Impact dynamics at interfaces such as water or snow play a vital role in both natural and engineered systems, from diving animals and extreme sports to military applications. High-speed entry into these media generates sudden forces that can cause injury or structural damage due to limited shock absorption. Understanding how posture and morphology affect impact dynamics is key to improving safety and performance.
In this talk, we present two bio-inspired case studies that explore how form influences interface impact. The first investigates how human diving posture—feet-first, hand-first, or head-first—affects slamming force upon water entry. Time-averaged impulse measurements show that peak force increases linearly with height and varies significantly with the geometry of the initial contact point, offering insights for injury prevention in high diving.
The second study examines how red and arctic foxes dive into snow when hunting. Using 3D-printed skulls in drop tests, we quantify impact forces and model them using added mass theory adapted for granular media. Results show that sharper skulls reduce impact force, suggesting an evolutionary adaptation for safer snow entry.
Together, these studies reveal how morphology governs interface impact dynamics across different media and offer a framework that links biological strategy to engineered design.