OM-Sim is a MATLAB-based tool for simulating the optical behavior with respect to the dynamical behavior of mechanical systems. It simplifies and accelerates your integrated dynamical-optical modeling process. The main purpose is to simulate the optical behavior of dynamic excited optical systems, which are mechanically modeled as Multibody Systems (MBS) or Elastic Multibody Systems (EMBS) (in case of considering element deformations). The results of the mechanic simulation have to be calculated by external MBS-, EMBS- or FE-software. In order to analyze the dynamic-optical behavior, OM-Sim provides several interfaces e.g. to Ansys, MatMorembs, Simpack and Neweul-M². Furthermore, the implemented ray tracing algorithm calculates the optical properties and the imaging performance can be directly analyzed in OM-Sim using several methods based on wave optics. Simple models can even be exported to Zemax.