Airbags are a staple of vehicle safety today – every new model has at least four in the cabin. Through the years, manufacturers expanded their use in different areas of the interior, such as air curtains for the side windows, and airbags for the knees of the front passengers. Some, like Volvo for example, even started putting pedestrian airbags on the bonnet. ZF Friedrichshafen AG, one of the biggest German auto suppliers, has expanded on this idea with external airbags for the side of the vehicle.
Thеse airbags would deploy moments before a crash happens in order to reduce the impact. Like their counterparts from the cabin, they can deploy in less than 100 milliseconds and are designed to protect the two side doors of the vehicle, or where the occupants rest. With the external airbags deployed, the force from the crash will be dispersed through the airbag, thus reducing the impact on the body of the car. According to ZF, this design can reduce side impact by 30 percent, while reducing the probability of injury from 20 to 30 percent.
While these airbags seem like an evolution of existing technology, they require other hi-tech features in order to work properly. Namely, a vehicle needs to have the same sensors used for self-driving technology, such as cameras, radars, and Lidar sensors. Cameras, for example, are used for better recognizing of the object that’s about to hit the vehicle, like a bicycle, motorcycle or a car. Radars, on the other hand, are great at measuring distance but don’t have the same field of view as cameras, while Lidar sensors measure distance by pulsing a laser at the surroundings, but do that much faster than the other two.
Some new vehicles are already equipped with the sensors needed for the system to work. They are used in safety technologies such as a pre-collision system with pedestrian detection, lane departure alert, active lane correction, dynamic radar cruise control, and road sign assist. Despite that, ZF’s airbags can’t be just retrofitted to an existing vehicle model, and the reason is simple – its bodywork is not designed with external airbags in mind.
That said we might see this technology in new vehicles going forward, which will have a bodywork that’s specifically designed to contain the airbag module and inflators in the side sill. However, this may prove to be challenging in the near future, as vehicle manufacturers nowadays use the same platform for over ten years, on multiple models in their lineups. According to ZF, multiple big automakers are interested in the technology, but none has put pen to paper.
Still, if the regulators give a green light to this technology, ZF says that the first vehicles with external airbags may reach the market in just two years.