Impact Attenuation Lattice Structure for Breathable Helmet Liners
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing impact attenuation materials, such as foam-based liners in helmets, exhibit inconsistent performance across varying temperatures and regions, leading to tradeoffs in weight and comfort, and lack breathability and moisture management.
Innovation Solution
A lattice structure composed of additively manufactured unit cells with angled sidewall frames and struts, forming a geometric shape without cross members, which can be stacked and angled to optimize impact absorption and distribution, using materials like polyurethane and carbon nanotubes to maintain performance across temperature ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If foam-based homogeneous impact attenuation materials are used, then impact performance is achieved, but performance becomes inconsistent across varying temperatures and regions
Solution Approach 1:
The patent applies local quality by varying the density, strut thickness, or cell geometry of the lattice structure in different regions to optimize impact attenuation for specific temperature conditions and impact locations, rather than using a uniform foam material throughout
Solution Approach 2:
The patent changes physical parameters of the lattice structure including strut diameter, cell size, wall thickness, and material composition to maintain consistent impact performance across different temperature ranges, replacing the temperature-sensitive foam materials with thermally stable lattice parameters
2Strength
If stiffer foam is used in one area of the helmet, then impact protection is improved in that area, but overall weight increases and softer foam is needed in other areas
Solution Approach 1:
The lattice structure implements local quality by adjusting strut thickness, material density, or cell geometry in specific regions to provide higher impact protection where needed while maintaining lower weight in other areas, eliminating the need for compromise with homogeneous foam
Solution Approach 2:
The patent segments the helmet liner into a lattice structure composed of discrete struts and cells, allowing independent optimization of each region's mechanical properties without affecting the entire structure's weight uniformly
3Loss of energy
If foam padding is used for impact attenuation, then impact absorption is achieved, but breathability and moisture management are reduced
Solution Approach 1:
The patent employs a porous lattice structure that provides impact attenuation through the deformable struts and cells while simultaneously enabling breathability and moisture management through the open cellular architecture, unlike closed-cell foam padding
Solution Approach 2:
The lattice structure may incorporate composite materials that combine impact-absorbing properties with moisture-wicking and breathable characteristics, integrating multiple functions into a single structure rather than relying on foam alone
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 lattice structure provides consistent impact attenuation performance across a wide temperature range, reduces weight, and enhances user comfort by improving breathability and moisture management, while allowing for customizable impact protection.
Implementation Method 1
The compressible liner absorbs impact energy and reduces the amount of energy transferred to the user's head during an impact
Implementation Method 2
lattice structure for impact attenuation
Data Source
AI summary
An impact attenuation lattice structure includes a plurality of unit cells. Each of the plurality of unit cells has a horizontal plane, a central axis, and a plurality of struts that form a plurality of sidewall frames. Each of the plurality of sidewall frames are angled relative to the central axis and the horizontal plane is perpendicular to the central axis. The plurality of unit cells are connected to one another to form a lattice structure. A first unit cell of the plurality of unit cells share one sidewall frame of the plurality of sidewall frames with a second unit cell of the plurality of unit cells adjacent to the first unit cell. The second unit cell is in an inverted position about the horizontal plane compared to the first unit cell.