I must admit, this video made me squirm. In it, Mehmet Kurt, PhD, a postdoctoral research fellow in bioengineering, repeatedly triggers a helmet-covered dummy head to drop onto a hard base. Bam! Bam! Bam! Ow (me rubbing my head).
But the comfort and safety of the heads of cyclists like me is exactly the point of these tests. Kurt and his advisor David Camarillo, PhD, an assistant professor of bioengineering, compared the performance of traditional foam bicycle helmets against those of air bag helmets. The results are striking: The air bag helmet reduced head accelerations five times more than a foam helmet did, Kurt says in a Stanford press release. The article continues:
Camarillo said that the large size of the air bag helmet compared to foam bike helmets is the likely source of its success. Being larger, it can also be softer, allowing for a more cushioned fall. However, this cushioning also has a potential downside. In the testing, the air bag helmet was pre-inflated and the researchers maximized the pressure of the air inside the helmet before each drop in order to get these results.
Without the maximum amount of air, the air bag helmet could bottom out, causing the head to hit the ground with much more force than if it were wearing a traditional foam helmet. In current versions of the air bag helmet, a chemical process triggers expansion, which doesn't seem to guarantee maximum air pressure.
Camarillo also cautions that the helmet would need to clear numerous hurdles to be approved for sale in the United States.
The research appears in the Annals of Biomedical Engineering.
Previously: Building a concussion-proof helmet: A Stanford bioengineer shares his findings at TEDxStanford, Study shows football helmet safety tests may not capture common cause of concussions and A bike helmet that doubles as a stress-o-meter