Design Of Mechanical Pendulum Structure Of Seismometer Based On Topology Optimization

Seismometer is widely used in the fields of seismic signal monitoring,earthquake prediction and early warning,oil and gas exploration,engineering investigation and monitoring,mine system and mine safety.For seismometer system,the mechanical pendulum is one of its important components,the frequency characteristics affect the bandwidth of the seismometer.The traditional parameter optimization method cannot change the topological structure of the mechanical pendulum,so this paper adopts the topological optimization method to design a new topological mechanical pendulum with lower frequency and higher spurious frequency,which provides a new research idea for expanding the bandwidth of the seismometer.In this paper,the working principle of the seismometer is studied,and the natural frequency of the mechanical pendulum of the seismometer affects the bandwidth of the seismometer.In order to expand the bandwidth of the seismometer,the topology optimization of the traditional seismometer mechanical pendulum is performed by using the topology optimization method of SIMP variable density method Optimized design.Using ANSYS SpaceClaim to build a finite element model of a traditional mechanical pendulum,and using ANSYS Workbench to perform static structural analysis,modal analysis,and harmonic response analysis of a traditional mechanical pendulum to determine its performance.Formulated the Topology Optimization design scheme,based on SIMP mechanical pendulum Topology Optimization mathematical model of variable density method,the minimum mechanical pendulum natural frequency of vibration as the topology goal,TopologyOptimization module of ANSYS Workbench software Topology Optimization,using MMA Topology Optimization algorithm to the traditional structure of traditional mechanical pendulum mechanical pendulum,Topology Optimization design for the new Topology by static structure analysis,modal analysis and harmonic response analysis simulation analysis on the performance.The frequency test experiment was performed on the traditional mechanical pendulum and the new topological mechanical pendulum using the guerrilla hammer excitation method.The test results show that the natural frequency and spurious frequency errors of the traditional mechanical pendulum by finite element simulation modal analysis and frequency test experiments are 0.96%.0.74%,the new topological structure mechanical pendulum finite element simulation modal analysis and frequency test experiments obtained natural frequency,spurious frequency errors were 0.62%,0.56%,verifying the traditional mechanical pendulum and new topological structure mechanical pendulum simulation model Reasonable;the natural frequency of the new topological structure mechanical pendulum was reduced from 6.30 Hz to 3.23 Hz,a decrease of 48.73%,and the spurious frequency of the new topological structure mechanical pendulum increased from 106.24 Hz to 124.83 Hz,an increase of 17.50%.The sinusoidal calibration method is used to measure the bandwidth of traditional seismometer and new topological seismometer.The experimental results show that compared with traditional seismometer,the bandwidth of new topological seismometers is 0.25 Hz to78.00 Hz,and the bandwidth of seismometer has been expanded 58.67%,Which provides a theoretical basis for extending the bandwidth of the seismometer.