What the Mantis Shrimp's Strike Is Teaching Engineers About Building Better Helmets

Mantis shrimp dactyl clubs absorb extreme forces without shattering. Engineers are copying the design for military helmets, vehicle armour, and sports safety equipment.

The mantis shrimp's dactyl club — the hammer-like appendage that generates strikes at 23 metres per second and withstands the forces of cavitation bubble collapse — has been studied by materials scientists for a decade as a biological model for impact-resistant composite materials. The April 2026 research into how strike force develops differently in males and females has reinvigorated materials science interest in the club's architecture by revealing developmental aspects of the structure that previous studies of adult specimens hadn't captured.

The specific structural features of the mantis shrimp dactyl club that interest engineers involve two components: the impact surface and the periodic region behind it. The impact surface is a relatively small area of hydroxyapatite — the same mineral that forms bones and teeth — oriented in a specific crystallographic configuration that directs crack propagation away from the club's interior when the impact creates stress waves. The periodic region consists of helicoidally oriented fibres — the same Bouligand structure that appears in fish scales and bone — that dissipate the energy of stress waves by forcing them to change direction repeatedly as they propagate through alternating fibre orientations.

The combination of the impact surface's crack-directing geometry and the periodic region's energy-dissipating architecture produces a structure that can absorb extreme impact forces without catastrophic failure — exactly the property that helmets, vehicle armour, and protective sports equipment need.

Current materials science applications have produced carbon fibre composites with Bouligand-inspired architectures that show significant impact resistance improvements over conventional layered composites in laboratory testing. The challenge has been manufacturing the helicoid fibre orientation in complex three-dimensional shapes — straightforward in flat panels, significantly harder in the curved geometries that helmets and vehicle components require.

The developmental research's contribution involves revealing how the mantis shrimp builds the Bouligand structure during growth — information that may inform manufacturing process design for bioinspired composites.