In a memorable scene from the sci-fi movie Demolition Man, Sylvester Stallone's car engulfs itself in a layer of protective foam just as it crashes into the side of an office building.
Airbag makers aren't quite ready to go that far, but they have developed a new generation of airbags designed to buffer a vehicle's exterior.
Some of these technologies may prove impractical. But they hint at a clean-sheet approach to safety that could shake up a segment that was starting to look mature.
Moreover, external airbags passed their initial test in Europe, where they are used to protect pedestrians in head-on collisions. The Volvo V40, for example, features an Autoliv-designed airbag that is stored under the vehicle's hood and deploys in a collision with a pedestrian to swaddle the A-pillars and windshield wipers. The rear of the vehicle's hood is lifted to cushion the impact for the pedestrian.
Now, suppliers are considering more ambitious designs. Last month, ZF TRW showcased an external side airbag that would protect cars that get T-boned by another vehicle. Three years ago, ZF TRW participated in a research consortium that built a prototype airbag stowed in the frame rails beneath the doors.
With a volume of 200 liters, the airbag was about twice the size of a conventional side curtain, so the research team used two inflators to fill it. And because the large airbag required extra time to inflate, it was designed to deploy just before the collision.