"TetrahedronFEMForceField" Explain

[Hoangn06]

Hello everyone,

I want ask about the elastic linear tetrahedral element. There are 2 comments that I can add in TetrahedronFEMForceField that I found a little bit confusing is "updateStiffnessMatrix" and "computeGlobalMatrix". Can someone explain these 2 comments that I can add? If I dont touch these two comments, their default values will be 0 so is that mean the stiffness matrix will not be updated and the global matrix will not be calculated? How does these 2 comments affected the outcome results?

Thank you and have a great day all.

[hugtalbot]

Hi @Hoangn06
TetrahedronFEMForceField is a component which implements linear elasticity over a linear tetrahedral mesh.
In the SOFA, the component of type ForceField have a specific API: a set of functions have to be implemented

• addForce
• addDForce
• addKToMatrix
• buildStiffnessMatrix

The data updateStiffnessMatrix is a parameter (true by default) which confirms that the stiffness matrix is updated at each time step.