This research is about PhysVib: a software solution on the mobile platform extending an open-source physics engine in a multi-rate rendering architecture for automatic vibrotactile feedback upon collision events. PhysVib runs concurrently with a physics engine at a low update rate and generates vibrotactile feedback commands at a high update rate based on the simulation results of the physics engine using an exponentially-decaying sinusoidal model. We have evaluated the perceptual performance of PhysVib through several user experiments and it is an effective solution for providing physically plausible vibrotactile responses while reducing application development time to great extent.  PhysVib GitHub: https://github.com/maharaga/PhysVib