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Bumpers have lost their important functions of crash load isolation and inter-vehicle compatibility. Occupant compartment protection has been shifted to collapse of surrounding structures, with vehicle inoperability and occupant injury not unusual after a 50 km/h barrier impact. For higher speed vehicle and occupant survivability, a larger crash stopping distance is needed - provided by bumpers extended by radar sensing of need just before the crash. The hydraulic extended bumper was first developed by Professor James Ryan, giving vehicle driveability after a 40 km/h barrier crash, and further developed worldwide in the Experimental Safety vehicle programs, but unfortunately never developed for the commercial market. Our current work is to demonstrate the potential of compartmented airbag bumper systems inflated just before the crash to cover 1 square meter on the crash surface.

A frontal barrier crash at 48.5 km/h and a moving rigid barrier crash at 48.5 km/h into the side of a stationary car have been carried out at the Insurance Institute for Highway Safety's Vehicle Research Center, with the car having frontal then side preinflated airbag bumpers. This is a preliminary simulation of an airbag bumper system with the needed airbag inflation triggered by radar sensing of the approaching threat. The frontal airbag bumper had a high pressure airbag at 221 kPa and 23 cm thick imbedded on the outboard side of a low pressure airbag at 20 kPa whose inboard side was against the original car bumper, with a thickness of an additional 61 cm at the center line, for a combined thickness of this prototype airbag bumper of 84 cm. The low pressure airbag ruptured as expected in the frontal crash, with the airbag bumper absorbing about 19 percent of the energy of the crash due to excessive penetration into frontal structures.

We are seeking to test and adapt successful devices for child crash protection from outside the United States not now used here. Test results and possible problems are presented for a transverse infant bed, a toddler backward facing seat, and an older child booster seat with back and head supports (from Kilppan, Sweden), and the Australian “Sit-Safe” design, an inexpensive belt to go between the shoulder strap and the lap belt to insure that the shoulder belt does not touch the child's neck. We have also tested an inflated pad alternative to the upper back of the front seat bulge passive restraint of DeRampe (France) to reduce knee contact - leg straightening - body vaulting which contributes to ejection of unrestrained people from the back seat. And we are testing plastic coated side glass to explore extending the anti-lacerative glazing advance of Saint-Gobain Vitrage (France) to the even more significant potential reduction of ejection.

The injury reducing effectiveness of child safety seats in frontal crashes was evaluated, based on 36 frontal or oblique sled tests run with two or more GM three-year-old dummies in the simulated passenger compartment of a car. Unrestrained, correctly restrained and incorrectly restrained dummies were tested at the range of speeds where most nonminor injuries occur (15-35 mph). Accident data from NHTSA files were used to calibrate a relationship between the front-seat unrestrained dummies' HIC and unrestrained children's risk of serious head injuries; also between torso g's and the risk of serious torso injuries. These relationships were used to predict injury risk for the restrained children as a function of crash speed and to compare it to the risk for unrestrained children. The sled test analysis predicted that the 1984 mix of correctly and incorrectly used safety seats reduced serious injury risk by 40 percent relative to the unrestrained child, in frontal crashes.