Fast update of elastic body simulation under impact load by efficient reduction method

A large number of eigenmodes are required for the realistic simulation of the object under arbitrary dynamic load such as impact load while only a few lower modes are adequate for the simulation of free vibration with initial deformation. For the accurate dynamic simulation under impact, a large amount of computer resources are required to obtain considerable number of eigenpairs. The present study presents an efficient dynamic simulation algorithm and simulation results of elastically deformable body under impact. We employ a modal analysis technique that pre-computes the eigenvalues and the corresponding eigenvectors in the framework of finite element method. For low latency time of real-time simulation, eigenmodes are computed from a reduced system constructed from the original one. To construct reduced system, energy estimation technique in the element level is proposed in the present study. Through a number of examples, it is demonstrated that the proposed method saves computational cost effectively and provides reliable real time results of the deformable solids under impact.