# US 2014/0198106 A1 · Rig-Based Physics Simulation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0198106 A1 - Document ID: US20140198106A1 - Status: Published application - Kind: A1 - Application number: 13/843,856 - Filed: 2013-03-15 - Published: 2014-07-17 - Earliest claimed: 2013-01-11 - Assignees: Disney Enterprises, Inc. - Applicants: Disney Enterprises, Inc. - Inventors: Robert Sumner; Fabian Hahn; Stelian Coros; Bernhard Thomaszewski; Sebastian Martin; Markus Gross - Web page: https://patentgrep.com/patent/US20140198106A1 ## CPC - G06T 13/40: of characters, e.g. humans, animals or virtual beings - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## 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. An artist's control of the simulation can be enhanced by providing a method that transforms stiffness values defined on rig parameters to a non-homogeneous distribution of material parameters for the underlying rig. ## Claims ### Claim 1 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, using the rig and the material stiffness data to influence a physics-based simulation that is constrained by the deformation space of the rig; and generating keyframes on some or all of the parameters as a result of the simulation. ### Claim 2 (depends on 1) The method of claim 1, further comprising analyzing the simulation to create a set of high-level rig parameters, each high-level rig parameter being a combination of two or more of the rig parameters. ### Claim 3 (depends on 2) The method of claim 2, further comprising using one or more of the high-level rig parameters to influence a second physics-based simulation; and generating keyframes on the animation rig as a result of the second simulation. ### Claim 4 (depends on 1) The method of claim 1, further comprising using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig. ### Claim 5 (depends on 4) The method of claim 4, wherein the rig parameters can be used to calculate an elastic energy, and further wherein, using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig comprises receiving position values for a subset of the surface mesh nodes, and calculating the remaining surface mesh node position values such that the elastic energy in the deformation space is substantially minimized. ### Claim 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; performing a physics-based simulation, the simulation being constrained by the deformation space; and generating keyframes on the rig based on the results of the simulation. ### Claim 7 (depends on 6) The method of claim 6 further comprising receiving material stiffness data relating to the parameters. wherein the simulation is both constrained by the deformation space and influenced by the material stiffness data. ### Claim 8 (depends on 7) The method of claim 7, further comprising analyzing the simulation to create a set of high-level rig parameters, each high-level rig parameter being a combination of two or more of the rig parameters. ### Claim 9 (depends on 8) The method of claim 8, further comprising using one or more of the high-level rig parameters to influence a second physics-based simulation; and generating keyframes on the animation rig as a result of the second simulation. ### Claim 10 (depends on 6) The method of claim 6, further comprising using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig. ### Claim 11 (depends on 10) The method of claim 10, wherein the rig parameters can be used to calculate an elastic energy, and further wherein, using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig comprises receiving position values for a subset of the surface mesh nodes, and calculating the remaining surface mesh node position values such that the elastic energy in the deformation space is substantially minimized. ### Claim 12 A non-transitory computer readable medium comprising an instruction set configured to cause a computing 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, using the rig and the material stiffness data to influence a physics-based simulation that is constrained by the deformation space of the rig; and generating keyframes on some or all of the rig parameters as a result of the simulation. ### Claim 13 (depends on 12) The non-transitory computer readable medium of claim 12, wherein the instruction set is further configured to cause a computing device to perform analyzing the simulation to create a set of high-level rig parameters, each high-level rig parameter being a combination of two or more of the rig parameters. ### Claim 14 (depends on 13) The non-transitory computer readable medium of claim 13, wherein the instruction set is further configured to cause a computing device to perform: using one or more of the high-level rig parameters to influence a second physics-based simulation; and generating keyframes on the animation rig as a result of the second simulation. ### Claim 15 (depends on 12) The non-transitory computer readable medium of claim 12, wherein the instruction set is further configured to cause a computing device to perform using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig. ### Claim 16 (depends on 15) The non-transitory computer readable medium of claim 15, wherein the rig parameters can be used to calculate an elastic energy, and further wherein, using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig comprises receiving position values for a subset of the surface mesh nodes, and calculating the remaining surface mesh node position values such that the elastic energy in the deformation space is substantially minimized. ### Claim 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 attached surface mesh, the attached surface mesh comprising a plurality of nodes; performing a physics-based simulation, the simulation being constrained by the deformation space; and generating keyframes on the rig based on the results of the simulation. ### Claim 18 (depends on 17) The non-transitory computer readable medium of claim 17, wherein the instruction set is further configured to cause a computer device to perform the step of receiving material stiffness data relating to the parameters, and further wherein the simulation is both constrained by the deformation space and influenced by the material stiffness data. ### Claim 19 (depends on 18) The non-transitory computer readable medium of claim 18, wherein the instruction set is further configured to cause a computing device to perform analyzing the simulation to create a set of high-level rig parameters, each high-level rig parameter being a combination of two or more of the rig parameters. ### Claim 20 (depends on 19) The non-transitory computer readable medium of claim 19, wherein the instruction set is further configured to cause a computing device to perform: using one or more of the high-level rig parameters to influence a second physics-based simulation; and generating keyframes on the animation rig as a result of the second simulation. ### Claim 21 (depends on 17) The non-transitory computer readable medium of claim 17, wherein the instruction set is further configured to cause a computing device to perform using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig. ### Claim 22 (depends on 21) The non-transitory computer readable medium of claim 21, wherein the rig parameters can be used to calculate an elastic energy, and further wherein, using one or more of the rig parameters to perform inverse kinematics calculations on the animation rig comprises receiving position values for a subset of the surface mesh nodes, and calculating the remaining surface mesh node position values such that the elastic energy in the deformation space is substantially minimized.