Flexible Energy-Absorbing Cell Structure for Multi-Axis Impact Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current helmets lack effective protection against both linear and rotational acceleration of the brain during impacts, particularly at sub-concussive speeds, and existing limb protectors are inflexible and lack directional control in energy absorption, failing to provide optimal protection against varied impact vectors.
Innovation Solution
A flexible energy absorbing system comprising cells with anisotropic geometries and varying packing densities, allowing for differential performance in different directions, which can be integrated into helmets and body armor to reduce both linear and rotational acceleration and improve breathability and comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If EPS density and stiffness are increased to pass high-speed test standards, then high-speed impact protection is improved, but sub-concussive and slow-speed impact protection deteriorates
Solution Approach 1:
The patent applies local quality by using different foam densities in different regions of the helmet. Specifically, it employs a gradient density structure where softer foam (lower density) is positioned in areas that experience sub-concussive impacts, while harder foam (higher density) is placed in regions subjected to high-speed impacts. This spatial variation in material properties allows the helmet to provide optimized protection for both sub-concussive and high-speed impact scenarios simultaneously.
2Volume of moving object
If helmet size is reduced to create smaller and slimmer helmets, then aesthetic and fit requirements are improved, but energy absorption capacity deteriorates
Solution Approach 1:
The patent applies parameter changes by systematically varying the density parameter of the foam material throughout the helmet structure. By implementing a density gradient where foam density increases or decreases in specific zones based on impact risk assessment, the design achieves enhanced energy absorption capacity within a reduced overall volume. This parameter optimization allows smaller helmets to maintain adequate protection without requiring uniform high-density foam throughout.
3Ease of manufacture
If homogeneous foam material is used throughout the helmet, then manufacturing simplicity is improved, but directional impact protection deteriorates
Solution Approach 1:
The patent applies local quality by implementing spatially varying foam densities tailored to specific impact zones. Different regions of the helmet contain foam with optimized density characteristics matched to the local impact risks - for example, higher density in areas prone to direct blows and lower density in areas experiencing rotational or sub-concussive forces. This localized material optimization provides superior directional impact protection while maintaining manufacturing feasibility through modular foam insertion techniques.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system significantly reduces peak linear and rotational accelerations by up to 23% and provides tailored protection across multiple axes, enhancing safety and comfort in helmets and limb protection by optimizing energy absorption in various impact directions.
Implementation Method 1
energy absorbing system such as expanded polystyrene (EPS) in a helmet to absorb energy as it is crushed during an impact
Implementation Method 2
the first plurality of cells and the second plurality of cells comprise an elastomeric material
Data Source
AI summary
The present disclosure relates to flexible energy absorbing systems and body armor, helmets and protective garments incorporating flexible energy absorbing systems. A flexible energy absorbing system may comprise a first plurality of cells having a first re-entrant geometry and a second plurality of cells having a second, different geometry. The first plurality of cells and the second plurality of cells may comprise an elastomeric material.