大口径超宽幅空间相机装调支撑结构设计与仿真分析OA

To solve the technical problems existing in the ground assembly and alignment of large-scale space optical cameras,including excessive structural stress,inaccurate measurement of the force state at support points,as well as the consequent inability to compensate for camera gravity-induced deformation and the inconsistency between the assembly-alignment state and the on-orbit imaging state.Taking a 3-meter-class off-axis three-mirror anastigmat(TMA)ultra-wide-format space camera as an example,the scheme design and simulation analysis of a high-precision assembly support fixture is presented.To meet the ground and on-orbit imaging conditions,the three-point full constraint principle is adopted,and the"Kelvin clamp"support method is utilized to effectively reduce the connection stress generated during the ground assembly and alignment process.To ensure the assembly and alignment accuracy,the fixture collects the pressure data of the support points of the assembly fixture in real time through pressure sensors,and realizes real-time dynamic adjustment of the single-point pressure in combination with active adjustment nuts,ensuring that the force state of the camera during the assembly and alignment process is highly consistent with that of the finite element simulation.On this basis,a full-machine finite element model is established with Hypermesh to compare and analyze the RMS values and rigid body displacement values of each mirror before and after the optimization of the support fixture,and the verification of the camera's optical indicators is completed through Zemax software.Finite element simulation and measured data show that the support structure can control the RMS value of the surface shape of each mirror below 0.02λ.By introducing an active force adjustment mechanism,the gravity-induced deformation of the M1,M3 and M4 mirrors is effectively controlled.The problems of stress control and gravity compensation in the ground assembly and alignment of large-scale space optical cameras are solved by this support structure,and valuable technical support is provided for the ground assembly and alignment of similar high-resolution space optical cameras.