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A major difficulty in the reconstruction of motorcycle-vehicle collisions derives from the fact that the motorcycle-rider and the motorcycle itself execute in general different trajectories after a collision with another vehicle. Accordingly, certain assumptions which may vary from case to case have to be introduced in order that the momentum and energy balance approach which is usually applied for the purpose of collision reconstruction can be adapted to calculate pre-impact circumstances. However, due to the often unfavourable mass ratio an accurate reconstruction may be impeded. A problem also exists in the assessment of post-crash decelerations of motorcycles because their motion patterns during that phase are often complex and not easily reconstructed. Likewise, in determining the course of pre-impact braking it has to be taken into account that in most motorcycles front and rear wheel brakes are applied independently.

Low-mass vehicles (LMV) are characterized by a total mass of 500 - 600 kg and an overall length of 2.5 m - 3.0 m. In order to provide sufficient transportation capacity, they should be relatively wide (1.7 m) and high (1.6 m). Occupant safety associated with such vehicles poses unique problems. According to published accident and injury statistics, a negative correlation exists between vehicle mass and injury severity in car-to-car crashes. In part, this finding can be attributed to the fact that small vehicles today are designed according to conventional design strategies involving however only a small frontal deformation zone and minimal side protection. For a LMV which is even smaller and lighter than present “small” cars another solution has to be found. A number of frontal and side impacts staged by our group with the aid of a LMV test device along with a mathematical model analysis indicate that a Rigid-Belt Body (RBB) represents a concept which is well suited for LMVs.

It is well established that properly worn seat belts reduce the incidence of severe neck injuries in car accidents in general. However, for certain configurations of nearside lateral collisions this statement has not been substantiated beyond any doubt by the published field accident data. In order to further evaluate this question, the samples of two accident investigation programs, one from Switzerland and one from France, were combined and analysed accordingly. They contain a total of 810 wearers of three point belts OAIS* > = 2, 98 of which are cases of lateral nearside impacts. In 10 % (N = 10) of this subset neck injuries of AIS >=1 were registered. 7 of those 10 cases were of a degree of AIS>=2 whereby 2 of them could directly be attributed to an immediate belt contact.

The performance of pedestrian surrogates including a mathematical model is assessed on the basis of a comparison between a sample of real accidents and the results of simulated collisions. For this purpose a representative standard test program was derived from the characteristics of real accidents. A substantial increase in average injury severity is observed in reality between impact speeds of 25 and 35 km/h. This finding is reflected in the simulated collisions insofar, as the measured or calculated loadings of the surrogate in general exceed the known tolerance limits only if the impact speed is in excess of 30 km/h. The lack of surrogate motion prior to impact is shown to cause the largest differences in comparison to real accident circumstances and their outcome. Moreover, the details of the measured accelerations during contact exhibit a large variability and their significance with regard to injury mechanisms remains to be established.

A primary cause of severe injury experienced by a pedestrian who is impacted by the front of a vehicle consists in the head impact on the hood during the loading phase of the accident. Impact speed and vehicle front geometry are the most important factors which govern the severity of this impact. The aim of the present study is to analyse the motion patterns occuring during impact, particularly those of the head, and to identify a favourable front geometry in view of a reduced injury hazard. The investigations are based on impact tests performed on a sled with a vehicle front having a variable front geometry and at different impact speeds. The surrogate was a modified 572 ATD (HUMANOID) equipped with 18 accelerometers and whose head trajectory during impact was determined by high-speed cine-photogrammetry. Moreover, mathematical simulation was applied to the problem utilizing an extended version of the CALSPAN CVS computer program.