Crushable
My first car was a red 1988 Ford Festiva. Some of you may remember this budget-friendly model from the Ford Motor company. It was a step up from the Yugo….but not a huge step.
When I was 17 I got into a head-on car accident in that car. I was not wearing my seatbelt. It was a pretty bad accident, but after a few stitches, I was able to walk out of the hospital and head home. The next day I went to the junkyard to recover some personal items from my beloved Festiva. I don’t remember what items I recovered, but what I do remember is seeing the damage my body had done to the car.
On either side of the steering wheel, you could see where my knees had gone into the dash. The dash had knee-shaped impressions about 6” deep, and the top of the steering wheel was bent back about 6” by my chin. I had bruises on my legs, and stitches on my chin. However, I was amazed at how much the car was crushed by the force of my body.
I told many people after that that I was lucky to be driving a crushable car because the car absorbed so much of the impact from the accident when my body flew forward. My injuries would have been worse in a more robustly built car.
“Crushability” is one of the key properties that make Epsilyte materials valuable in both safety helmets and protective packaging. Protective materials that are elastic or rubbery, compress on impact, but then bounce back. The energy of the impact is not dissipated by these types of materials. Instead, it is transmitted. However, Epsilyte materials compress on impact without the bounce back. The energy of the impact is dissipated as the micro-scale cells of encapsulated air are crushed, each little air bubble pops, dissipating the energy. In a safety helmet, this reduces the amount of impact energy that is transmitted to your head in an accident.
After this 1995 non-elastic crushing of my Festiva, it was totaled. It did not recover. I got $500 from the insurance company and bought another Festiva for $400. If you are in a bicycle accident, your foam helmet will also crush non-elastically to protect your head. When this happens, the helmet has done its job and you should always get a new helmet.