0.5 * z_side);
// get the center point for translation from the origin
Vec3d center = (bbox.upper_ + bbox.lower_) * 0.5;
// SimTK geometric modeling resolution
int resolution(20);
// create the triangle mesh of the box
BodyPartFromMesh *bp = body_part_tri_mesh_keeper_.createPtr<BodyPartFromMesh>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(), makeShared<TriangleMeshShapeBrick>(halfsize_bbox, resolution, center, imported_stl_list_[body_index]));
force_in_body_region_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::ForceInBodyRegion>>(*bp, force, end_time));
}
}
void StructuralSimulation::initializeSurfacePressure()
{
surface_pressure_ = {};
for (size_t i = 0; i < surface_pressure_tuple_.size(); i++)
{
int body_index = std::get<0>(surface_pressure_tuple_[i]);
SharedPtr<TriangleMeshShape> tri_mesh = std::get<1>(surface_pressure_tuple_[i]);
Vec3d point = std::get<2>(surface_pressure_tuple_[i]);
StdVec<std::array<Real, 2>> pressure_over_time = std::get<3>(surface_pressure_tuple_[i]);
BodyPartByParticle *bp = body_part_tri_mesh_keeper_.createPtr<BodyPartFromMesh>(*solid_body_list_[body_index]->getSolidBodyFromMesh(), tri_mesh);
surface_pressure_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::SurfacePressureFromSource>>(*bp, point, pressure_over_time));
}
}
void StructuralSimulation::initializeSpringDamperConstraintParticleWise()
{
spring_damper_constraint_ = {};
for (size_t i = 0; i < spring_damper_tuple_.size(); i++)
{
SolidBody *solid_body = solid_body_list_[std::get<0>(spring_damper_tuple_[i])]->getSolidBodyFromMesh();
spring_damper_constraint_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::SpringDamperConstraintParticleWise>>(
*solid_body, std::get<1>(spring_damper_tuple_[i]), std::get<2>(spring_damper_tuple_[i])));
}
}
void StructuralSimulation::initializeSpringNormalOnSurfaceParticles()
{
surface_spring_ = {};
for (size_t i = 0; i < surface_spring_tuple_.size(); i++)
{
int body_index = std::get<0>(surface_spring_tuple_[i]);
SharedPtr<TriangleMeshShape> tri_mesh = std::get<1>(surface_spring_tuple_[i]);
bool inner_outer = std::get<2>(surface_spring_tuple_[i]);
Vec3d point = std::get<3>(surface_spring_tuple_[i]);
Real spring_stiffness = std::get<4>(surface_spring_tuple_[i]);
Real damping_coefficient = std::get<5>(surface_spring_tuple_[i]);
surface_spring_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::SpringNormalOnSurfaceParticles>>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(),
inner_outer, point, spring_stiffness, damping_coefficient));
}
}
void StructuralSimulation::initializeConstrainSolidBody()
{
fixed_constraint_body_ = {};
for (size_t i = 0; i < body_indices_fixed_constraint_.size(); i++)
{
int body_index = body_indices_fixed_constraint_[i];
fixed_constraint_body_.emplace_back(makeShared<SimpleDynamics<FixBodyConstraint>>(*solid_body_list_[body_index]->getSolidBodyFromMesh()));
}
}
void StructuralSimulation::initializeConstrainSolidBodyRegion()
{
fixed_constraint_region_ = {};
for (size_t i = 0; i < body_indices_fixed_constraint_region_.size(); i++)
{
int body_index = body_indices_fixed_constraint_region_[i].first;
BoundingBoxd bbox = body_indices_fixed_constraint_region_[i].second;
// get the length of each side to create the box
Real x_side = bbox.upper_[0] - bbox.lower_[0];
Real y_side = bbox.upper_[1] - bbox.lower_[1];
Real z_side = bbox.upper_[2] - bbox.lower_[2];
Vec3d halfsize_bbox(0.5 * x_side, 0.5 * y_side, 0.5 * z_side);
