Coordinates measurement method under oblique incidence based on four-light-screen

Abstract

The Four-Light-Screen is often adopted for fire dispersion measurement of small arms. Due to gravitational acceleration and the muzzle vibration are always present, leading to projectile's velocity vector no-perpendicular to the target plane of the Four-Light-Screen, which is called the oblique incidence accordingly. The oblique incidence is violated the measurable conditions of the Four-Light-Screen measurement principle. Under the muzzle position measured in advance, the muzzle position after vibration is replaced to it. The connection between the muzzle and the coordinates measured by the Four-Light-Screen is approximated as the actual trajectory. Coordinates of oblique incidence projectiles measurement methods are proposed according to establishing the equation system between the actual trajectory equation and the four detection Light-Screen plane equations of the Four-Light-Screen. Both simulation and experimental results show that the proposed methods can measure coordinates of oblique incidence projectiles. The analysis and proposed coordinates measurement methods of oblique incidence bring much to the application of external ballistic parameters measurement of small arms.