Scientists on the College of California Santa Barbara, HRL Laboratories LLC, and the U.S. Military Analysis Laboratory have developed elastic microlattice pads that may stand up to each single hits and a collection of impacts higher than present state-of-the-art foams utilized in soccer helmets. Their analysis, publishing November 27 within the journal Matter, means that the fabric could pave the best way for helmets that higher shield soccer gamers and different athletes from mind accidents brought on by repeated head hits.
Helmets utilized in each fight and American soccer require impact-absorbing supplies that shield in opposition to ongoing impacts, but it surely stays tough to design supplies that stay efficient over time with out compromising on quantity, mass, or price. Though helmet foams have developed prior to now many years, enhancements have been comparatively marginal.
“Our know-how might revolutionize soccer, batting, bicycle, and motorbike helmets, making them higher at defending the wearer and far simpler to have in your head as a result of elevated airflow,” says Eric Clough, a researcher at HRL Laboratories, a supplies science doctoral pupil on the College of California, Santa Barbara, and the lead scientist on the research.
The photopolymer-based microlattice materials shares a resemblance to the Eiffel Tower’s well-known wrought-iron design: it’s sturdy however permits air to cross by way of, a property that might preserve athletes’ heads cooler than present helmets. This construction additionally makes the fabric extremely adjustable, so engineers can simply tailor it to soak up totally different ranges and sorts of shock by tweaking its elements.
In an effort to check how properly three totally different variations of the microlattice materials soak up impacts in comparison with conventional foams, the researchers first used a double anvil fixture to simulate impacts related to those who would strike a pad located inside a helmet, permitting them to measure the response of the fabric alone with out accounting for the helmet’s form and different properties. Subsequent, they tailored the fabric into helmet pads and examined them in line with U.S. Military Superior Fight Helmet check specs, observing their skill to resist a number of consecutive blows.
The group’s finest performing microlattice materials absorbed as much as 27% extra vitality from a single impression than the present best expanded polystyrene foam and absorbed vitality as much as 48% extra vitality effectively in comparison with the highest vinyl nitrile foam throughout repeated impacts. The fabric additionally outperformed competing microlattice designs, absorbing almost 14% extra vitality from a single hit and staying intact to soak up the following spherical of impacts as an alternative of irreversibly buckling after one hit.
“A noticeable share of enchancment in impression absorption was one thing we had been hoping for, however the precise numbers had been higher than we anticipated,” says Clough. “Our testing reveals that the pads work higher than something on the present market.”
The sports activities know-how firm VICIS has licensed the microlattice pad know-how by way of HRL, and the researchers subsequent plan to analysis the fabric’s use in army head safety. Nonetheless, Clough cautions that the fabric will not be a “magic bullet” able to shielding the consumer from all head accidents.
“Wearers of helmets with our padding can take pleasure in the advantages however ought to by no means assume they’re fully shielded from damage or look to check the bounds of the product by presumably endangering themselves unnecessarily,” he says. “Even a terrific helmet can’t at all times shield you from each damage on a regular basis.”
Reference: “Elastomeric Microlattice Affect Attenuators” by Eric C. Clough, Thomas A. Plaisted, Zak C. Eckel, Kenneth Cante, Jacob M. Hundley and Tobias A. Schaedler, 27 November 2019, Matter.
This work was supported by the HeadHealthTECH Problem III, HRL Laboratories, LLC, and DARPA. Patents have been issued to HRL Laboratories beneath serial numbers 7,382,959; 8,017,193; 8,197,930; 8,663,539; and 9,738,013 by the U.S. Patent and Trademark workplace. HRL Laboratories has licensed this know-how to a helmet producer. Nonetheless, the authors don’t have any private monetary curiosity within the business success of this licensing exercise.