// get the center point for translation from the origin
Vec3d center = (bbox.upper_ + bbox.lower_) * 0.5;
// SimTK geometric modeling resolution
int resolution(20);
// create the triangle mesh of the box
BodyPartFromMesh *bp = body_part_tri_mesh_keeper_.createPtr<BodyPartFromMesh>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(), makeShared<TriangleMeshShapeBrick>(halfsize_bbox, resolution, center, imported_stl_list_[body_index]));
fixed_constraint_region_.emplace_back(makeShared<SimpleDynamics<FixBodyPartConstraint>>(*bp));
}
}
void StructuralSimulation::initializePositionSolidBody()
{
position_solid_body_ = {};
for (size_t i = 0; i < position_solid_body_tuple_.size(); i++)
{
int body_index = std::get<0>(position_solid_body_tuple_[i]);
Real start_time = std::get<1>(position_solid_body_tuple_[i]);
Real end_time = std::get<2>(position_solid_body_tuple_[i]);
Vecd pos_end_center = std::get<3>(position_solid_body_tuple_[i]);
position_solid_body_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::PositionSolidBody>>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(), start_time, end_time, pos_end_center));
}
}
void StructuralSimulation::initializePositionScaleSolidBody()
{
position_scale_solid_body_ = {};
for (size_t i = 0; i < position_scale_solid_body_tuple_.size(); i++)
{
int body_index = std::get<0>(position_scale_solid_body_tuple_[i]);
Real start_time = std::get<1>(position_scale_solid_body_tuple_[i]);
Real end_time = std::get<2>(position_scale_solid_body_tuple_[i]);
Real scale = std::get<3>(position_scale_solid_body_tuple_[i]);
position_scale_solid_body_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::PositionScaleSolidBody>>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(), start_time, end_time, scale));
}
}
void StructuralSimulation::initializeTranslateSolidBody()
{
translation_solid_body_ = {};
for (size_t i = 0; i < translation_solid_body_tuple_.size(); i++)
{
int body_index = std::get<0>(translation_solid_body_tuple_[i]);
Real start_time = std::get<1>(translation_solid_body_tuple_[i]);
Real end_time = std::get<2>(translation_solid_body_tuple_[i]);
Vecd translation = std::get<3>(translation_solid_body_tuple_[i]);
translation_solid_body_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::TranslateSolidBody>>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(), start_time, end_time, translation));
}
}
void StructuralSimulation::initializeTranslateSolidBodyPart()
{
translation_solid_body_part_ = {};
for (size_t i = 0; i < translation_solid_body_part_tuple_.size(); i++)
{
int body_index = std::get<0>(translation_solid_body_part_tuple_[i]);
Real start_time = std::get<1>(translation_solid_body_part_tuple_[i]);
Real end_time = std::get<2>(translation_solid_body_part_tuple_[i]);
Vecd translation = std::get<3>(translation_solid_body_part_tuple_[i]);
BodyPartFromMesh *bp = body_part_tri_mesh_keeper_.createPtr<BodyPartFromMesh>(
*solid_body_list_[body_index]->getSolidBodyFromMesh(), body_mesh_list_[body_index]);
translation_solid_body_part_.emplace_back(makeShared<SimpleDynamics<solid_dynamics::TranslateSolidBodyPart>>(
*bp, start_time, end_time, translation));
}
}
void StructuralSimulation::executeInitialNormalDirection()
{
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
solid_body_list_[i]->getInitialNormalDirection()->exec();
}
}
void StructuralSimulation::executeCorrectConfiguration()
{
