When the airbag was first invented, the focus was on protecting the head from injuries as the body was flung forward during a severe frontal collision. In such extreme situations, the driver was at risk of hitting his head on the steering wheel while the front passenger might hit the windscreen.
The airbag, when deployed almost instantly, provided a soft cushion that could prevents hitting the steering wheel or windscreen. However, it should be noted that seatbelts must still be worn as their restraint is also needed, hence the term Supplementary Restraint System (SRS) for airbags.
Since the first airbags appeared in an Oldsmobile in the 1970s (although Mercedes-Benz is considered as having started its widespread use from the early 1980s), these safety systems have become more advanced and sophisticated with new technologies.
Airbags all round the cabin
From being just for the two front occupants, there are now airbags at the sides (front and rear) covering the window openings and even between the front occupants (to prevent the heads banging against each other).
In many models today, there are 6 airbags around the cabin and sometimes you might also see ‘7 airbags’. This extra one is usually the knee bag which first appeared in Toyota Caldina (JDM model) in 2002. This airbag, located below the steering column is to reduce serious injuries to the driver’s knees during a severe frontal collision.
Protection against foot injuries
The front passengers are more vulnerable during a collision so more attention has been given to reducing injuries. Now ZF LIFETEC (a ZF Group unit focussed on passive safety solutions)has come out with an Active Heel Airbag to protect against serious foot injuries.
The Active Heel Airbag from ZF LIFETEC is designed to increase protection against injuries in front seats. The reason for this new type of airbag is in view of seats being pushed further back which will result in leg positions being at risk of injury in a collision (extended more). This may be the case with fully autonomous cars when the driver may want to be more relaxed while the car is driving itself.
When seats can be moved further back and into so-called ‘comfort positions’, a suitable contact surface for the feet might be too far away. In the event of an accident, the resulting uncontrolled movement of the legs can increase the risk of injuries to the lower extremities. Many of these injuries are not life-threatening, but they can cause long-term damage to the musculoskeletal system of the driver and front passenger.
The Active Heel Airbag can help to create a stable heel impact point even in a relaxed seating position with the seats pushed back. It can be integrated directly into the footwell without requiring additional space. In the event of a crash, the airbag inflates under the vehicle’s floor carpet, providing the necessary heel stability.
Available from 2028
The Active Heel Airbag can be adapted to almost any vehicle model worldwide. It will be available in 2028 for automakers who want to offer their passengers seats with additional comfort positions.