Identification of aero-physical parameters of projectile based on maximum likelihood estimation algorithm

Abstract

The physical identification of aerodynamic parameters plays a decisive role in studying the characteristics of projectiles. During the development process of projectiles, it is an important task to accurately obtain the aerodynamic parameters of projectiles. In this paper, through a large number of experiments, the flight trajectory data of the projectile are measured, and the maximum likelihood estimation algorithm is used to physically identify the drag coefficient and lift coefficient of the projectile. First, the sensitivity coefficients of each parameter of the projectile trajectory are calculated and deduced. Second, based on the consistency and asymptotic characteristics of the maximum likelihood estimation algorithm, the sensitivity relationship between the velocity and the drag coefficient and between the position of the projectile’s center of mass and the lift coefficient is used to identify the aerodynamic physical parameters of the projectile. The results show that the maximum likelihood estimation algorithm has high identification accuracy, fast calculation speed, and low algorithm complexity, which can effectively identify the aerodynamic physical parameters of the projectile and meet practical engineering needs.