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
solid_body_list_[i]->getCorrectConfiguration()->exec();
}
}
void StructuralSimulation::executeUpdateElasticNormalDirection()
{
for (size_t i = 0; i < particle_normal_update_.size(); i++)
{
particle_normal_update_[i]->exec();
}
}
void StructuralSimulation::executeInitializeGravity()
{
for (size_t i = 0; i < initialize_gravity_.size(); i++)
{
initialize_gravity_[i]->exec();
}
}
void StructuralSimulation::executeExternalForceInBoundingBox()
{
for (size_t i = 0; i < force_bounding_box_.size(); i++)
{
force_bounding_box_[i]->exec();
}
}
void StructuralSimulation::executeForceInBodyRegion()
{
for (size_t i = 0; i < force_in_body_region_.size(); i++)
{
force_in_body_region_[i]->exec();
}
}
void StructuralSimulation::executeSurfacePressure()
{
for (size_t i = 0; i < surface_pressure_.size(); i++)
{
surface_pressure_[i]->exec();
}
}
void StructuralSimulation::executeSpringDamperConstraintParticleWise()
{
for (size_t i = 0; i < spring_damper_constraint_.size(); i++)
{
spring_damper_constraint_[i]->exec();
}
}
void StructuralSimulation::executeSpringNormalOnSurfaceParticles()
{
for (size_t i = 0; i < surface_spring_.size(); i++)
{
surface_spring_[i]->exec();
}
}
void StructuralSimulation::executeContactFactorSummation()
{
// number of contacts that are not time dependent: contact pairs * 2
size_t number_of_general_contacts = contacting_body_pairs_list_.size();
for (size_t i = 0; i < contact_density_list_.size(); i++)
{
if (i < number_of_general_contacts)
{
contact_density_list_[i]->exec();
}
else
{
// index of the time dependent contact body pair
// for i = 0, 1 --> index = 0, i = 2, 3 --> index = 1, and so on..
int index = (i - number_of_general_contacts) / 2;
Real start_time = time_dep_contacting_body_pairs_list_[index].second[0];
Real end_time = time_dep_contacting_body_pairs_list_[index].second[1];
if (physical_time_ >= start_time && physical_time_ <= end_time)
{
contact_density_list_[i]->exec();
}
}
}
}
void StructuralSimulation::executeContactForce()
{
// number of contacts that are not time dependent: contact pairs * 2
size_t number_of_general_contacts = contacting_body_pairs_list_.size();
for (size_t i = 0; i < contact_force_list_.size(); i++)
{
if (i < number_of_general_contacts)
{
contact_force_list_[i]->exec();
}
else
{
// index of the time dependent contact body pair
// for i = 0, 1 --> index = 0, i = 2, 3 --> index = 1, and so on..
int index = (i - number_of_general_contacts) / 2;
Real start_time = time_dep_contacting_body_pairs_list_[index].second[0];
Real end_time = time_dep_contacting_body_pairs_list_[index].second[1];
if (physical_time_ >= start_time && physical_time_ <= end_time)
{
contact_force_list_[i]->exec();
}
}
}
}
void StructuralSimulation::executeStressRelaxationFirstHalf(Real dt)
{
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
solid_body_list_[i]->getStressRelaxationFirstHalf()->exec(dt);
}
}
void StructuralSimulation::executeConstrainSolidBody()
{
for (size_t i = 0; i < fixed_constraint_body_.size(); i++)
{
fixed_constraint_body_[i]->exec();
}
}
void StructuralSimulation::executeConstrainSolidBodyRegion()
{
for (size_t i = 0; i < fixed_constraint_region_.size(); i++)
{
fixed_constraint_region_[i]->exec();
}
}
void StructuralSimulation::executePositionSolidBody(Real dt)
{
for (size_t i = 0; i < position_solid_body_.size(); i++)
{
position_solid_body_[i]->exec(dt);
}
}
void StructuralSimulation::executePositionScaleSolidBody(Real dt)
