DESIGN, ANALYSIS AND TESTING OF THE ADEO PASSIVE DE-ORBIT SUBSYSTEM DEMONSTRATOR

Abstract

The space debris environment, especially in low earth orbit, is an increasing risk for all spaceflight missions. Without effective mitigation measures the debris density will increase to a level where spaceflight becomes more and more endangered. Therefore, to ensure safety for future space flight, end-of-life de-orbiting of satellites and upper stages is required by the respective standards. Deployable gossamer structures for drag sails might offer a passive de-orbit solution. The paper at hand outlines the development of such a system. It is based on the Gossamer-1 technology of the German Aerospace Center (DLR). The further development is pursued in the ESA project “Deployable Membrane” and “Architectural Design and Testing of a De-orbiting Subsystem” (ADEO). The ADEO subsystem is a drag augmentation device that uses the residual earth atmosphere present in low earth orbit. For initiation of the de-orbit manoeuvre a large surface is deployed which multiplies the drag effective surface of the satellite. Thereby the drag force is increased as well causing accelerated decay in orbit altitude. Advantageous about a drag augmentation device is that it does not require any active steering and can be designed for passive attitude stabilization. Thereby it is also applicable for non-operational, tumbling spacecraft. The ADEO subsystem consists of four coilable carbon fiber reinforced polymer (CFRP) booms that span four sail segments in a truncated pyramid shape configuration. The sail membrane is made of an aluminium coated polyimide foil. The coating thickness was chosen such that it provides sufficient protection from the space environment. The sail provides a 25m2 area spanned in a pyramidal form that is enabling passive drag attitude stabilization. The here presented work includes a detailed design of the ADEO system, complemented by an environment analysis, and the results from critical breadboard testing. Currently a fully functional demonstrator is being built. The demonstrator will be subjected to environmental testing including deployment testing in thermal-vacuum environment and ambient conditions in October 2016.