Truer-to-life testing

The function of the helmet

Protective helmets must mitigate a wide range of impact forces, from low-energy sub-concussive blunt impacts to more serious falls and collisions.

First, a quick review. The human body possesses kinetic energy when in motion. Energy scatters if it comes into contact with another force or object. It’s the helmet that helps absorb this kinetic energy upon impact rather than letting your head (and subsequently your brain) take the brunt of the force. In ballistic cases, the helmet shell is designed to catch the bullet (with performance varying by model and defined by its V50 rating— as determined through ballistic testing).

It's important to review the specific V50 performance of each helmet, as this metric directly reflects its ballistic resistance. The hard foam inside the helmet then helps absorb the residual energy from the impact. Additional soft foam padding provides comfort and cushion.

How does a helmet mitigate blunt impact?

Blunt impact occurs when an object directly strikes the head, transferring force that can affect the brain even without penetrating the skull. For example, falling and hitting your head on the ground can cause significant injury. The severity of this type of impact is closely tied to how quickly the head decelerates upon contact—the faster the stop, the greater the force transmitted to the brain. In contrast, ballistic impacts involve small, high-velocity projectiles like bullets, which pose a different kind of threat due to their speed and concentrated energy.

Team Wendy’s chemists and engineers test impact responses of foams and other impact mitigating structures in order to improve the protective capabilities of our helmet liners across a range of impact velocities. We design and formulate the foam chemistry in house with varying responses and conduct impact and compression testing both independently of a helmet and as a full system to analyze their stress-strain response allowing us to model how the system will respond to a variety of inputs.

To advance our understanding of how helmets can protect against primary blast-induced brain injuries, we’ve conducted live blast testing using advanced prototypical headforms that simulate real-world conditions. As part of the US Army’s Small Business Innovation Research (SBIR) program, we also performed shock tube testing on helmet liner materials to evaluate their response to blast waves. Additionally, we facilitated a panel discussion with leading experts to explore the latest research and innovations in mitigating blast-related brain trauma.