{
for (size_t i = 0; i < position_scale_solid_body_.size(); i++)
{
position_scale_solid_body_[i]->exec(dt);
}
}
void StructuralSimulation::executeTranslateSolidBody(Real dt)
{
for (size_t i = 0; i < translation_solid_body_.size(); i++)
{
translation_solid_body_[i]->exec(dt);
}
}
void StructuralSimulation::executeTranslateSolidBodyPart(Real dt)
{
for (size_t i = 0; i < translation_solid_body_part_.size(); i++)
{
translation_solid_body_part_[i]->exec(dt);
}
}
void StructuralSimulation::executeDamping(Real dt)
{
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
solid_body_list_[i]->getDampingWithRandomChoice()->exec(dt);
}
}
void StructuralSimulation::executeStressRelaxationSecondHalf(Real dt)
{
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
solid_body_list_[i]->getStressRelaxationSecondHalf()->exec(dt);
}
}
void StructuralSimulation::executeUpdateCellLinkedList()
{
for (size_t i = 0; i < solid_body_list_.size(); i++)
{
solid_body_list_[i]->getSolidBodyFromMesh()->updateCellLinkedList();
}
}
void StructuralSimulation::executeContactUpdateConfiguration()
{
// number of contacts that are not time dependent: contact pairs * 2
size_t number_of_general_contacts = contacting_body_pairs_list_.size();
for (size_t i = 0; i < contact_list_.size(); i++)
{
// general contacts = contacting_bodies * 2
if (i < number_of_general_contacts)
{
contact_list_[i]->updateConfiguration();
}
// time dependent contacts = time dep. contacting_bodies * 2
else
{
// index of the time dependent contact body pair
// for i = 0, 1 --> index = 0, i = 2, 3 --> index = 1, and so on..
int index = (i - number_of_general_contacts) / 2;
Real start_time = time_dep_contacting_body_pairs_list_[index].second[0];
Real end_time = time_dep_contacting_body_pairs_list_[index].second[1];
if (physical_time_ >= start_time && physical_time_ <= end_time)
{
contact_list_[i]->updateConfiguration();
}
}
}
}
void StructuralSimulation::initializeSimulation()
{
physical_time_ = 0.0;
/** INITIALIZE SYSTEM */
system_.initializeSystemCellLinkedLists();
system_.initializeSystemConfigurations();
/** INITIAL CONDITION */
executeCorrectConfiguration();
/** ACOUSTIC TIME STEP */
initializeAcousticTimeStepList();
}
void StructuralSimulation::initializeAcousticTimeStepList()
{
for (auto &body : solid_body_list_)
acoustic_time_step_list_.emplace_back(makeShared<ReduceDynamics<solid_dynamics::AcousticTimeStep>>(*body->getSolidBodyFromMesh()));
}
void StructuralSimulation::runSimulationStep(Real &dt, Real &integration_time)
{
if (iteration_ % 100 == 0)
std::cout << "N=" << iteration_ << " Time: " << physical_time_ << " dt: " << dt << "\n";
/** UPDATE NORMAL DIRECTIONS */
executeUpdateElasticNormalDirection();
/** ACTIVE BOUNDARY CONDITIONS */
// force (acceleration) based
executeInitializeGravity();
executeExternalForceInBoundingBox();
executeForceInBodyRegion();
executeSurfacePressure();
executeSpringDamperConstraintParticleWise();
executeSpringNormalOnSurfaceParticles();
/** CONTACT */
executeContactFactorSummation();
executeContactForce();
/** STRESS RELAXATION, DAMPING, POSITIONAL CONSTRAINTS */
executeStressRelaxationFirstHalf(dt);
executeConstrainSolidBody();
executeConstrainSolidBodyRegion();
executePositionSolidBody(dt);
executePositionScaleSolidBody(dt);
executeTranslateSolidBody(dt);
// velocity based
executeTranslateSolidBodyPart(dt);
executeDamping(dt);
executeConstrainSolidBody();
