Research On Topology Optimization Method With Considering Manufacturing Constraints

Topology optimization is an effective method of designing high-performance structures.However,topology optimization often results in structures with complex geometries that are difficult and expensive to manufacture.For this reason,topology optimization is often used in the conceptual design of product structures.Considering the manufacturability of structures,the study of topology optimization methods that are directly towards manufacturing is of great importance for the efficient design of high-performance lightweight structures.Based on the analysis of the basic principles of topology optimization,a topology optimization method(Floating Projection Topology Optimization,FPTO)based on floating projection is introduced.This method uses a linear material interpolation model,constraints are progressively imposed on the element design variables by means of a floating mapping function that during the iterative process and make the structure converge to 0/1.Compared with other topology optimization methods,this method avoids the problem of material interpolation model selection and results in a structure with better performance and smoother boundaries.Based on the FPTO method,a topology optimization algorithm is proposed that can achieve the minimum length scale and the chamfering/rounding control.By simulating the physical process of burning grass,the skeleton of the topological structure is extracted and the minimum size control is achieved based on the skeleton of the structure.Meanwhile,a variable radius boundary element filtering method is proposed to determine the position of the chamfering/rounding of the structure boundary and to control the size of the chamfering/rounding by changing the size of the filtering radius.It improves the stability and reduces the stress concentration of the structure with almost no degradation of the structural performance.For the problem of material support in 3D printing,a topology optimization method for3 D printing of unsupported structures is proposed based on the FPTO method.A wedge filtering method is designed to maximize the structural performance,save printing material and improve manufacturing efficiency by using the support underneath the element to achieve self-supporting design at arbitrary overhang angle during topology optimization.