建立了二自由度的双曲正切包装系统模型，并应用四阶龙格-库塔法对得到的冲击动力学方程进行数值求解，研究了其冲击响应特性。采用后峰锯齿脉冲作为激励，得到了关键部件的三维冲击谱，进一步讨论了频率比、脉冲激励幅值、包装材料阻尼和脉冲周期对关键部件冲击谱的影响规律。结果表明，频率比、脉冲激励幅值、包装材料阻尼和脉冲周期均对关键部件冲击响应峰值有显著影响。

Two-degree-of-freedom nonlinear packaging system model was established. The shock dynamic equations were obtained and their numerical solutions were solved by the forth order Runge-Kutta integration method. The shock response characteristics of hyperbolic tangent packaging system with critical component were investigated. Final peak saw tooth shock pulse was chosen as excitation in the computer simulation and three-dimensional shock spectra of critical components were obtained. The influences of frequency ratio, amplitude of pulse excitation, package material damp, and shock period on shock response of critical components were discussed. The results showed that frequency ratio, amplitude of pulse excitation, package material damp, and shock period all have significant influence on the peak value of shock response of critical components.