AUBURN HILLS, MI /PRNewswire/ -- In 2009, more than 4000 people lost their lives in pedestrian/motor vehicle accidents across the U.S. Another 59,000 pedestrians were injured. International automotive supplier Continental introduced a unique pedestrian protection system that fundamentally enhances the protection of pedestrians on the roads. The system features a novel type of air hose connected to two pressure sensors that builds flexibly into the bumper.
"The sensor reliably recognizes collisions with pedestrians and supplies the safety systems with the information they need to trigger protective measures," said Scott Morell, Passive Safety Engineering Director for Continental's North American region. Within 10 to 15 milliseconds of an impact, the active hood of the vehicle is triggered and raised by special actuators. This prevents the pedestrian who has been hit from being severely injured or killed by the impact with the hood and underlying engine block. The extra space provided between the hood and engine can considerably mitigate the consequences of the accident.
Until now, fiber optics or acceleration sensors have been used as the sensors for detecting collisions with pedestrians. The pressure hose sensor that Continental has developed in partnership with Daimler is a new system, offering a range of advantages. For example, it is easy to integrate into any vehicle because it can be flexibly adapted to the shape of the chassis. "This means that there are no restrictions on vehicle developers if they alter a vehicle's design—as part of a facelift, for example," said Morell. "What's more, the system's technology is extremely robust and offers high resolution and strong signal quality, which boosts the reliability of crash detection."
The crash sensor consists of a hose laid across the entire width of the car in its front bumper. The hose is situated directly behind the foam block fitted at the front of the vehicle to absorb energy. Standardized pressure sensors are installed at either end of the air-filled pressure hose. The same type of sensor is used to activate side-impact airbags. When a vehicle collides with an obstacle, the resulting pressure exerted on the hose through the front bumper and foam block creates a typical waveform that is detected by the two sensors at the ends of the hose and forwarded to an airbag control unit. Crash algorithms in the analysis software and speed information from the vehicle's information network enable the type of collision to be identified in a hundredth of a second. The signal relay time even allows conclusions to be drawn about the location of the impact, for example, the front right-hand corner or the middle of the vehicle. This enables the rapid activation of protection systems, which are most effective in accidents in urban traffic with a pre-crash speed of no more than 34 mph and a crash speed of between 12 and 18 mph.
Particular challenges for the sensor system include reliability and the ability to detect a collision between the vehicle and a pedestrian, regardless of whether the person is a small child or a grown man. The sensors must, with the highest degree of reliability, ascertain no-fire situations in which the protection systems must not be activated under any circumstances. Such situations include bumping the curb with the front spoiler or hitting a small animal.
With sales of approximately €20 billion in 2009, Continental is among the leading automotive suppliers worldwide. As a supplier of brake systems, systems and components for powertrains and chassis, instrumentation, infotainment solutions, vehicle electronics, tires, and technical elastomers, Continental contributes to enhanced driving safety and global climate protection. Continental is also a competent partner in networked automobile communication. Continental currently employs approximately 143,000 in 46 countries.