How to change the material model or material properties at each time step?

[danielcpnkimo]

Hi, I'm a using FEBio and Gibboncode to model the tissue mechanics with compressible neo-Hookean and exponential fibers distributed anisotropically by assigning each fiber orientation in the begining in the order of the elment number.
What I want to do is to update the
element centroid forces as external force at the next time step as a function of
fiber orientation, <beta>, <theta>, <phi>, fiber stiffness, <ksi>, and fiber stretch at the current time step
by my user-made solver using the output stress and fiber orientation at the current step as input. And then feedback from my solver the boundary condition, nodal body force or element centroid force at the next time step and solve the next time step continuously until the end time step is reached.
How can I take the output of the current time step and use them to impose as the boundary condition, nodal body force or element centroid force at the next time? Should I make a plugin for that?

[maas]

Hi,

If I understand what you are trying to do, then I definitely think a plugin is the way to go. The alternative would be to write some external code that would parse the FEBio output files, and then modify the input file accordingly. A plugin would eliminate the need to deal with the files since you can access the FEBio data structures directly. I may need some more detail, but it sounds like a task plugin or a callback plugin might be what you want to look at. Please take a look at the developer's manual online, which admittedly is still a bit terse on those plugins, so don't hesitate to ask questions.

Cheers,

Steve