Artillery Shell’s Closed-loop Correction Firing Method Research

Closed-loop fire correction is a method that can correct shooting data automatically through the feedback principal based on impact point prediction offset. The essence of closed-loop fire correction projectile is an improvement of low cost ammunitions in order to raise shooting accuracy.An important link of the whole feedback system is to identify aerodynamic parameters and predict impact point. First of all, establish equation of state based on extend particle trajectory model and measurement equation based on GPS data. Then, choose Extended kalman filter, Memory attenuation kalman filter and H∞ filter to realize parameters identification, comparison and analysis of simulation results. It can be inferred that Memory attenuation kalman filter converge faster and has higher estimation accuracy than Extended kalman filter. Due to attenuation factor, Memory attenuation kalman filter increase the weight of current measurement parameters, so it can restrain diffusion. H∞ filter has a much better quality than Extended kalman filter under colored noise condition, and a worse one under additive white Gaussian noise condition instead.In order to correct initial shooting data, this paper adopts two approaches: calculation prediction method based on trajectory formula, non-linear model prediction. The first one has many advantages, such as:easier to understand, little calculation, fast prediction and higher accuracy. The second can simulate a polynomial equation with high precision after the filter tends to be stable, but can’t represent the integrated performance in short time.Closed loop fire correction projectile can correct estimation errors automatically. Only a little easy improvements are added to the traditional ammunition, can it increase shooting precision significantly. Based on the traditional correction methods, this paper put forward three new shooting methods:’Multiple emission’,’Scatted configuration, centralize fire’,’Motion compensation’.