Design and Evaluation of Additively-Manufactured MMOD Satellite Shielding

Abstract

As time progresses, space becomes more congested with micrometeoroids and orbital debris (MMOD). This increase in debris flux poses a critical threat to satellites already in orbit, manned missions, and future orbiting spacecraft. To reduce the operational impact of MMOD collisions, current protection schemes use Whipple Shields, an aluminum plate with a prescribed standoff distance, as the basis for protection. These aluminum shields are manufactured and installed on the space vehicle while on Earth, which constrains their size and shape, and ultimately, their effectiveness. These fixed shields also cannot be repaired if they are damaged during service. This work describes a prototype shield system that can be additively manufactured and installed while the vehicle is in orbit. This system, designed for manufacture via three-dimensional printing in space, would allow an operator to add shielding to a vehicle once in orbit, protecting it against MMOD traveling at hyper velocities. These on-orbit manufactured shields allow specific tailoring to more-efficiently and effectively meet mission requirements. CTH finite element code was used to simulate hypervelocity impacts (HVI) on computer-aided design (CAD) models of the prototypes. These simulations used structures made of analogous materials such as polycarbonate to make and evaluate new design parameters. The performance of different design parameters in simulations drove a redesign of the original prototype. These new designs were additively manufactured with ULTEM 9085 and underwent testing at a hypervelocity impact laboratory. Six prototypes were tested and successfully survived a hypervelocity projectile impact, indicating their potential effectiveness as spacecraft MMOD shielding.