Research On Explicit Topology Optimization Considering Structural Manufacturability

Due to advantages of low cost and high efficiency,topology optimization is favored by various industries.As an innovative design tool,topology optimization is widely used in aerospace,automobile,ship and other fields.In recent years,the rise of additive manufacturing and the demand for structural information from traditional manufacturing industries pose some challenging issues for topology optimization.The problems of self-supporting structure design in additive manufacturing and structural complexity control of structural manufacturability among them are of great concern.However,traditional topology optimization approaches describe structural topology in an implicit way,which leads to difficulties in extracting structural geometric information.Therefore,it seems impossible for them to deal with above problems perfectly.For the aforementioned two issues,Moving Morphable Components(so called MMC)and Moving Morphable Voids(so called MMV)under the explicit topology optimization framework can give corresponding solutions in a simple and straightforward way.This is because under the explicit topology optimization framework,each boundary of the structure has an analytical expression,and the corresponding geometric information(i.e.,size,angle,normal vector,etc.)can be directly obtained through calculation.Based on the explicit topology optimization framework,the following research is carried out for problems mentioned above:Firstly,printable voids and the external boundary of structure described by B-spline curve are introduced in MMV-based approach.In the process of topology optimization,overhang angle constraints are adopted to restrict the deformation of inner voids and external boundary.The related design scheme can be directly connected with CAD system without any postprocessing.Secondly,considering that components of MMC-based approach have similar characteristics with components in actual structure,this paper proposes a counting function related to the size of the component,and achieve the complexity control of the continuum structure by reducing components and effective components,respectively.Compared with traditional topology optimization methods,the proposed approach is high efficient,intuitive and explicit.In the present paper,with numerical analysis and theoretical derivation taken into consideration,the validity of the proposed methods is verified by numerous examples.