针对在小口径自动炮上使用的支架 ,将火炮身管和支架简化为空间多段有限元弹性梁单元 ,引入形函数矩阵描述梁单元的挠度 ,采用拉格朗日方程建立了考虑支架与身管耦合的有限元动力学模型。在有限元模型的基础上建立了数值计算程序并利用该模型分析和讨论了支架的作用原理 ,分析结果表明采用设计合适的支架将有助于提高小口径自动炮的射击精度 In view of the bracket used on the small-caliber automatic gun, the barrel and bracket of the gun are simplified as the space multi-section finite element elastic beam element, the shape function matrix is ​​introduced to describe the deflection of the beam element, the Lagrange equation is adopted to establish the bracket and the pipe Coupled Finite Element Dynamic Model. Based on the finite element model, a numerical calculation program is established and the principle of the bracket is analyzed and discussed. The analysis results show that using a properly designed bracket will help to improve the shooting accuracy of the small-caliber automatic gun