Characterisation of 3D-Printed Auxetic Structures Under Low Velocity Blunt Force Impact for the Minimisation of Traumatic Brain Injury in Sport

The present study evaluates the suitability of 3D-printed PETGPolyethylene terephthalate glycol (PETG) Double Arrowhead (DAH) auxetic structuresAuxetic structures for increased impact resistance of soft-shell headgear and decreased probability of Mild Traumatic Brain Injury (MTBI), during head-to-ground impacts in sport. A suitable structureStructure should at minimum withstand 30 impacts at 100% likelihood of concussionConcussion and reliably absorb 15 J of energy from a 32 J impact to decrease the probability of MTBI from 100% to ~ 25% with less than 2% total plastic deformation. The peak force, peak acceleration, absorbed energy and cumulative damage of three distinct DAH auxetic structuresAuxetic structures were analysed by quasi-static compression and low velocity blunt force impact tests. The results of this experiment will aid the development of a new headgear technology which reduces the frequency of head trauma as a result of blunt force impact. This decreases the incidence of long-term effects induced by MBTIs.