Airbags

9.3.3 Airbag system operation

In case of a frontal collision, the impact sensors that are installed on the front of the car body send a signal to the electronic passive safety control unit. From this unit the signal enters the propellant charge, which, when triggered, emits a large amount of gas, thereby inflating the airbag.

Note
Propellant charge (short for "pyrotechnic cartridge") is a device, which is very similar to the most common shotgun cartridge, only without a capsule and warhead. It is filled with a special flammable substance, which is ignited by electric discharge.

Two- and then multi-stage airbag deployments were introduced in the process of improving the airbag system. The fact is that before the airbag was inflated at the same speed, regardless of the speed of the car. There were cases when drivers have received quite serious injuries due to the deployment of airbags in seemingly minor collisions. Therefore, at present the electronic control unit of this system also receives data on speed of the car, and depending on this parameter "decides", with what speed the airbag will work.