Topology Optimization Design And Additive Manufacturing Method Of 3D Compliant Mechanism

Compliant mechanism needs less assembly in structure,and the structure can provide accurate position for precision instruments.Therefore,it is widely used in optical engineering,precision machinery,advanced manufacturing and other fields.Topology optimization method can provide innovative design for compliant mechanism.The structures obtained by this method usually have complex geometric configurations.However,the emergence of 3D additive manufacturing technology provides a fast and effective manufacturing method for complex components.In this thesis,in order to study the application and manufacture of threedimensional compliant mechanism,the topology optimization method is used to design the three-dimensional compliant positioning platform of microscope.The fused deposition method(FDM)three-dimensional additive manufacturing technology is used to manufacture.The topology optimization design of three-dimensional compliant mechanism is difficult,and the flexibility of the compliant mechanism designed by topology optimization method is difficult to use directly.Therefore,starting from the topology optimization method of planar two-dimensional compliant mechanism,this thesis takes the standard compliant gripper as an example to discuss how to take into account the manufacturability of the compliant mechanism and the deformation capability of the structure.(1)Taking plane two-dimensional compliant gripper as an example,the solid Isotropic Material with Penalization Model(SIMP)is adopted to establish the topology optimization model with the objective of maximizing mutual strain energy and the constraint condition of volume.Different spring stiffness coefficients are used to optimize the compliant gripper.The add-on optimization based on algorithm of COMSOL finite element numerical calculation software is used in the optimization process.Finally,the optimized structure without obvious flexure hinge is selected as the basic structure of 3D printing manufacturing,and it is stretched into a threedimensional entity.However,the deformation capacity of the structure is very limited.(2)Based on the three-dimensional solid formed by stretching,the main deformation area in the structure can be judged by its stress analysis diagram.Four structural redesign schemes are proposed to increase the flexibility of the compliant gripper.FDM manufacturing technology is used to manufacture four kinds of structures,and different manufacturing processes are discussed to ensure the availability of manufacturing results.Finally,the influence of different redesign schemes on the structural flexibility of the gripper is verified by the finite element simulation and the experimental platform.(3)The research of 3D compliant mechanism design and 3D printing manufacturing is carried out.Firstly,the reliability of 3D algorithm is verified through the design of 3D compliant gripper.Referring to the proposed redesign scheme,the geometric reconstruction of topology optimization results is carried out.At the same time,3D printing manufacturing of 3D gripper in the case of single material(PLA)and dual material(PLA + TPU)is realized.Considering the application of compliant parallel mechanism in the microscope positioning platform,the whole microscope system is built,and the feasibility of the microscope based on FDM manufacturing technology is verified.The X-Y axis of the flexible positioning platform is optimized to ensure the symmetry of the design structure.Finally,the optimized results are reconstructed,and the 3D printing manufacturing of the positioning platform in the case of single material and dual material is carried out.