As we all know, side impact collisions are among the most dangerous type of road accidents, which account for nearly 700 deaths every year. Keeping this in mind, a German brand called ZF has now created an external side airbag that deploys just milliseconds before a deadly collision. This extra safety feature will provide an additional lateral crumple zone, which can help save lives and reduce occupant injuries by up to 40%. To make this possible, ZF has also networked the airbags to the vehicle’s sensor systems and has developed algorithms that are capable of detecting an impending crash and choose whether or not to deploy the airbag.
ZF is currently the only company to provide the full range of integrated vehicle safety technologies such as sensor systems, algorithms, and control units to active and passive actuators. ZF also gave a live demonstration of the prototype for the world’s first pre-crash occupant safety system with an external side airbag in Memmingen. The predictive information about an unavoidable collision also helps to further improve the effectiveness of established standard safety technology. For example, the ACR (Active Control Retractor) can warn the occupants or help secure them in a safe position in the fraction of a second, just before the collision.
The biggest challenge in the development of this system was reliably recognizing an unavoidable collision and deploying the external side airbag before the collision takes place. The system has approximately 150 milliseconds to make the decision to deploy the airbag and fill it, which is roughly the amount of time it takes a person to blink. The vehicle’s sensors first have to identify a potential impact quickly and accurately. This is possible with connected cameras, radar and lidar. Algorithms within the system software decide whether or not a collision is unavoidable and the deployment of the airbag is both possible and beneficial. If all these decisions are positive, the system ignites the inflators to fill the airbag.
In a side impact collision, the occupants may have a set of serious injuries in the chest area, if the passenger cabin is severely deformed. However, the ZF pre-crash safety system can reduce this impact by up to 30%, helping to significantly decrease the occupants’ risk of injury. The airbag has a capacity of between 280 and 400 litres, which is about five to eight times the volume of a driver airbag depending on the vehicle. Then the airbag expands upwards from the side sill to form an additional crumple zone in the door area between the A and C pillars.
“We highlighted that this safety system has the potential to significantly reduce occupant injury severity in cases of side impact collisions. Our deep understanding of the entire ’see. think. act.’ the process enables us to conceptualize and realize integrated vehicle safety solutions such as the new pre-crash safety system,” explains Uwe Class, Head of the Safe Mobility Systems department, within ZF’s Advanced Engineering team.