Abstract: This paper presents an adaptive technique to animate deformable bodies in real-time. In contrast to most previous work, we introduce a multi-resolution model that locally refines or simplifies the simulated object over time in order to optimize the computational effort. We use the mixed Finite-Volume/Finite-Element method to derive fast, local discrete differential operators over irregular grids with tight error bounds. The linear elasticity equations can be simulated using an arbitrary non-nested hierarchy of volumetric meshes, allowing the computation load to be automatically concentrated where and when needed. Real-time simulation, with a guaranteed frame rate, can be achieved as demonstrated through a series of examples on our video.