Elastodynamic system simulation is a key procedure in computer
graphics and robotics applications. To enable these simulations, the
governing differential system is discretized in space (employing
FEM) and then in time. For many simulation-based applications
keeping the spatial resolution of the computational mesh effectively
coarse is crucial for securing acceptable computational efficiency.
However, this can introduce numerical stiffening effects that impede
visual accuracy.
We propose and demonstrate, for both linear and nonlinear force
models, a new method called EigenFit that improves the consistency
and accuracy of the lower energy, primary deformation modes, as
the spatial mesh resolution is coarsened. EigenFit applies a partial spectral decomposition, solving a generalized eigenvalue problem
in the leading mode subspace and then replacing the first several
eigenvalues of the coarse mesh by those of the fine one at rest.
EigenFit’s performance relies on a novel subspace model reduction
technique which restricts the spectral decomposition to finding
just a few of the leading eigenmodes. We demonstrate its efficacy
on a number of objects with both homogenous and heterogenous
material distributions.