Study On The Inflatable Structures Technology Of Space Membrane Diffraction Mirror

Thin membrane diffraction imaging technology has become a research hotspot in the field of optical payloads due to light weight,collapsible expansion,loose tolerance and high resolution.The applications of space inflated structures in large spacecrafts are becoming more widespread,which can be used to the membrane diffraction imaging system.The design scheme of the space membrane diffraction mirror inflatable structures were proposed in this paper,in which the main mirror is a thin membrane diffractive lens,and the support structure is an inflated membrane structure.The structural design of the space membrane diffraction mirror inflatable structure was completed:inflatable support structural design,pattern and parameter design of lace structure,and the tension cables arrangement.In order to realize the folding and deployment of the space membrane diffraction mirror inflatable structure,the designs of packaging structure and the support hanger structure were carried out.The static analysis and kinetic analysis of the space membrane diffraction mirror inflatable structure were achieved based on nonlinear FEA.Through the static analysis,the stress distributions of the structure under the inflation pressure were obtained.The pre-stressed modal analysis of the inflatable membrane mirror structure was performed to obtain the frequencies and vibration modes.The harmonic response analysis was completed to determine the steady-state response of the inflatable structures under the harmonic load.The transient dynamics analysis of the inflatable structure under dynamic load was carried out,the transient vibration of the structure and the displacement,velocity and acceleration of each node were obtained.The results show that the fundamental frequency and the inflated pressure of the inflatable structure meet the design requirementsThe space thermal environment and the thermodynamic coupling effect of the inflatable structure were studied.A coupled thermal-mechanical analysis framework for the inflatable structure were developed.The thermal-mechanical coupling analysis of the inflatable structure was realized by I-DEAS and ANSYS.The transient heat transfer,thermal stress and thermal deformation of the structures in orbit were investigated.The results show that there is no thermal vibration and large thermal deformation,and the structural stiffness is good.A prototype of space film membrane mirror inflatable structure was developed and the folding deployment test was carried out.At the same time,the repeated straightness precision test and leakage test were carried out on the inflated straight pipe to verify the feasibility of the Space film diffraction mirror inflatable deployment structure.The experimental results show that the inflatable structure can be successfully expanded,and the mirror can be tensioned by the tension cables after it is fully expanded.The test results show that the axial repeat precision of the inflatable tubes meets the design requirements.