Extension of Matlab’s PDE Toolbox for Developing Bionic Structural Optimization Methods: Overlapping Region Concept

In this paper, we present a novel method called Overlapping Region Concept to extend Matlab’s Partial Differential Equation (PDE) Toolbox to apply free-form surface loads during finite element analysis. In our institute, we are developing a toolbox called SG-Library in Matlab to combine multidisciplinary methods to achieve automatic design and manufacturing of medical robots and mechanisms. Recently, we have also integrated the PDE Toolbox into the SG-Library to develop some bionic methods like CAO and SKO to optimize the structure of our robots. During the implementation of these bionic methods, we have encountered the problem of applying free-form surface loads in FEM analysis. The typical workflow of PDE Toolbox separates the surface of a 3D geometry into one or more feature surfaces with sharp boundaries. Boundary conditions can be only applied to such feature surfaces. This is a remarkable drawback for the development of our methods since the surface profile of our model is constantly changing during the shape optimization. Therefore, we need to develop a method to apply free-form surface loads independent from the feature surfaces. In this paper, we use the concept of overlapping region to determine the free-form surface for applying boundary conditions. With this new method, we can achieve robust FEM analysis during the structural optimization process.