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Sixty-three simulated frontal impacts using cadaveric specimens were performed to examine and quantify the performance of various contemporary automotive restraint systems. Test specimens were instrumented with accelerometers and chest bands to characterize their mechanical responses during the impact. The resulting thoracic injury severity was determined using detailed autopsy and was classified using the Abbreviated Injury Scale. The ability of various mechanical parameters and combinations of parameters to assess the observed injury severities was examined and resulted in the observation that belt restraint systems generally had higher injury rates than air bag restraint systems for the same level of mechanical responses. To provide better injury evaluations from observed mechanical parameters without prior knowledge of what restraint system was being used, a dichotomous process was developed.

The prevention of lower extremity injuries to front seat car occupants is a priority because of their potential to cause long-term impairment and disability. To determine the types and mechanisms of lower extremity injuries in frontal collisions, studies under controlled test conditions are needed. Sled tests using belt-restrained cadavers and dummies were conducted, in which footwell intrusion was simulated via a plane surface or simulated brake pedal. Human cadavers in the age range from 30 to 62 years and Hybrid III dummies were used. The footwell intrusion had both translational (135 mm) and rotational (30 degrees) components. Maximum footwell intrusion forces and accelerations were measured. The lower legs were instrumented with accelerometers and a ""six axis'' force-moment transducer was mounted in the mid shaft of the left tibia.

The number of passenger cars equipped with side air bags is steadily increasing. With the aim of investigating the mechanical responses and the injuries of the arm under the influence of a side air bag, tests in probably higher injury risk configurations with dummies and cadavers were performed. The air bag was installed at the outer side of the seat back, with the subject seated in the driver or front passenger seat of a passenger car. During the inflation of the air bag, the left or right forearm of the subject was positioned on the arm rest while the upper arm made contact with the seat back edge. The volume of the thorax air bag was 15 litres and for the thorax-head air bag 28 litres. The dummy was instrumented at the thorax c.g. shoulder, elbow and wrist with triaxial accelerometers. In the cadaver, triaxial accelerations in three orthogonal directions were measured at the upper and the lower humerus, the upper radius and the lower radius and the first thoracic vertebrae.

The number of passenger vehicles with combined 3-point belt/driver air bag restraint systems is steadily increasing. To investigate the effectiveness of this restraint combination, 48 kph frontal collisions were performed with human cadavers. Each cadaver's thorax was instrumented with a 12-accelerometer array and two chest bands. The results show, that by using a combined standard 3-point belt (6% elongation)/driver air bag, the thoracic injury pattern remained located under the shoulder belt. The same observation was found when belts with 16% elongation were used in combination with the driver air bag. Chest contours derived from the chest bands showed high local compression and deformation of the chest along the shoulder belt path, and suggest the mechanism for the thoracic injuries.

The paper presents a report about car pedestrian impact simulations. The front of a production car, which was mounted on a platform moving on rails was used as impact vehicle. The test subjects were eleven unembalmed post mortem human subjects (PMHS) in the age range of 19 to 78 years, and the Hybrid II-P dummy. The test speeds ranged from 23 to 41 km/h. Accelerations of head, thorax and abdomen were measured on the test subject as well as at the inside of both the knee and the ankle of the impacted leg. High speed films were taken from the side view. In eight cases we noticed open tibia and fibula fractures of the impacted leg; usually associated with higher impact velocity or the age of the test subject; in one additional case a scapular fracture occurred at a collision velocity of 41 km/h. In 6 cases we observed vertebral column injuries of AIS 1, in two cases of AIS 2, and in one case of AIS 3. In no case did pelvic-, thoracic (skeletal) and skull fractures occur.

This paper documents seven car/car lateral collisions with belted farside rear seat occupants. The test subjects - cadavers and US SIDs - were restrained with a 3-point belt which had an inboard upper anchoring point for the shoulder belt. The collision velocity was 50 km/h. In the cadaver tests, the maximum resultant acceleration, an average of 18 G, was located at the clivus. In the US SID a maximum of 22 G occurred at the C.G. Average shoulder belt forces in the cadavers of 1,6 KN were measured compared to 2,5 KN in the US SID. Through an analysis of the high speed films, lateral head-neck bending angles of 40 to 65 degrees for the cadavers were investigated. The calculated angular velocities were between 13 and 38 rad/s and angular accelerations between 350 and 644 rad/s2. No head, thorax or pelvic injuries were observed. Belt-induced minor injuries at the skin on the neck, neck muscles and cervical spine were observed with a MAIS 1.

Lateral impacts have been shown to produce a large portion of both serious and fatal injuries within the total automotive crash problem. These injuries are produced as a result of the rapid changes in velocity that an automobile occupant's body experiences during a crash. In an effort to understand the mechanisms of these injuries, an experimental program using human surrogates (cadavers) was initiated. Initial impact velocity and compliance of the lateral impacting surface were the primary test features that were controlled, while age of the test specimen was varied to assess its influence on the injury outcome. Instrumentation consisted of 24 accelerometer channels on the subjects along with contact forces measured on the wall both at the thoracic and pelvic level. The individual responses and resulting injuries sustained by 11 new subjects tested at the University of Heidelberg are presented in detail.

There exist two different methods to investigate the injury mechanisms and the tolerance levels, either sled tests or real road traffic accidents. Sled tests conducted at the University of Heidelberg and real accident cases examined by the University of Hannover were compared. The impact conditions of the Heidelberg sled tests were frontal collisions, with an impact velocity (Δv) of 50 km/h and decelerations of 10 g's to 20 g's. Twenty-nine tests with 3-point-belt protected cadavers in the age range 19 to 65 years were included in the Heidelberg collective. The Hannover sample contained 24 frontal accident cases (30 occupants) with a 100% overlap of the car front with the same Δv and average car deceleration range similar as the sled tests, the passenger compartment was only minimal intruded. Three-point belt protected drivers and front passengers in the age range of 18 to 71 years were included in the sample.

A test series of 12 fresh cadavers and 5 Part 572 dummies is reported. The test configuration is frontal impact sled simulation at 30 mph and aims to simulate the restraint environment of a Volvo 240 car. The test occupants are restrained in a 3-point safety belt. The instrumentation of the surrogates involves mainly 12-accelerometers in chest, 9-accelerometers in head and 3-accelerometers in pelvis. Measured values are given and discussed together with the medical findings from the cadaver tests. The occurence of submarining with cadavers and dummies is reported. A comparison is also made with earlier work where both field accidents and sled simulatations of similar violence have been reported. It is concluded that there exist differences in kinematics between the dummy and the cadaver, although peak chest acceleration is similar in both conditions. The lap belt slides over the iliac crest more frequently in the cadaver tests than in the dummy tests.