Adaptive Multi-resolution Volumetric Modeling of Bone Micro-structure

The emerging field of additive manufacturing with bio-compatible materials has led to personalized design of porous micro-structures used in healthcare. Complex micro-structures are characterized by freeform surfaces and spatially varying porosity. Currently, there is no CAD system that can handle the design of micro-structures due to their high complexity. This paper describes a direct expansion of our research on reconstructing 3D adaptive models of porous micro-structures. Using this approach, a designer can either manually select a Region of Interest (ROI), or define a curvature based criterion for selecting ROI while defining its level of detail. In the proposed approach, the multi-resolution volumetric model is based on designing a customized model, composed of the following stages (a) Reconstructing a multi-resolution volumetric model of a porous structure; (b) Defining ROIs and their resolution properties; and (c) Constructing an adaptive model. The feasibility of the proposed method is demonstrated on 3D models of porous micro-structures. These models are characterized by a large amount of detail and geometrical complexity. The proposed method has been applied on bone models that were reconstructed from micro-CT images. The proposed approach facilitates the porous characteristic and enables local reduction of the model complexity while optimizing the accuracy. For additive manufacturing application, the approach can be used for designing a porous micro-structure while reducing material volume and eliminating irrelevant geometric features.