detection output local min distance

[anyCli0]

hello i am doing a real time mechanical simulation of surgical microclipping of aneurysms. An initial implementation is based on the collision of the clip model with a simplified geometry in the shape of a cylinder. by starting the simulation there are no problems, I can get the clip close to the cylinder by controlling it from the keyboard, open it and close it. At the moment when the collision models detect each other, nodes appear in the scene graph which I have not created (comprising a mechanical object and a barycentric mapping), relating to the entity in contact with the collision models. then the programme crashes and the simulation stops. Here some images to describe better the problem
![then](https://github.com/user-attachments/assets/3f1b60f6-0af9-4e0d-85b5

[anyCli0]

[anyCli0]

I found the cause but i cannot solve it. The new node created is linked to the output detection of the local min distance. As a matter of fact if I change the intersection algorithm (MinProximityIntersection) during the simulation more nodes are created (Linecollisionmodel-linecollisionmodel, pointcollisionmodel-traingularcollisionmodel). Do you know how to fix it?

[hugtalbot]

Hi @anyCli0

Could you share

• your scene please (xml or python)?
• the console output when the simulation crashes

Also, have you followed the SOFA tutorial on how to build a simulation?

[anyCli0]

To write my code I have followed the implementation chosen in the following link:
https://gitlab.com/altairLab/probe-tissue-simulation
here my code and the console ouput

########## SIG 11 - SIGSEGV: segfault ##########
  sofa::helper::BackTrace::dump
  sofa::helper::BackTrace::sig
  log2f
  OPENSSL_Applink
  _C_specific_handler
  _chkstk
  RtlFindCharInUnicodeString
  KiUserExceptionDispatcher
  sofa::component::linearsolver::direct::SparseLDLSolver<sofa::linearalgebra::CompressedRowSparseMatrix<double,sofa::type::vector<double,sofa::type::CPUMemoryManager<double> >,sofa::type::vector<unsigned int,sofa::type::CPUMemoryManager<unsigned int> > >,so
  sofa::component::linearsolver::MatrixLinearSolver<sofa::linearalgebra::CompressedRowSparseMatrix<double,sofa::type::vector<double,sofa::type::CPUMemoryManager<double> >,sofa::type::vector<unsigned int,sofa::type::CPUMemoryManager<unsigned int> > >,sofa::l
  sofa::component::constraint::lagrangian::correction::LinearSolverConstraintCorrection<sofa::defaulttype::StdVectorTypes<sofa::type::Vec<3,double>,sofa::type::Vec<3,double>,double> >::addComplianceInConstraintSpace
  sofa::component::constraint::lagrangian::solver::GenericConstraintSolver::buildSystem
  sofa::core::behavior::ConstraintSolver::solveConstraint
  sofa::component::animationloop::FreeMotionAnimationLoop::step        
  sofa::simulation::Simulation::animate
  sofa::gui::qt::RealGUI::step
  QMetaObject::activate
  QTimer::timerEvent
  QObject::event
  QApplicationPrivate::notify_helper
  QApplication::notify
  QCoreApplication::notifyInternal2
  QEventDispatcherWin32::event
  QApplicationPrivate::notify_helper
  QApplication::notify
  QCoreApplication::notifyInternal2
  QCoreApplicationPrivate::sendPostedEvents
  qt_plugin_query_metadata
  QEventDispatcherWin32::processEvents
  DispatchMessageW
  DispatchMessageW
  QEventDispatcherWin32::processEvents
  qt_plugin_query_metadata
  QEventLoop::exec
  QCoreApplication::exec
  sofa::gui::qt::RealGUI::mainLoop
  sofa::gui::common::GUIManager::MainLoop
  PyInit_Gui
  PyInit_Gui
  PyMethodDef_RawFastCallKeywords
  PyObject_MakeTpCall
  PyEval_GetFuncDesc
  PyEval_EvalFrameDefault
  PyEval_EvalCodeWithName
  PyRun_FileExFlags
  PyRun_FileExFlags
  PyRun_StringFlags
  PyRun_InteractiveOneFlags
  PyRun_SimpleFileExFlags
  Py_hashtable_copy
  Py_hashtable_copy
  Py_RunMain
  Py_Main
  OPENSSL_Applink
  BaseThreadInitThunk
  RtlUserThreadStart

[hugtalbot]

Sorry for keeping you down @anyCli0
Have you been able to solve your issue? If you need it, we could have a chat together (you are from AltairLab at Verona, right?)