Design And Analysis Of Simplified Folding Mechanism Of Space Telescope

Small deployable space telescopes are the current research hotspots,which require large folding ratios,high deployment accuracy,vibration resistance,and high precision adjustment.Most of the existing literature focuses on the fixed structure of large-aperture space telescopes,and there are few reports on the research of deployable space telescopes.The paper designs an unfoldable space telescope frame structure,with the folding and unfolding mechanism and the adjustment mechanism as the key elements.The folding mechanism is designed as a one-dimensional unfolding structure of carbon fiber composite rod system with three layers,which are mounted vertically to each other.The adjustment mechanism is divided into the execution module and the measurement module.The measurement module of the adjustment mechanism adopts laser displacement sensor,reflector,and XY displacement platform to obtain the target parameters,and the execution module of the secondary mirror adjustment mechanism uses multi-degree-of-freedom platform and XY displacement platform,and the execution module of the filter adjustment mechanism uses flexible sheet deformation device to complete the error adjustment of secondary mirror and filter respectively.Static and modal simulations are carried out for the overall structure.The results of the static analysis show that the deviation of the distance between the secondary mirror and the primary mirror is less than 0.01 mm,and the deviation of the distance between the filter and the secondary mirror is less than 0.02 mm when the 2G acceleration of the space telescope system is loaded on one side perpendicular to the axis,and the modal analysis shows that the first order resonance frequency of the space telescope system is >100Hz when it is in orbit.The paper uses a three-degree-of-freedom stage as the actuating module of the deployable space telescope adjustment mechanism.The results of the Matlab simulation are consistent with the Solidworks modeling and simulation results,and the oscilloscope shows that the results are smooth and within the required accuracy range.It is verified that the three-degree-of-freedom stage can be used as an actuating module of the space telescope adjustment mechanism.This paper provides a reference solution for the design of a small deployable space telescope.