A key advantage of Chimera meshes is their suitability for high fidelity moving grid simulations. However, an inherent requirement and challenge is the need to establish the inter-grid communication with minimal user intervention in an efficient manner, a process called grid assembly. This paper presents a method for grid assembly that is based on collision detection. The primary benefits of this approach are that (1) it requires user-intervention only at the problem setup stage, and (2) the method is applicable to both structured and unstructured grids. Numerical results are presented for a 2-D linear cascade model of a fan-rotor system at realistic flow conditions as well as several other configurations to verify the present approach.