My thesis: Joshua Granter
Impact dynamics was a natural choice for fourth-year engineering student Joshua Granter’s thesis topic.
From the headgear he once wore while playing rugby to the armoured vehicles he will be working on once he’s posted to Townsville, the Lieutenant’s research has multiple applications.
His thesis is entitled The Dynamic Response of 3D-printed 2D Re-entrant Honeycomb Structures, which essentially examines how latticed protective equipment reacts under impact loading.
Auxetic (in this case, honeycomb-shaped) structures offer a higher degree of energy absorption compared to the non-auxetic equivalent, Josh explained.
These latticed structures contract, rather than expand, under compression.
“These can be used in deep-impact absorption – situations such as car crashes, or integration into helmets, or icebreakers, or even acoustic absorption, such as in plane wings.”
Using the drop tower in UNSW Canberra’s impact dynamics lab, Josh applied 25 kilograms of weight moving at 1.5 metres per second to a test specimen.
“With this kind of structure, you can scale it up to different kinds of speeds and weights, and therefore, different types of energy and strain,” Josh said.
The inspiration came from Josh’s rugby-playing days and he hopes the technology will be used to prevent injuries.
“I had a couple of experiences where the foam inside the headgear didn’t actually perform its job correctly,” he said.
“I’m interested in that kind of protective equipment where you can absorb more energy and therefore save more people from hospital visits and concussions.”
Next year he will head to Townsville to take up the position of Platoon Commander in the Australian Army.
“I’ll work with our armoured vehicles from here on, and this kind of structure can also be integrated into armoured vehicles because of its energy absorption capabilities,” Josh said.
“If a vehicle is exposed to a dynamic loading or an impact loading, this material can be integrated into that kind of system in order to protect our soldiers inside.”
Josh will graduate in December with a Bachelor’s Degree in Mechanical Engineering (Honours).