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The paper describes an evaluation of impact performance requirements for pedal cycle helmets. The paper examines the results of two related studies, evaluates other helmet test results and proposes performance criteria more effective for the amelioration of head injury. The two main studies are of pedal cycle helmet performance in real accidents (McIntosh and Dowdell IRCOBI 1992) and head impact tests conducted under conditions relevant to those occurring during pedal cycle accidents (McIntosh et al Stapp 1993). The results of other helmet evaluations are drawn upon. The paper examines a number of areas of helmet performance and focuses on head coverage and impact test criteria. The results of the studies demonstrate that pedal cycle helmets are failing to provide adequate coverage in the temporal region, and that standards tests are not sensitive to this problem.

Results from 15 side impact tests with EUROSID are reported and compared with results from 58 postmortem human subjects (PMHS). In this test series a CCMC moving deformable barrier impacted an Opel Kadett body in white under a 90° impact angle. Impact speeds were 40 km/h, 45 km/h, 50 km/h. The main goal of this research project was to find out to what extent the EUROSID is able to predict injuries which were obtained under identical test conditions using PMHS. Statistical methods described in former publications were used to calculate prediction relations derived from measured data. The body regions to be concentrated on according to PMHS tests were thorax, abdomen, and trunk of the EUROSID. Measurements taken on the dummy indicated major problems regarding interpretation of results: in some tests rib deflection was higher with 40 km/h than with 50 km/h. The abdominal switches frequently indicated high forces at 40 km/h impact speed whereas they did only once at 50 km/h.

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.

This paper compares restrained Hybrid III and THOR thoracic kinematics and cadaver injury outcome in 30° oblique frontal and in full frontal sled tests. Peak shoulder belt tension, the primary source of chest loading, changed by less than four percent and peak chest resultant acceleration changed by less than 10% over the 30° range tested. Thoracic kinematics were likewise insensitive to the direction of the collision vector, though they were markedly different between the two dummies. Mid-sternal Hybrid III chest deflection, measured by the standard sternal potentiometer and by supplemental internal string potentiometers, was slightly lower (∼10%) in the oblique tests, but the oblique tests produced a negligible increase in lateral movement of the sternum. In an attempt to understand the biofidelity of these dummy responses, a series of 30-km/h human cadaver tests having several collision vectors (0°, 15°, 30°, 45°) was analyzed.

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.

Children are often involved in automotive accidents especially as car occupants. Their protection presents particular problems in the first years of life, due to large changes in their morphology and behaviour. The aim of this paper is to contribute towards the development of a better evaluation of the child's tolerance to impact. Car accident investigations are analysed to bring information on injury mechanisms and severities. Free fall accidents are other sources of data used to correlate injuries with impact conditions. Theoretical analysis is considered for extrapolation of experimental data obtained from adult humans and animal surrogates. Then crash simulations with child cadavers and primates restrained in child seats are analysed and the estimation of tolerance levels for children is discussed.

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.

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.

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.

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 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.

A current priority in Europe and the USA is the development of improved side collision dummies. This report presents the results of sled tests with three test subject types: cadavers (PMHS), EUROSID 1 and BIOSID. Twenty one (21) cadaver tests were performed and 9 dummy tests a piece. The left side of the test subjects were impacted under one of two different test conditions: 24 km/h rigid wall and 32 km/h padded wall. The cadavers were instrumented with a 12 thoracic, and triaxial pelvic accelerometer arrays. Thoracic deformation was calculated from rib accelerations. The dummies were instrumented in their standard formats, which included the ability to measure coronal plane thoracic deformation. For all test subject types and measurement locations the 3ms. acceleration standard deviations were low. Mean 3ms. accelerations showed no consistent relationship in magnitude between subject types. The measured dummy rib deformations were compared to the calculated cadaver deformations.

The study reports on the results of frontal collisions with 16 cadavers and two Hybrid III dummies with impact velocities of 48 km/h to 55 km/h and a mean sled deceleration of 17 g; mounted to the sled was the front part of a passenger compartment. The cadavers were restrained in the driver position with either 3-point belts (6% and 16 % elongation) and/or air bag with knee bolster and one case was unrestrained. In most cases, both a 12-accelerometer thoracic array and 2 chest bands were employed. In some cases the acceleration at Th6 was measured. The cadavers were autopsied and the injury severity was rated according to the AIS 90. Maximum resultant Th1, Th6, and Th12 accelerations or sternum accelerations in x-direction ranged from 35g to 78g when using 3-point belts and produced injuries ranging from a few rib fractures to unstable chest wall (flail chest).

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.