Astrodynamics and Mission Design Enabled by Functional Materials

Abstract

The integration of functional materials within astrodynamics represents a paradigm shift away from the traditional limitations and methods of conventional spacecraft design. Rather than remaining strictly bound by rigid mass constraints and the necessity to forcefully overcome the space environment, mission architectures can now utilize functional materials to adapt to and exploit their surroundings. This evolution fundamentally expands the mission design space, with profound implications such as reduced subsystem complexity, the reallocation of critical mass budgets, and the ability to harness natural perturbations for propellantless control authority. This work further demonstrates how existing aerospace challenges can be solved by leveraging the capabilities of new materials. Specifically, this dissertation evaluates the impacts of this design philosophy across two primary topic areas: active orbital debris remediation and re-entry architectures.

The first three technical chapters address the critical hazard of small orbital debris (1 to 10 mm), a population currently exceeding 100 million pieces, which possess significant orbital lifetimes and pose lethal risks to spacecraft and crew. To mitigate this threat, the orbital deployment of Programmable Metamaterial Particle Ensembles (PMPEs), or "programmable dust," is proposed. Utilizing two novel, high-fidelity simulation frameworks developed to analyze both particle dynamics and mission-level design spaces, this work details the fundamental mechanisms and operational envelopes of PMPEs. The first is a thermo-orbit model that combines two-body dynamics with environmental perturbations and material-property-defined, thermally dependent optical transitions. The second is a statistical collision framework modeling the interaction between dust-based particle fields and orbital debris, extending the fidelity of current analytical methodologies. The analysis quantitatively demonstrates that passively controlled programmable dust fields significantly outperform traditional inert dust in both time- and mass-optimality. Furthermore, PMPEs enable flexible concepts of operations that mitigate adverse interactions with active spacecraft, establishing programmable dust as a highly scalable, state-of-the-art solution that eclipses existing remediation concepts.

The final two technical chapters investigate the integration of smart materials into interplanetary travel, specifically focusing on solar sail technologies. In conventional solar sailing mission architectures, the large-area sail is typically discarded or jettisoned upon planetary arrival, representing a significant opportunity cost. Although the primary propulsive objectives have been satisfied, the sail material remains a valuable asset for dissipating kinetic energy during the arrival phase of the mission. To resolve this inefficiency, the Shape-Shifting Sailer (3S) is introduced. By integrating shape-morphing technologies, the 3S concept enables the propulsive sail to dynamically transform into a deployed entry system, capable of aerocapture or direct entry. High-fidelity re-entry models are implemented to analyze the thermal viability and extract the expected structural loads of the 3S concept across mission profiles to Earth and other interplanetary destinations. The results from these simulations inform implementation requirements, such as geometric folding patterns and rigidizing mechanisms. Furthermore, they quantify the impact of these physical constraints on feasible 3S trajectories, specifically evaluating common solar sail maneuvers such as close solar approaches and logarithmic spirals. The implications of this research demonstrate that while current material thermal limits restrict certain entry profiles and destinations, the application of 3S expands the utility of solar sails. Ultimately, this dissertation demonstrates novel uses of smart materials in astrodynamics that enable solutions to critical problems facing spaceflight.