Modeling And Simulation Of Moving Posture Of Projectile In Chamber Based On Optical Characteristics

When the projectile moves in the chamber,it will produce joggling,due to the inevitable factors such as yaw,impact,friction,and self-filling conditions,etc.Because of the shielding of the gun tube and the bad test environment,which cause the problems of the narrow field of vision in the chamber and the difficulty of matching the projectile in the chamber to the real-time monitoring of the moving posture parameters of projectile in the chamber.In order to solve this problem,drawing on existing visual coordinate measurement and laser interferometry,this paper designs a testing method for moving posture of projectile in the chamber based on optical dynamic projection.This method has very important engineering application value for studying the motion law of projectile in the chamber.On the basis of analyzing the moving posture of the projectile in the chamber,the imaging condition of laser beam on the diffuse reflector and the condition of the high speed camera sensing the brightness of the imaging light spot on the diffuse reflector,the mathematical model of the imaging light spot on the diffuse reflector and the mathematical model of the relative pixel points of the imaging light spots on the photosensitive material are established.And then the image of the moving track of the imaging light spot on the diffuse reflector taken by the high speed camera while the projectile is moving in the chamber is simulated.In the process of simulation image processing,first the gray level of image is processed by the weighted average method,next the image is processed by the maximum inter-class variance threshold segmentation method,and then the image is processed by the Zhang fast parallel thinning algorithm,finally the image of the centroid motion track of the imaging light spot is obtained.The centroid coordinates of the target feature points in the image of the centroid motion track of the imaging light spot are extracted by find function in the MATLAB platform,and the information of the joggling posture of the projectile in the chamber is obtained on the basis of simulation model of moving posture of projectile in the chamber.Finally,the joggling of the projectile in the chamber is simulated with the moving ofsine wave form,triangular wave form and exponential wave form.The joggling posture information added in simulation image are compared with the corresponding parameters extracted from the simulated image,the simulation model is verified to be correct in theory.The results of simulation show that:the image of the moving track of the imaging light spot on the diffuse reflector taken by the high speed camera while the projectile is moving in the chamber is simulated.By analyzing and processing the simulation image,the moving posture information of the projectile in the chamber can be obtained.The simulation model of moving posture of projectile in the chamber based on optical dynamic projection is proved to be correct in theory.