Research On Topology Optimization Design And Post Processing Method Of Compliant Mechanism Based On SIMP

Compliant mechanisms have incomparable advantages over the rigid mechanisms in some way, such as independence of transmission vice, the miniaturization of structures and so on, which result from its characteristics of transmission driven by elastic deformation. They are widely used in a broad range of high-tech fields varying from aerospace to micro-electromechanical systems. The application of topology optimization makes the design of compliant mechanism free from the traditional pattern of over dependence on artificial experience, and become systematically and scientifically. Therefore, it is of prodigious application value and research significance. However, topology optimization of compliant mechanism is easily occur the one-node connected hinges problem, cause stress concentration and lead to fracture failure; on the other hand, the compliant mechanisms optimized by existing topology optimization technology are often not conform to practical projects, difficult in model extracting and manufacturing. How to efficiently decrease the one-node connected hinges, shorten the deviation between topological design and engineering practice as well as strengthen the manufacturing performance of the topology structure is essential to realize topology optimization methods for manufacturing. This paper analyzes overseas and domestic research status of topology optimization used in compliant mechanism, focus on the one-node connected hinges problem and post-processing problem, the main work includes the following aspects:Firstly, this thesis deeply investigates the research status of topology optimization used in compliant mechanism, discusses the solving procedure of Solid Isotropic Microstructures with Penalization Method(SIMP) and Parameterization Level Set Method(PLSM), as well as compares the advantages and disadvantages of SIMP and PLSM.Secondly, on the basis of previous studies, this paper proposes the mathematical model of the compliant mechanism multi-objective topology optimization problem, and combines density filtering approach with sensitivity filtering technology to reduce the one-node connected hinges problem. It makes the results meet the requirement of the structure bearing capacity, as well as improve the output characteristics. The effectiveness of the proposed method is demonstrated by two application examples.Thirdly, focus on the poor manufacturability of the topology optimization result of SIMP, this paper presents a post-processing method based on PLSM, which used to process the optimization results obtained by SIMP. This post-processing technique can eliminate the intermediate density unit and zigzag features, so it enhances the structural manufacturability, on the other hand, it helps to optimize the weak areas such as one-node connected hinges. The validity and superiority of the post-processing are verified by two numerical examples.Finally, the full paper is summarized and further research directions are proposed.