The team of CU Aerospace (CUA) and the University of Illinois at Urbana-Champaign (UIUC) propose risk reduction design and analyses of a modular spacecraft addition based on our team’s CubeSail technology for accelerated spacecraft deorbiting. This technology represents a high-payoff technology using primarily atmospheric drag, but with the additional option for solar sail deorbiting from higher altitude orbits where atmospheric drag is negligible. The Phase I effort will focus on concept design, analyses, configuration trade off studies, and simulations for a CubeSail-D (Deorbit) design that can be integrated as a module on or into a larger small/nanosatellite. Unique features of the CubeSail-D design are its absence of any sail support structure, and its ability to control the solar sail blade pitch from the end of the sail and therefore enable continuous deorbiting thrust from solar photon pressure, not just aerodynamic drag. This capability of CubeSail-D becomes progressively more important at higher altitudes and is critical above 1000 km, and will also be important during times of minima in the solar sunspot cycle when atmospheric density drops and consequently drag effects decrease. Further, the ability to pitch the blade during deorbit enables alteration of the amount of aerodynamic drag seen by a CubeSail-D equipped satellite and may provide enough control authority for targeted reentry. The goal of Phase II would be delivery of a flight ready CubeSail-D demonstrator as either an add-on module or a self-contained CubeSat demonstrator.
The NASA Technology Roadmap calls for the development of Drag Sail Propulsion (TA 126.96.36.199). CubeSail-D provides a continuous effective thrust propulsion solution, providing enough potential Delta-V for deorbiting from LEO beyond the capabilities of like-sized chemical/electric propulsion options. A low-mass, low-cost deorbit capability would be very attractive for many or most of NASA LEO satellites, especially for those above altitudes of 680 km where the atmospheric density is low enough that natural decay lifetimes for reentry are >25 years.
Prior to launch, all Earth-orbiting spacecraft are required to have a concept of operations including a plan for when they reach the end of their useful life that they will be deorbited or moved to an orbit that poses no risk to other spacecraft. Thus, all government, industry, or academia satellites are potential customers for the CubeSail-D (Deorbit) deorbiting module.