System Identification of Debris Cloud Dynamics in Hypervelocity Impact Scenarios

Space debris poses a significant threat to operational satellites and crewed space missions. Multi-layer Whipple shield-derived and similar designs are often used for space vehicle protection. Shield design relies on either ballistic limit handbook analyses or more resource-intensive, high-fidelity numerical simulations. Medium fidelity models to efficiently predict fragmentation characteristics for shields in which debris has penetrated are not yet widely available, and would inform shield design and understanding of the space environment. In this study, image processing techniques were applied to hypersonic numerical impact simulations in multi-layer structures. These image processing techniques included including layer-specific debris distribution analysis to evaluate the patterns and transitions of debris. To quantify these transitions, dynamical system models were applied to estimate the probabilities and distributions of debris propagation between layers. Primary cases studied include 5mm and 10mm projectiles at 7 km/s impacting single layers of aluminum, Kevlar, and Nextel, with 1st and 2nd order linear system and power law model structures. Among the tested model candidates, a second-order linear system model provided the best approximation of debris distribution for single plates. Debris cloud modeling performed best for aluminum plates, while Kevlar and Nextel were only partially described. Overall, this study improves understanding of hypersonic debris dynamics in layered shielding structures, particularly an initial framework to optimizing future space debris collection systems.