Multi-objective Topology Optimization Of Compliant Mechanism Based On SIMP

Topology optimization is one of research hotspots of compliant mechanism. In thisthesis, multi-objective topology optimization of compliant mechanism is focused, andsome related work is as follows.Firstly, SIMP is selected as the method to describe the material in order to restrictintermediate density units. Sensitivity filtering technology is adopted to try to eliminatethe checkerboard, which indicates numerical instability.Secondly, selected volume fraction as constraint and maximizing the outputdisplacement of compliant mechanism as optimization objective, a topologyoptimization model is built. Based on finite element method, a force inverter isoptimized using two algorithms, optimality criteria algorithm(OC) and the method ofmoving asymptotes(MMA), respectively. The results show that the maximum outputdisplacements obtained by the two methods are basically the same, verifying theeffectiveness of the methods.Then, the eigenvalue optimization model of compliant mechanism is establishedfor the situation of free vibration. In the process to optimize eigenvalue, PoulsenScheme is applied to inhibit local modes. From the topological graphs, we can see thatthis method is effective.Finally, based on multi-objective optimization principles and compromise planningmethod, the multi-objective optimization model is constructed, in which maximizingboth the output displacement and the first order natural frequency is selected as theobjective function. The feasibility and effectiveness of the model are verified by atypical example, in which the optimal values of each single objective function isobtained for different weight values and the best compromise solution is decided by thedecision function.