Projectile Point Positioning Method Based On Seismic Research

In the experiments of shooting range, the locations of projectiles need to be acquired so as to retrieve the projectiles and obtain the ranges. In order to meet experimental demands of various types of modern weapon systems, a timing and positioning system for falling and bombing points,which is practical and reliable, is urgently in demand to promote range experiments’automation and informatization. With the projectiles’locations measurement’s features taken into account, the relative research were made about the projectile location model and the characteristic signals’ extractions and processing methods, which are based on emission theory of seismic waves. Therefore, the foundations are laid for the developments of these devices.The main types and features of the remotely-received seismic waves were analyzed. Besides, the emission and attenuation law of Rayleigh wave were discussed. As a result, Rayleigh wave is believed to be applied to localize the projectiles. In order to determine the noise reduction methods for seismic waves, the major influential elements to seismic waves and spectral characteristic of interference compositions were analyzed. With consideration to the features of the seismic waves caused by the projectiles’falling, the localization methods based on vibration velocity and TDOA were discussed.The localization model of straight eight lattice, right-angled eight lattice and double Y-shaped eight lattice were built. According to the simulations by Matlab, double Y-shaped eight lattice is of high localization accuracy and stable performances, compared with straight eight lattice and right-angled eight lattice.The preprocessing and wavelet noise reduction were made for the seismic waves. The characteristic parameters of seismic waves’time domain, frequency domain and time-frequency domain were analyzed. After the simulation analysis and comparisons of the methods based on feature points, correlation and high-order spectrum time delay estimation, GCC time delay estimation is of relatively high accuracy when applied into the time delay estimation of earthquake seismic waves.The research system for projectile localization experiment was made up of eight seismic sensors,amplification conditioning devices and data acquisition and processing terminal. And the data acquisition and processing software were designed. Therefore, the real-time detections and axes displays of the projectiles’drop point could be accomplished. The synchronization performances of seismic geophones, amplification conditioning devices and test systems were assessed. The detection range of seismic geophone was ascertained. The geological conditions’influences upon the energy and speed degradations were analyzed. In the reduceinscale experiments of30m×30m,the practical applicability of double Y-shaped eight lattice localization model and time-delay estimation methods were analyzed.