[yupeng]

The error didn’t reappear anymore when I using SphereCollsionModelas the first template parameter in NeedleContact.cpp.

Creator<sofa::core::collision::Contact::Factory, NeedleContact<
	SphereCollisionModel<sofa::defaulttype::Vec3Types>, PointCollisionModel<sofa::defaulttype::Vec3Types>> > PointSphereNeedleContactClass("NeedleContact", true);
Creator<sofa::core::collision::Contact::Factory, NeedleContact<
	SphereCollisionModel<sofa::defaulttype::Vec3Types>, LineCollisionModel<sofa::defaulttype::Vec3Types>> > LineSphereNeedleContactClass("NeedleContact", true);

But the haptic force is too large and not stable.
LCPConstraintSolver.cpp Function nlcp_gaussseidel_unbuild spites out msg_error()<< " WARNING dim should be dividable by 3 in nlcp_gaussseidel"

[yupeng]

Dear @Hugo,
Thanks for your kind advice.

You said people didn’t use Tetra as a collision model, then how did they know which Tetra contains needle points? Is there a more convenient approach to do that?

@agnesenardi, I am also working on this simulation, maybe we could collaborate and see what we could do.

[yupeng]

Hi @Hugo,

Using the scene file you proposed, I could use the TetrahedronCollisionmodel now. But, when the haptic device (PointCollisionModel) contacts with liver, the program corrupt. I found it has a relation with the mapping method.

When detecting a collision, the Mapper for TetrahedronCollisionModel (derived from BarycentricContactMapper) would create a BarycentricMapperMeshTopology from TetrahedronCollisionModel’s topology which is nullptr.

// model->getCollisionTopology() is nullptr
mapper = sofa::core::objectmodel::New<mapping::BarycentricMapperMeshTopology<InDataTypes, typename BarycentricContactMapper::DataTypes> >(model->getCollisionTopology(), (topology::PointSetTopologyContainer*)nullptr);

//call stack is as bellow
SofaMiscCollision.dll!sofa::component::collision::BarycentricContactMapper<sofa::component::collision::TetrahedronCollisionModel,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::createMapping(const char * name) Line 74	C++

This topology would be used when function apply() called.
The debugging call stack is as follow:

SofaCore.dll!sofa::core::topology::BaseMeshTopology::getLines() Line 237	C++
SofaBaseMechanics.dll!sofa::component::mapping::BarycentricMapperMeshTopology<sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::apply(sofa::helper::vector<sofa::defaulttype::Vec<3,double>,sofa::helper::CPUMemoryManager<sofa::defaulttype::Vec<3,double>>> & out, const sofa::helper::vector<sofa::defaulttype::Vec<3,double>,sofa::helper::CPUMemoryManager<sofa::defaulttype::Vec<3,double>>> & in) Line 1027	C++
SofaBaseMechanics.dll!sofa::component::mapping::BarycentricMapping<sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::apply(const sofa::core::MechanicalParams * mparams, sofa::core::objectmodel::Data<sofa::helper::vector<sofa::defaulttype::Vec<3,double>,sofa::helper::CPUMemoryManager<sofa::defaulttype::Vec<3,double>>>> & out, const sofa::core::objectmodel::Data<sofa::helper::vector<sofa::defaulttype::Vec<3,double>,sofa::helper::CPUMemoryManager<sofa::defaulttype::Vec<3,double>>>> & in) Line 308	C++
SofaCore.dll!sofa::core::Mapping<sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::apply(const sofa::core::MechanicalParams * mparams, sofa::core::TMultiVecId<1,1> outPos, sofa::core::TMultiVecId<1,0> inPos) Line 157	C++
SofaMiscCollision.dll!sofa::component::collision::BarycentricContactMapper<sofa::component::collision::TetrahedronCollisionModel,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::update() Line 101	C++
SofaMiscCollision.dll!sofa::component::collision::FrictionContact<sofa::component::collision::TetrahedronCollisionModel,sofa::component::collision::PointCollisionModel<sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::activateMappers() Line 205	C++
SofaMiscCollision.dll!sofa::component::collision::FrictionContact<sofa::component::collision::TetrahedronCollisionModel,sofa::component::collision::PointCollisionModel<sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>,sofa::defaulttype::StdVectorTypes<sofa::defaulttype::Vec<3,double>,sofa::defaulttype::Vec<3,double>,double>>::createResponse(sofa::core::objectmodel::BaseContext * group) Line 215	C++
SofaBaseCollision.dll!sofa::component::collision::DefaultPipeline::doCollisionResponse() Line 260	C++
SofaSimulationCore.dll!sofa::simulation::PipelineImpl::computeCollisionResponse() Line 126	C++
[Inline Frame] SofaSimulationCore.dll!sofa::simulation::Visitor::for_each(sofa::simulation::CollisionVisitor *) Line 118	C++
SofaSimulationCore.dll!sofa::simulation::CollisionVisitor::processNodeTopDown(sofa::simulation::Node * node) Line 36	C++
SofaSimulationGraph.dll!sofa::simulation::graph::DAGNode::executeVisitorTopDown(sofa::simulation::Visitor * action, std::list<sofa::simulation::graph::DAGNode *,std::allocator<sofa::simulation::graph::DAGNode *>> & executedNodes, std::map<sofa::simulation::graph::DAGNode *,sofa::simulation::graph::DAGNode::StatusStruct,std::less<sofa::simulation::graph::DAGNode *>,std::allocator<std::pair<sofa::simulation::graph::DAGNode * const,sofa::simulation::graph::DAGNode::StatusStruct>>> & statusMap, sofa::simulation::graph::DAGNode * visitorRoot) Line 693	C++
SofaSimulationGraph.dll!sofa::simulation::graph::DAGNode::doExecuteVisitor(sofa::simulation::Visitor * action, bool precomputedOrder) Line 612	C++
SofaSimulationCore.dll!sofa::simulation::CollisionAnimationLoop::computeCollision(const sofa::core::ExecParams * params) Line 76	C++
SofaConstraint.dll!sofa::component::animationloop::FreeMotionAnimationLoop::step(const sofa::core::ExecParams * params, double dt) Line 234	C++
SofaSimulationCore.dll!sofa::simulation::Simulation::animate(sofa::simulation::Node * root, double dt) Line 245	C++
SofaGuiQt.dll!sofa::gui::qt::RealGUI::step() Line 2147	C++

The scene file is updated here

[yupeng]

Hey @Hugo,
Thanks for your kind instructions. I could export the haptic force right now.

The solution is here

[yupeng]

Oh, I make a stupid mistake: choosing the wrong component when clicking printlog. The precedure above is right. I could print out the haptic force.

What’s more, how can I store the haptic force into a file?

[yupeng]

@Hugo, Thanks for your reply. It helps a lot.
I’ve read the paper you suggested. And I’m trying to implement the method in it.

About the code, I wonder how can I register TetrahedronDiscreteIntersection into the factory. The error log is shown as the first post.

[yupeng]

Hi @Hugo, thanks for your reply.

The function of TetrahedronDiscreteIntersection is just what I want to use.

When my needle inserts into the tet mesh, I have to determine which tetrahedron collides with the needle (represented as a point collision model currently).
However, there are no intersection methods that can handle this.

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