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Re: Questions on equations (contact laws, velocity, libraries)


> Q1. I've looked at eigen-tuxfamily library.  It doesn't seem to
> require linkage and I just need to include the following header?
>    #include <Eigen/Core> 
Yes, no lib.

> Q2. Why are we using the approximated rotations in updating Shear, and
> not quaternions.  It has been commented out in many files.  Is there
> sth that I'm not aware of?
I have no idea, but it was written by Olivier and I wouldn't trust it
(ok, I know this has become cliche in a way...; you can take it as a
joke as well). I think the real reason is that for the incremental
formulation, you don't need exact rotations since they cost too much and
the linearized form is sufficient. Bruno?

> Q3. I've been searching for the command TRVAR3 in ElasticContactLaw
> for quite long.  But couldn't find where it is defined.  The function
> is not explained in doxygen
> TRVAR3(currentContactGeometry->penetrationDepth,de1->se3.position,de2->se3.position);
Ever heard of ctags? (also try running "scons tags"). What editor/IDE do
you use? (Answer: logging macro for tracing values of 3 variables)

Cheers, v.