[SOLVED] How to do feasible and stable physical acceleration in force feedback scene?

Hello @hugo,

I tried to build ModelOrderReduction, but failed.
I got errors like

1>HyperReducedHexahedronFEMForceField.obj : error LNK2019: unresolved external symbol “__declspec(dllimport)

So how to solve this kind of problem?

Hello, @hugo

Well, I have not solved this issue.

I tried this plugin in both Sofa 17.06 and 17.12 on Win10 64bit. The plugin requires some classes missed in the current stable Sofa revision, obviously, both 17.06 and 17.12 included.

So I search the missing classes on GitHub and add them into my Sofa. And also check the option SOFA_WITH_EXPERIMENTAL_FEATURES at CMake.

But when I compile the plugin, errors like error LNK2019: unresolved external symbol still occurs after all. So I think it is likely that the plugin is not updated to fit the current revision of Sofa.

Can you help me?

Hello @felixvanneste

The reason why I do not use the version 18.06 is that the Geomagic plugin works abnormally at that version.

When I run the offcial example Geomagic-RigidSkull.scn, the instrument would penetrate into the skull with little force feedback, which, however, can behave normally at 17.12.

Even so, I do not think the ModelOrderReduction plugin can be compiled successfully at 18.06 because there is no significant difference between 18.06 and 17.12. The missing class MechanicalMatrixMapper can still not be found in 18.06.

Hello @felixvanneste

Now I use version 18.12 to compile the MOR plugin and, however, the similar problems described from my previous post still arise.

But I tried to solve the compile errors by modifying the source code and finally I succeeded, albeit through tremendous efforts.

However, it seems that there is no standalone scn example for the MOR plugin and it should be used with the soft robot plugin. So I even downloaded the soft robot plugin later and then compiled it to see if it would work. But unfortunately, it crashed once I launched the reducedMultiGait-softRobot.pyscn.

So can you give me some guidance about it?

Wong

Hello @felixvanneste

I tried to launch the DemoSofia.py but failed because the component OglSceneFrame has been removed from Sofa since v18.12.

So I commented out the line
#node.createObject('OglSceneFrame', style="Arrows", alignment="TopRight")
at mainheader.py in Plugin STLIB and then launched the DemoSofia.py again.

But it still did not run normally because the component SparseLDLSolver always output the message “Failed to factorize, D(k,k) is zero”

Hello @felixvanneste,

I just tried your new updated MOR and it still has some compile issues on my platform.

Well, #include <SofaGeneralSimpleFem/TetrahedralCorotationalFEMForceField.inl> and
#include <SofaMiscFem/TetrahedronHyperelasticityFEMForceField.inl>
should be respectively added in HyperReducedTetrahedralCorotationalFEMForceField.cpp and HyperReducedTetrahedronHyperelasticityFEMForceField.cpp.

It is the solution.

And I want to ask two questions.

1) How can I add FreeMotionAnimationLoop into the liverFine.pyscn?

I tried to add FreeMotionAnimationLoop and GenericConstraintSolver and GenericConstraintCorrection into the scene, and then directly launched the modelOrderReduction.py.

But the generated reduced_test.py did not work properly. So what is the problem?

2) Can the reduced model be used for force feedback interaction, for instance, in a Geomagic scene? If it can, could you give me an example?

Thanks
Wong

Hello @olivier-goury

I have shared the scene file. You can use it to have a test.
https://www.dropbox.com/s/thogel4vp0av3o2/liverFine2.pyscn?dl=0

Wong

Hello @olivier-goury,

I tried to modify the scene:
https://www.dropbox.com/s/eslf3emvc8mmy8o/reduced_test2.py?dl=0

But it seemed that the HyperReducedRestShapeSpringsForceField reducedFF_liver_2 could not fix.

Was it normal?

Wong