Numerical and Data-Driven Modeling of an Impact Test Facility for Pyroshock Qualification: Development and Validation of Contact Mechanics Models

During aerospace missions, payloads and subsystems endure extreme dynamic loads. Pyrotechnic devices, such as those used for stage separation, secondary structure deployment, or appendage release, produce high-energy transients known as pyroshocks. These pyroshocks pose a significant threat to electronic components and can compromise the success of the mission. Qualifying hardware therefore demands pyroshock testing, typically performed by striking resonant plates with projectiles or hammers to reproduce the shock response spectrum prescribed in standards. Because these tests rely on iterative, empirical tuning, experimental qualification remains time consuming and cost intensive. State of the art numerical methods can shorten this process by predicting the responses of resonant plates, but their accuracy hinges on correctly modelling impact forces and contact durations, which govern the resulting spectral content. After reviewing contact mechanics and current experimental configurations, this thesis develops a data-driven ML contact model and a numerical impact velocity predictor that couples with a pre-existing finite element model of the plate to form a complete digital twin of a pyroshock test bench. Validation against experimental data shows that these models achieve high fidelity in force,timing and velocity prediction, indicating strong potential to reduce calibration cycles and diminish qualification costs. Lastly the pyroschock testing facility at Politecnico di Torino is finalized with the dimensioning of the suspension components used for the plate and a proposal for the design af a safety plate to place behind the resonant one. The experimental setup is accompanied by the conceptualization of the complete measurement chain capable of acquiring the data needed to rigorously validate the digital twin and to study parameter sensitivity in shock testing, laying the groundwork for more efficient, repeatable, and cost-effective pyroshock qualification tests.