在利用逆特征灵敏度分析结果的基础上，对机枪用三脚架支承结构作动力小修改，获得了使结构固有频率达到预期改善时主要结构参数（敏感参数）的修改量，修改后采用矩阵摄动法进行动态重分析。结果表明，本文所做的动力小修改方法可行、效果明显。修改结果对改善机枪的动力学特性、改进机枪结构设计具有重要的实际指导意义 Based on the results of the inverse characteristic sensitivity analysis, the modification of the main structure parameters (sensitive parameters) to make the natural frequency of the structure reach the expected improvement was obtained by modifying the support structure of the machine gun with a tripod. After the modification, the matrix perturbation method Perform dynamic reanalysis. The result shows that this method is feasible and the effect is obvious. Modification of the results to improve the kinetic characteristics of machine guns, machine guns to improve the structural design has important practical significance