Car airbags were first developed in the early 1950s, with the first patent filed by John W. Hetrick in 1953. They became commercially available in the 1970s and were widely adopted in the 1980s and 1990s. Modern vehicles can have up to 10 or more airbags, including front, side, curtain, knee, and rear airbags, depending on the model and safety features. The German company ZF Lifetec introduced the Active Heel Airbag, an air bag for the foot.

A large part of the impact energy is transmitted through the femur, the strongest bone in the human body. However, tests have shown that when the seat is tilted backwards, the distance between the heel and the support increases and the connection with the floor is no longer optimal, requiring an additional point of support for the heel.

The Active Heel Airbag reduces the risk of foot injury by allowing the knee to hit the air bag at an optimal angle, maximizing its protective function. In the normal seating position, the vehicle floor provides sufficient support for the feet of the driver and front passenger, ensuring a stable support point for the heels and a controlled knee path. However, tests have shown that when the seat is tilted back, the resistance to the feet increases, so additional support is needed.

The Active Heel Airbag is integrated directly into the footwell and in the event of a collision, the airbag inflates under the floor mat. The system can be adapted to almost any car model and will be available to car manufacturers from 2028.

Source: ZF Lifetec