Dynamic Performance Analysis And Optimization Design Of Metal Plate Spring Vibration Isolator

This research project comes from The 14th Research Institute of China Electronics Technology Group Corporation. The main purpose is to study the dynamic performance of metal plate spring vibration isolator. The metal plate spring vibration isolator is mainly used for vibration isolation and damping of shipboard electronic cabinet when suffering from the strong impact of torpedo explosion.The system of metal plate spring vibration isolator belongs to strongly non-linear system. In this paper, the mechanism of vibration isolation, vibration damping and impact resistance about metal plate spring vibration isolator is to be discussed and the dynamic differential equation of metal plate spring vibration isolator vibration system is to be established according to principle of mechanics. The contact force of metal plate spring vibration isolator in working process and dynamic performance of its system is analyzed, referring to finite element method. Through the comprehensive optimization strategy, combining with finite element analysis, the main parameters of vibration isolator are to be optimized.The main research work and conclusions are as follows:1). According to the working principle of metal plate spring vibration isolator and the material mechanics theory, through force analysis on vibration isolator's structure, the friction contact curve was calculated using finite element method and the friction contact force expression was fitted by polynomial approximation. The dynamic equation of vibration system was built up. Through analysis of the dynamic equation, the responses of the system under different exciting forces, as well as the impact of response were studied. The harmonic excitation and rectangular pulse excitation of nonlinear vibration differential equation is solved by fourth-order land-falling Runge-Kutta-Felhberg algorithm. The displacement response curve, velocity response curve and acceleration response curve are obtained. The Analysis of dynamic response showed that: the metal plate spring vibration isolator with strong nonlinear dry friction damping link has good vibration isolation and buffer function.2) With solid finite element method and modal analysis, the main components modal of system is analyzed, the results show that: the structure of metal plate spring vibration isolator and electronic cabinet on impact will not produce structure resonance phenomenon, thus it is favorable to guarantee dynamic performance. The acceleration response of metal plate spring vibration isolator vibration system on impact excitation is analyzed, the results show that: when electronic cabinet loaded on metal plate spring vibration isolator, the peak acceleration response of structure can be significantly reduced on the testing impact of shock acceleration, which indicates that the metal plate spring vibration isolator has excellent isolation and shock resistance function. The intensity and stiffness of each component of metal plate spring vibration isolator on the testing impact excitation is analyzed, the results show that: the intensity and stiffness of various components meet its requirements.3) The parametric finite element model and mathematical optimization model of metal plate spring vibration isolator are established and its main parameters were optimized. The authors investigated the effect of the design variables on the impact resistance of isolator variation via the Optimal Latin Hypercube method. The optimization of the isolator is implemented by a combination of optimization strategies based on approximate model; First, the multi-island genetic algorithm(MIGA) is used to explore the region where the global optimal solution exists, then the nonlinear programming quadratic line search(NLPQL) is used to solve the accurate global optimal solution. The RSM and Kriging models are built up, and the errors of these approximate models are analyzed, the reliability of the fitting nonlinear dynamic response of the isolator is evaluated at last. According to the results of the comprehensive strategy in isolator optimization, the maximum acceleration response of bearing structure is reduced by 56.08% compared with the initial design, which indicates that the comprehensive optimization strategy is applicable and feasible.