Spinning Membrane Structures

Researchers

Mélanie Delapierre
Stefan Haegeli Lohaus
Sergio Pellegrino

Description

Thin membranes are a promising architecture for large aperture, lightweight spacecraft structures like space-based antennas and solar sails, in part due to their ability to be tightly packaged for launch. Due to their inherent flexibility, prestress is required to stabilize the deployed shapes of these structures. Typically, prestress is applied via corner forces maintained by a set of deployable booms. However, there is increasing interest in lighter and mechanically simpler solutions, like the use of centrifugal stiffening which is investigated here. Our efforts have focused on characterizing the stability and dynamic behavior of spinning membrane structures through a combination of numerical simulations and laboratory experiments. Accurately predicting the onset of these instabilities is crucial in order to employ spinning membrane structures on future spacecraft.

Laboratory experiments use gravity to approximate a uniform pressure load as an analogue for the solar radiation pressure loads experienced by a spacecraft on-orbit. Our experimental setup clamps the membrane at a spinning central hub and features two controlled degrees of freedom – the hub rotation and its vertical translation. This facilitates spinning and shaking of the thin membrane disk. The entire membrane is situated in a vacuum chamber to eliminate unwanted disturbances (e.g. air resistance) and better represent the space environment. Full-field displacements are recorded using stereo Digital Image Correlation.

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Instabilities and dynamic behavior during spin-up and steady-state spin conditions have been investigated both numerically and experimentally. During spin-up, the dynamic behavior is characterized by the formation of a series of shape instabilities. This ultimately leads to a smooth axisymmetric deformed shape once steady-state spin conditions are reached. Frequency domain analyses of transverse excitations during steady-state spin conditions then reveal a jump-type instability. Several non-dimensional parameters are shown to govern the formation of instabilities in spinning membranes. This allows our results to inform the design of spinning spacecraft. Specifically, they can be used to demonstrate how fast a spacecraft must spin to avoid wrinkling.

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Additional work has focused on developing an Abaqus subroutine to study solar radiation pressure as a deformation-dependent follower load. This provides a numerical framework for studying solar elastic instabilities in spinning membrane structures, i.e., instabilities due to the interaction of solar radiation pressure and structural deformations.

Publications:

  • Sader, J., Delapierre, M., and Pellegrino, S.  (2019). Shear-induced buckling of a thin elastic disk undergoing spin-up. International Journal of Solids and Structures 166: 75-82.

  • Delapierre, M., Chakraborty, D., Sader J., and Pellegrino, S. (2018). Wrinkling of Transversely Loaded Spinning Membranes. International Journal of Solids and Structures: doi: 10.1016/j.ijsolstr.2018.01.031.

  • Delapierre, M., Haegeli Lohaus, S., and Pellegrino, S.  (2018). Nonlinear vibration of transversely-loaded spinning membranes. Journal of Sound and Vibration 427: 41-62.

  • Delapierre, M. and Pellegrino, S. (2016). Membrane spin up in a normal gravity field: experiments and simulations. SciTech 2016, San Diego, AIAA-2016-1216

  • Delapierre, M. and Pellegrino, S. (2015). Spin-stabilized membrane antenna structures, 2nd AIAA Spacecraft Structures Conference, 5-8 January 2015, Kissimmee, FL