Occupant protection gets ahead of the collision

The teams' common goal: Airbags and seatbelt pretensioners are to be triggered, if necessary, even before a collision - and be precisely coordinated with how severe it will be. "The time advantage we gain can help make the decisive difference in mitigating the consequences of an accident," says Dr. Philipp Straßburger, System Architect, Predictive Safety in ZF’s Advanced Systems Development department. This is confirmed by initial simulations with a corresponding pre-crash system (prototype): The injury severity in a frontal collision with a speed reduction of around 25 km/h, for example, can be reduced by up to 50 percent.

ZF then taught the function to assess dangerous situations precisely and quickly. If, for example, two vehicles are heading toward each other, the decision algorithm has to weigh the following, among other things: How likely is it that an accident or collision will occur? What will be the positions of the vehicles before and during the collision? How long will it take for the crash to occur and at what speeds will the vehicles collide? There is hardly any time to think about this: it must be clear in very few milliseconds whether an electronic ignition command is sent to the airbags.

Cats are naturally programmed to anticipate the unavoidable. While still in the air, they reflexively bring themselves into a safer position and with their limbs stretched away. As described, the automotive pre-crash function is similar at preparing to potentially cushion the risk of injury to passengers.

It can also be adapted to the safety concept of virtually any self-enclosed passenger vehicle. In the future, this would make advanced electromechanical restraint systems possible: for example, seat belt pretensioners and airbag gas generators that use much less or even no pyrotechnics. Restraint systems that, as in the past, only trigger after a crash could do so in a more precisely timed manner and be better adapted to the specific hazardous situation. And predictive safety is even laying the foundation for the greater freedom of movement that occupants in autonomous cars would like to see. To this end, it is combined with interior monitoring systems (ImS) that detect where and how people are currently sitting.

The predictive solution thus also has its place in the upcoming ZF modular software system for integrated safety. This will link further active and passive system solutions in order to bring us closer to the goal of zero accidents and traffic fatalities. After all, only cats can count on nine lives.