Study On The Scanning Angle Destabilization Of Parachuting Terminal-sensitive Sub-monition

Stable scanning technology is one of key technology of terminal-sensitive projectile.The main factors of stable scanning technology such as fall speed,rotating speed and scanning angle will affect the weapon system action process and performance.The study of motion law and control of scanning angle of terminal-sensitive sub-monition is the major work of the development of terminal-sensitive projectile stable scanning plat,the major work of this paper is studying on scanning angle motion law and control based on parachuting terminal-sensitive sub-monition.Firstly,the foreign and domestic advancement of terminal-sensitive projectile and relevant key technology were described,the destabilization phenomenon of scanning angle in the engineering is introduced,the purpose and significance of this study was pointed out.Secondly,parachute-projectile system force analysis of stable scanning period were executed,three-rigid body stable scanning period dynamic model of parachute-projectile system was established.Thirdly,according to engineering practice and simulation analysis,the influence actors of scanning angle were analyzed,the differential equations of motion of projectile,which contains mass,hang distance,moment of inertial and stable scanning rotating speed,were established,the easy and useful stable criterion of scanning angle were produced and the simulation verification were executed.Finally,based on the differential equations of motion of projectile established,MATLAB simulation program were produced,the relevant factors which influence on scanning attitude were analyzed,the law of initial angle,rotating speed,moment of inertial and hang distance which affected scanning angle and destabilization rotating speed were analyzed emphatically,moment of inertial and rotating speed stable range for parachuting terminal-sensitive sub-monition stable scanning were given out,the optimum measure of terminal-sensitive projectile structure design pointed out in this paper had been proved correct by the comparison of experiment results and the theoretical simulation data.The research showed that the initial attitude and angle speed affected stable transient time but didn't affect the average of scanning angle.Rotating speed and motion of inertial affected scanning angle stronger,hang distance only affected scanning angle stronger in destabilization period.Based on the research,the terminal-sensitive sub-monition structure design measure were raised:for the terminal-sensitive sub-monition which rotating axis is the minimum inertial principal axis,the other two principal inertial moments should be designed equal so that the terminal-sensitive sub-monition scanning angle could keep stable at varied rotating speed.For the terminal-sensitive sub-monition which had a small quotient of the maximum and the maximum principal inertial moment,the medium principal inertial moment had no influence on the stability of scanning angle.For the terminal-sensitive sub-monition which had a bigger quotient of the maximum and the maximum principal inertial moment,it should reduce the difference of the maximum and the medium principal inertial moment,the smaller difference will be beneficial to the stability of scanning angle.The research results of this paper would be helpful for the correct selection of stable scanning factors and the general structure optimization of the terminal-sensitive sub-monition.