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Physics-Based Character Skinning Using Multidomain Subspace Deformations
Aug. 2012 (vol. 18 no. 8)
pp. 1228-1240
T. Kim, Media Arts & Technol. Program, Univ. of California at Santa Barbara, Santa Barbara, CA, USA
D. L. James, Dept. of Comput. Sci., Cornell Univ., Ithaca, NY, USA
In this extended version of our Symposium on Computer Animation paper, we describe a domain-decomposition method to simulate articulated deformable characters entirely within a subspace framework. We have added a parallelization and eigendecomposition performance analysis, and several additional examples to the original symposium version. The method supports quasistatic and dynamic deformations, nonlinear kinematics and materials, and can achieve interactive time-stepping rates. To avoid artificial rigidity, or "locking,” associated with coupling low-rank domain models together with hard constraints, we employ penalty-based coupling forces. The multidomain subspace integrator can simulate deformations efficiently, and exploits efficient subspace-only evaluation of constraint forces between rotated domains using a novel Fast Sandwich Transform (FST). Examples are presented for articulated characters with quasistatic and dynamic deformations, and interactive performance with hundreds of fully coupled modes. Using our method, we have observed speedups of between 3 and 4 orders of magnitude over full-rank, unreduced simulations.

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Index Terms:
transforms,computer animation,deformation,eigenvalues and eigenfunctions,interactive systems,parallelization performance analysis,physics-based character skinning,multidomain subspace deformations,domain-decomposition method,articulated deformable character simulation,eigendecomposition performance analysis,computer animation,quasistatic deformation,dynamic deformation,nonlinear kinematics,interactive time-stepping rates,low-rank domain model coupling,hard constraints,penalty-based coupling forces,multidomain subspace integrator,subspace-only evaluation,constraint forces,fast sandwich transform,FST,rotated domains,full-rank unreduced simulations,artificial rigidity avoidance,Deformable models,Couplings,Animation,Force,Computational modeling,Springs,Transforms,parallelization.,Domain decomposition,deformation,subspace dynamics,reduced-order modeling,character animation
Citation:
T. Kim, D. L. James, "Physics-Based Character Skinning Using Multidomain Subspace Deformations," IEEE Transactions on Visualization and Computer Graphics, vol. 18, no. 8, pp. 1228-1240, Aug. 2012, doi:10.1109/TVCG.2012.78
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