浸河水环境对某小口径步枪的动力学影响分析

目的 研究浸河水环境对某小口径步枪自动机运动特性的影响规律。方法 采用摩擦系数仪测得在浸河水后自动机枪机框与枪机、导轨之间的摩擦系数，获得浸河水浓度对2个摩擦系数的影响规律。根据某小口径步枪的三维模型，在ADAMS平台中，建立其虚拟样机模型，并进行模型验证。在上述基础上，将不同浸河水后运动副间的摩擦系数加载到模型中，经仿真分析获得不同浸河水浓度对自动机运动特性的影响规律。结果 某小口径步枪的枪机、导轨与枪机框之间的摩擦系数随着浸河水浓度的增加而有所增大，而自动机的后坐到位速度、复进开始速度、复进到位速度以及射频都会随着浸河水浓度的增加而下降，其中，后坐到位速度在不同浸河水浓度环境下的降低幅度最小，其降低幅度小于10%，复进到位速度的降低幅度最大，为16.9%，但自动机后坐最大速度与浸河水浓度无关。结论 浸河水环境会增大运动副间的摩擦系数，增加自动机运动过程中的能量损耗，且当浸河水的质量浓度增大到20 kg/m³时，出现后坐不到位故障，运动副之间的摩擦系数对自动机的复进到位无影响。

Dynamic Influence Analysis of a Small-caliber Rifle in Immersion Water Environment

In order to study the influence of immersion water environment on the motion characteristics of a small-caliber rifle automata machine, the friction coefficient between the machine frame and the machine as well as between the machine frame and the guide rail of the automaton after immersion water was measured by friction coefficient meter, and the influence of concentration on the two friction coefficients was obtained. In accordance with the three-dimensional model of a small-caliber rifle, the virtual prototype model was established and verified on the ADAMS platform. On the basis of the above experience, the friction coefficients between the kinematic pairs after different river water immersions are loaded into the model, and the influence law of different river water concentrations on the motion characteristics of the automaton was obtained through simulation analysis. The test and simulation results show that the friction coefficient between the gun machine, the guide rail and the gun frame of a small-caliber rifle will increase with the increase of the immersion water concentration, while the recoil speed, the start speed of the re-entry, the re-entry speed and the radio frequency of the automaton will decrease with the increase of the immersion water concentration, among them, the recoil-to-position speed has the smallest decrease in the immersion water environment with different river water concentrations, with its decrease range is less than 10%, and the return-to-position speed has the largest decrease in the flooded environment with different river water concentrations, with its decrease range is 16.9%, but the maximum recoil speed of the automaton is independent of the river water concentration in the immersion water environment. Therefore, the immersion water environment will increase the friction coefficient between the kinematic pairs and step up the energy loss during the movement of the automata machine. When the immersion water concentration increases to 20 kg/m3, the recoil failure occurs, and the friction coefficient between the kinematic pairs does not affect the reentry of the automatic mechanisms.