Research On Imaging Modeling And Simulation Technology Of Space Optical Camera

It is one of the main means of space observation to use space optical camera to obtain the information of ground objects.With the increasing demand for information,the requirements for the function and performance of space optical camera are higher and higher,which puts forward high requirements for the design level of space optical camera.Due to the complexity of measurement conditions and the diversity of observation objects,it is not realistic to carry out camera experiments.With the rapid development of computer technology and calculation algorithm,computer simulation plays an increasingly significant role in the development of space optical camera.The imaging simulation system of space optical camera can provide technical support for the scheme design of space optical camera,image motion compensation calculation verification,information processing algorithm research and ground performance test.In this paper,taking the support project of Mars exploration as an example,aiming at the problem that the imaging simulation scheme of space optical camera currently has few imaging models and incomplete coverage,which is difficult to meet the simulation requirements of the camera under complex observation conditions,a space optical camera imaging simulation scheme based on the combination of satellite toolkit and open source scene graphics is designed.The main work of this paper is as follows:The influencing factors in the imaging process are simulated.The actual photographing process of space optical camera will be influenced by many factors,such as optics,electronics,information transmission and geometric imaging.A series of influence factors are divided into displacement influence model,entrance pupil irradiance influence model and transmission link influence model according to their properties.Research on visual simulation technology.Based on the comparison of different visual simulation technologies and the summary of existing visual simulation systems,a visual simulation technology based on the combination of STK and OSG is proposed to provide realistic simulation targets for the imaging simulation system of space optical camera.A series of simulations of all digital link control of space optical camera are carried out.The whole simulation system uses the ground inspection platform to send instructions,receives the instructions sent by the ground inspection platform through the main control simulation module,and transmits them to the camera optical simulation image generation module.With the changes of satellite orbit height,dimming and focusing parameters,the simulation image is updated in real time.Each module of the imaging simulation system of the space optical camera is divided,and the function of each module is designed and realized.The whole simulation system is divided into three modules,which are the creation module of the terrain environment,the main control simulation module and the camera optical simulation image generation module.The main function of the terrain environment creation module is to generate three-dimensional scene information on the surface of Mars through visual simulation technology.The main function of the main control simulation module is to receive and send various command information through 1553 B bus and RS422 bus.The main function of the camera optical simulation image generation module is to generate the detail image of the Mars surface;call the image impact model,and process the image by selecting the impact model.Finally,the experimental results show that the simulation system can not only simulate the imaging function of the space optical camera in orbit,but also verify the correctness,rationality of the camera in orbit and the accuracy of the external interface.The simulation system has been verified on the Mars exploration project verification star at present,which provides full link simulation data support for the experimental test.