Topology Optimization Design Of Compliant Mechanism Based On Density Projections And Configuration Stable Change

With the development of science and technology,compliant mechanisms have been widely used in robots and medical devices and etc.Topology optimization methods have also been widely used in the design of compliant mechanisms,and the research on topology optimization of flexible mechanisms has become one of the focuses of structural optimization.The existing topology optimization methods for compliant mechanisms still have some difficulties in solving hinge-like and grey problems in the topology optimization of compliant mechanisms.The final compliant mechanisms topology pursued by the design should not contain hinge-like structure,and should have a clear topological configuration.Aiming at the hinge-like and gray-scale problems in the topology optimization of compliant mechanisms,this paper studies the topology optimization method of compliant mechanisms based on Heaviside density.In order to obtain a clear optimal topology without any hinge,a structural topology optimization method is proposed.Firstly,a weighted combination compliance function is constructed,which can synthetically characterize the local stiffness characteristics of the input and output ends of the compliant mechanism.Then,in order to solve the problem of large jump of weighted composite compliance in front and back iterations when the hinge-like structure appears,a small change constraint of weighted composite compliance is introduced.In order to ensure that the volume,displacement and topology of the structure change slightly when the optimization method is solved,the variable constraint scheme is introduced to establish an optimization model for the smooth change of the configuration of compliant mechanisms.Finally,combined with MMA algorithm,a topology optimization method for compliant mechanisms with Heaviside density projection on steady configuration changes is formulated.The numerical results show that,compared with the existing methods,the calculation formula of the proposed method is simple,and a clear optimal topology without hinges can be obtained by using the proposed method.A large number of examples in this paper have proved the feasibility and validity of this method.The research work in this paper has good theoretical significance and practical value.