executeConstrainSolidBodyRegion();
executePositionSolidBody(dt);
executePositionScaleSolidBody(dt);
executeTranslateSolidBody(dt);
// velocity based
executeTranslateSolidBodyPart(dt);
executeStressRelaxationSecondHalf(dt);
/** UPDATE TIME STEP SIZE, INCREMENT */
iteration_++;
dt = getSmallestTimeStepAmongSolidBodies();
integration_time += dt;
physical_time_ += dt;
/** UPDATE BODIES CELL LINKED LISTS */
executeUpdateCellLinkedList();
/** UPDATE CONTACT CONFIGURATION */
executeContactUpdateConfiguration();
}
void StructuralSimulation::runSimulation(Real end_time)
{
BodyStatesRecordingToVtp write_states(system_);
/** Statistics for computing time. */
write_states.writeToFile(0);
Real output_period = end_time / 100.0;
Real dt = 0.0;
TickCount t1 = TickCount::now();
TimeInterval interval;
/** Main loop */
while (physical_time_ < end_time)
{
Real integration_time = 0.0;
while (integration_time < output_period)
{
runSimulationStep(dt, integration_time);
}
TickCount t2 = TickCount::now();
// write data to file
write_states.writeToFile();
TickCount t3 = TickCount::now();
interval += t3 - t2;
}
TickCount t4 = TickCount::now();
TimeInterval tt;
tt = t4 - t1 - interval;
std::cout << "Total wall time for computation: " << tt.seconds() << " seconds." << std::endl;
}
double StructuralSimulation::runSimulationFixedDurationJS(int number_of_steps)
{
BodyStatesRecordingToVtp write_states(system_);
physical_time_ = 0.0;
/** Statistics for computing time. */
write_states.writeToFile(0);
int output_period = 100;
Real dt = 0.0;
TickCount t1 = TickCount::now();
TimeInterval interval;
/** Main loop */
while (iteration_ < number_of_steps)
{
Real integration_time = 0.0;
int output_step = 0;
while (output_step < output_period)
{
runSimulationStep(dt, integration_time);
output_step++;
}
TickCount t2 = TickCount::now();
write_states.writeToFile();
TickCount t3 = TickCount::now();
interval += t3 - t2;
}
TickCount t4 = TickCount::now();
TimeInterval tt;
tt = t4 - t1 - interval;
return tt.seconds();
}
Real StructuralSimulation::getMaxDisplacement(int body_index)
{
BaseParticles *base_particles = solid_body_list_[body_index].get()->getElasticSolidParticles();
Vecd *pos = base_particles->ParticlePositions();
Vecd *pos0 = base_particles->registerStateVariableDataFrom<Vecd>("InitialPosition", "Position");
Real displ_max = 0;
for (size_t i = 0; i < base_particles->TotalRealParticles(); i++)
{
Real displ = (pos[i] - pos0[i]).norm();
if (displ > displ_max)
displ_max = displ;
}
return displ_max;
}
Real StructuralSimulation::getSmallestTimeStepAmongSolidBodies()
{
Real dt = MaxReal;
for (auto &acoustic_time_step : acoustic_time_step_list_)
dt = SMIN(dt, acoustic_time_step->exec());
return dt;
}
StructuralSimulationJS::StructuralSimulationJS(const StructuralSimulationInput &input)
: StructuralSimulation(input),
write_states_(system_),
dt(0.0)
{
write_states_.writeToFile(0);
physical_time_ = 0.0;
}
void StructuralSimulationJS::runSimulationFixedDuration(int number_of_steps)
{
/** Statistics for computing time. */
TickCount t_start = TickCount::now(); // computation time monitoring
/** Main loop */
for (int i = 0; i < number_of_steps; ++i)
{
Real integration_time = 0.0;
runSimulationStep(dt, integration_time);
}
TickCount t_end = TickCount::now(); // computation time monitoring
TimeInterval t_interval = t_end - t_start;
std::cout << "Total time for computation: " << t_interval.seconds() << " seconds." << std::endl;