Methodology for Obtaining Contact Model Parameters of Projectile Barrel Coupled System: A Parameter Identification Approach

In this paper, the parameter identification problem of contact force model for the complex contacting surfaces between rotating band and rifling is studied. Firstly, taking the motion process of projectile in the barrel as the research object, the finite element elastoplastic dynamic model is firstly built. Then, the motion state parameter between rotating band and rifling are constructed, and the result data is formed as the reference value for parameter identification of the contact system, the input and output of the system are determined. After that, the multibody dynamic system considering the flexible effect during the launching process are established, the parameters of the contact parameter system are designed by sampling, and the dynamic response of the contact model is obtained, just like the responses in finite element model. Finally, the mapping relationship between contact parameters (contact stiffness coefficient K, damping factor D and exponent n) and identification errors is fitted by Chebyshev surrogate model, and the identification error is minimized by genetic algorithm (GA) to obtain accurate contact system parameters. In this study, the combination of finite element method and multibody dynamics method is innovative, which effectively avoids the expensive firing test, and the parameters obtained by identification ensure the accuracy of simulation calculation.