Research On Structure Design For A Co-aperture System Of The Space Infrared Detection And Laser Beam Combination

The space infrared detection system and multi-band laser emitting system havebeen widely used in target recognition,laser energy transfer and informationcommunication fields.Since common requirements are needed for both two optical systems,it is,therefore,advantageous to use a co-aperture system design.Co-aperturestructure can not only reduce the whole mass,but also improve the space utilizationrate of on-board loads,and the rationality of the structure design can guarantee thecompletion of related space missions.The structure design and optical adjusting for aco-aperture system of the space infrared detection and multi-band laser emitting arestudied in detail in this paper.Firstly,space infrared detecting and multi-band laser transmitting structure of theco-aperture system are designed detailedly.Based on the combination of topology optimization and response surface method,light-weight design of the main support tube is mainly studied,the simulation results indicate that light-weight rate of the final model improved by 13%,1st natural frequency increased by 24.7%? the maximum equivalent stress decreased by 42.3% and the maximum deformation decreased by20.7% compared with initial light-weight model,the effectiveness of the proposed method is proved.It lays a foundation for ensuring the performance of optical system.Secondly,vibration response of the equivalent simplified model under static and dynamic environment is simulated and verified.Finite element method,modal superposition method and energy equivalence method are adopted to analyze theoverload,shock vibration,sinusoidal vibration and random vibration response of thesystem.The results show that the structure design can satisfy the strength and stiffnessrequirements.Finally,the scheme of adjusting and test of the optical mechanical system areproposed.Based on auto-collimation principle,the adjustment of main optical tube,the test of optical axis deviation between the infrared imaging and laser emitting branches,the installation of the imaging lens are all completed,then according to the proportional relationship of focal length and images size between the parallel light pipe and infrared imaging system,the actual focal length of infrared imaging systemis verified.The testing results show that the RMS of the main tube system is0.1141 X,@632.8nm,the optical axis deviation of near-infrared and middle-infrared branches is approximately 9.5|irad,the optical axis deviation of near-infrared and infrared imaging system is approximately 36.2p?rad,the actual focal length of infrared imaging system is 566.7mm and the error is 0.47%compared with the design value.Based on the analysis and adjusting results above,structure design of the co-aperture system in this paper can satisfy the needs of the optical system.