The Researches On Dynamic Characteristics And Firing Accuracy Of Large Caliber Machine Gun

In this paper, taking two new types of large caliber machine guns which are in service as researching object and the structural dynamic characteristics and accuracy of fire as the key, combining theoretical modeling and experimental study, we analyze the problem of structure dynamics caused by reducing mass of the large caliber machine guns and its effect on accuracy of fire.The concept and model of firing accuracy of large caliber machine gun are studied. The scatter accuracy model in short-range vertical screen of machine guns and the control model of muzzle object parameters are established. The dynamic stability concept of large caliber machine gun is proposed, and its principle, theoretical modeling method and experimental analysis method are systemically studied.The finite element models of two types of machine guns are set up, mainly based on the 3-dimensional beam elements, partly based on boundary elements. Modal experiment plan of the machine guns is designed and their modal analysis experiments are done. The inherent properties of structural vibration and dynamic response properties for type-02 14.5 mm anti-aircraft machine gun and type-89 12.7mm machine guns are completely realized through the method combining theory and experiment, and many valuable conclusions are obtained.The dynamic matching relation of the large caliber machine guns is studied and object function controlling the muzzle parameters is set up. Models with object function to measure the dynamic matching relation are established. The best matching relation between the firing rate and inherent frequency of type-02 14.5mm anti-aircraft machine gun is found out. At last, dynamic design principles, which should be paid attention to in the design of machine gun are put forward.