University of Michigan researchers have entered the race to build a lightweight, more affordable and more effective football helmet, with a system they've called Mitigatium. The design incorporates three different layers that are meant to blunt some dangerous physics that today's helmet designs ignore.
According to the researchers involved in the project, current helmets do a good job of preventing the peak force of an impact that can cause skull fractures, but they still let the brain dissipate the energy created by that hit.
The University of Michigan researchers are focused on creating a helmet that absorbs the negative effects of impulse – the secondary effect of an initial force or hit that may be the cause of brain injury in football players. They explain that impulse is what gives objects momentum and energy. Given the speed and weight of current football players, helmets need to be designed to block or reduce the forces of both impulse and impact.
After testing various materials in table-top collision simulators, the researchers found that the Mitigatium prototype did the best job, with a 20 percent reduction in impulse and a 30 percent reduction in peak pressure.
The three layers within the Mitigatium (seen above) include an initial layer of hard polycarbonate similar to what is used in helmet shells today, a second layer consisting of a flexible plastic, and a third layer that is described as having the consistency of dried tar. The first two layers work in tandem to reflect most of the initial force or incoming shock wave, while the third layer dissipates that force to reduce it even further. The overall effect is reduced impact to the brain.
In developing their prototype, the researchers found studies from 70 years ago that blamed impulse for damage caused by the quick, hard hits sustained in football. Yet, the results of those studies don't seem to have made it into the long-standing designs used today.
There's no indication as to when a helmet using Mitigatium might be put into production, since more studies and research need to be completed. Other universities and companies are engaged in similar projects, including the University of Washington with its Zero1 helmet, and Riddell's Speedflex that was introduced in 2014.
The video below provides more information on the University of Michigan project.
Source: University of Michigan