双限位器隔离系统的冲击响应计算及参数影响分析

Shock response calculation and effects of structural parameters on shock isolation system with double displacement restrictors

针对限位器在承受冲击载荷过程中存在二次冲击的问题,建立了双限位器冲击隔离系统数学模型,通过分段线性的杜哈梅积分对冲击方程进行了解析求解,并与阶跃速度法的冲击响应结果进行对比,分析限位器参数(刚度比、阻尼比、安装间隙)对冲击响应的影响,讨论了多岛遗传算法在限位器参数优化中的应用。研究结果表明:适当的限位器阻尼可以有效提升隔冲系统的抗冲击能力,但当阻尼较大时,不可用速度阶跃法进行计算;制定合理的优化策略,利用多岛遗传算法可以得到符合冲击要求的限位器最优参数。

In order to solve the secondary impact problem of displacement restrictors in the process of enduring impact load,the mathematical model of a shock isolation system with double displacement restrictors was established. The analytical solution for the shock isolation system was obtained by using a piecewise linear Duhamel integral method,and compared with the results by using the step velocity method. Effects of displacement restrictors＇ parameters（ stiffness ratio,damping ratio and assembled clearance） on shock responses were studied and the application of multi-island genetic algorithm in parameter optimization was discussed. The results prove that proper damping ratio of displacement restrictor can provide effective impact resistance to the system,but the equations could not be solved by the step velocity method in large damping ratio condition. Besides,by using multi-island genetic algorithm,the optimal parameters of displacement restrictor can be adjusted to meet shock isolation requirement by proposing reasonable optimization strategy.