- Number
- 9659397
- Published
- 2017-05-23
- Filed
- 2013-03-15
- Assignee
- Disney Enterprises, Inc.
- Inventors
- Sumner; Robert, Hahn; Fabian, Coros; Stelian, Thomaszewski; Bernhard, Martin; Sebastian, Gross; Markus
- CPC
- G06T13/40
- Verdict
- Low Notable software
- Source
- Google Patents · FreePatentsOnline
The keeper's note
Applies physics-based simulation to an animator-provided character rig, solving motion equations within the rigs deformation subspace.
Abstract
A method is disclosed for applying physics-based simulation to an animator provided rig. The disclosure presents equations of motions for simulations performed in the subspace of deformations defined by an animator's rig. The method receives an input rig with a plurality of deformation parameters, and the dynamics of the character are simulated in the subspace of deformations described by the character's rig. In certain embodiments, the present disclosure provides a method that transforms stiffness values defined on rig parameters to a non-homogeneous distribution of material parameters for the underlying rig.
Background
BRIEF DESCRIPTION OF THE DRAWINGS(1) The drawings are provided for purposes of illustration only and merely depict typical or example implementations. These drawings are provided to facilitate the reader's understanding and shall not be considered limiting of the breadth, scope, or applicability of the disclosure. For clarity and ease of illustration, these drawings are not necessarily toscale.(2) FIG. 1 illustrates a set of sample keyframes generated by receiving a characterrig and a set of keyframes for some of the rig's parameters, then automatically producinganimation curves for the remaining parameters.(3) FIG. 2 illustrates an example animated sphere with an artist-created animation (top), a global translation with scaling parameters simulated (middle), and all rig parameters simulated (bottom).(4) FIG. 3 illustrates a set of elastic bar animation rigs simulated with varying stiffness values.(5) FIG. 4 illustrates a set of four elephant walk animations demonstrating different deformation modes obtained by performing physically-based high-level rig parameter computations.(6) FIG. 5 illustrates a comparison of artist-generated animation examples (top row) and an animation in which (secondary) motion is computed automatically using the disclosed method (bottom row).(7) FIG. 6 illustrates a rigged flower simulated with different rig stiffness parameters.(8) FIG. 7 illustrates a comparison of a simulation performed with a full set of parameters and a simulation performed
Claims
1. A method comprising: receiving an animation rig with a plurality of rig parameters, the rig parameters defininga deformation space for an attached surface mesh, the attached surface mesh comprising a plurality of nodes; receiving material stiffness data on a subset of the rig parameters, the material stiffness data defining a stiffness scale value for each of the subset of the rig parameters, wherein the stiffness scale value is relative to a stiffness of a homogeneous material chosen for a finite element method model derived from the attached surface mesh, using the rig and the material stiffness data to influence a physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset ofthe rig parameters, wherein the physics-based simulation of the effects of one or more ofgravity, inertia, and penalty-collisions is constrained by the deformation space of the rig; and generating a plurality of keyframes for some or all of the rig parameters of the animation rig as a result of the physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters.
6. A method comprising: receiving an animation rig with a plurality of rig parameters, the rig parameters defining a deformation space for an attached surface mesh, the attached surface mesh comprising a plurality of nodes; receiving material stiffness data on a subset of the rig parameters, the material stiffness data defining a stiffness scale value for each of the subset of the rig parameters, wherein the stiffness scale value is relative to a stiffness of a homogeneous material chosen for a finite element method model derived from the attached surface mesh; performing a physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters, wherein the physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions is constrained by the deformation space; and generating a plurality of keyframes forthe rig based on the results of the physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters.
12. A non-transitory computer readable medium comprising an instruction set configured to cause acomputing device to perform: receiving an animation rig with a plurality of rig parameters, the rig parameters defining a deformation space for an attached surface mesh, the attached surface mesh comprising a plurality of nodes; receiving material stiffness data on a subset of the rig parameters, the material stiffness data defining a stiffness scale value for each of the subset of the rig parameters, wherein the stiffness scale value is relative to a stiffness of a homogeneous material chosen for a finite element method model derived from the attached surface mesh; using the rig and the material stiffness data to influence a physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters, wherein the physics-based simulation ofthe effects of one or more of gravity, inertia, and penalty-collisions is constrained by the deformation space of the rig; and generating a plurality of keyframes for some or all of the rig parameters of the animation rig as a result of the physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters.
17. A non-transitory computer readable medium comprising an instruction set configured to cause a computer device to perform: receiving an animation rig with a plurality of rig parameters, the rig parameters defining a deformation space for an attachedsurface mesh, the attached surface mesh comprising a plurality of nodes; receiving material stiffness data on a subset of the rig parameters, the material stiffness data defining a stiffness scale value for each of the subset of the rig parameters, wherein the stiffness scale value is relative to a stiffness of a homogenous material chosen for a finite element method model derived from the attached surface mesh; performing a physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters, wherein the physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions is constrained by the deformation space; and generating a plurality of keyframes for the animation rig based on the results of the physics-based simulation of the effects of one or more of gravity, inertia, and penalty-collisions on the subset of the rig parameters.