Real-world materials exhibit highly nonlinear mechanical behavior, but computer animation often neglects such nonlinearities. Hyperelasticity, or strain-dependent material stiffness, is one of the clear sources of nonlinearity. Correctly modeling real-world materials would require capturing strain-dependent elasticity, but hyperelasticity induces stiff differential equations that may complicate simulation, in particular for real-time computer animation. In this paper, we propose a method based on constrained optimization for the simulation of hyperelastic materials. The key novelty of our method lies on limiting elastic energy to model extremely nonlinear elasticity within a common linear co-rotational formulation. Our method is designed on a hexahedral FEM discretization to avoid locking phenomena, and is capable of solving together energy-limiting and frictional contact constraints. We show that our approach enables the simulation of a large range of hyperelastic material behaviors.

@InProceedings\{PPO13,
  author       = "Perez, Jesus and Perez, Alvaro G. and Otaduy, Miguel A.",
  title        = "Simulation of Hyperelastic Materials Using Energy Constraints",
  booktitle    = "Proc. of Congreso Español de Informática Gráfica",
  year         = "2013",
  url          = "http://gmrv.es/Publications/2013/PPO13"
}