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The Flexible Pedestrian Legform Impactor (Flex-PLI) was developed to evaluate the risk of pedestrian lower extremity injuries. However, it has been pointed out that the post-crash kinematics of the Flex-PLI differs from those of a human body when it is hit by high-bumper vehicles. This paper describes the feasibility of applying the Flex-PLI to a wide range of vehicle types by adding a supplemental weight. The following aspects are discussed in this regard: A human body finite element (FE) model analysis shows that the upper body of the Flex-PLI is not involved in tibia and knee ligament injury indexes in the first contact with a high-bumper vehicle. A rigid bar model is introduced and its rotational energy ratio is formulated. The rotational energy ratio is employed to evaluate the post-crash kinematics of the Flex-PLI and a human leg model. The feasibility of adding a supplemental weight to the Flex-PLI with regard to the bumper height is discussed.

This study focused on European NCAP activities of introducing a new head protection evaluation procedure, as proposed by BASt (Federal Highway Research Institute - GERMANY). Various kinds of E-bikes are available in the market, ranging from E-bikes that have a small motor to assist the rider’s pedal-power i.e., pedelecs to somewhat more powerful E-bikes which is similar to a moped-style scooter. This paper focused on identifying the factors influencing bicyclist head kinematics during bicycle vs. passenger vehicle (PV) collisions at the intersection. Two AM50 bicyclist FE models are developed using i) GHBMC Human Body Model (HBM) and ii) WorldSID (WS) side impact dummy. Head kinematics of bicyclists of pedal-assist E-bike and normal bike were compared using CAE simulation. It is found that the vehicle’s impact velocity, type of bicycle, the mass of E-bike and bicycle traveling speed will influence the head kinematics.

With SUVs and minivans accounting for a larger share of the US market in the past decade, rollover accidents have drawn greater attention, leading to more active research from different perspectives. This ranges from investigations for elucidating the basic causes and mechanisms of rollover accidents to studies of more advanced occupant protection measures. As the phenomenon of a rollover accident is longer in duration than frontal, side or rear impacts, it is relatively difficult [1] to simulate such accidents for experimental verification and also for proper evaluation of occupant restraint system performance. In this work, we focused on the trip-over type, which occurs most frequently, and performed simulations to reproduce real-world rollover accidents by combining PC-Crash and FEA. Soil trip-over simulation was carried out based on real world accidents.

With SUVs and minivans accounting for a larger share of the US market in the past decade, rollover accidents have drawn greater attention, leading to more active research from different perspectives. This ranges from investigations for elucidating the basic causes and mechanisms of rollover accidents to studies of more advanced occupant protection measures. As the phenomenon of a rollover accident is longer in duration than frontal, side or rear impacts, it is relatively difficult [1] to simulate such accidents for experimental verification and also for proper evaluation of occupant restraint system performance. In this work, we focused on the trip-over type, which occurs most frequently, and performed simulations to reproduce real-world rollover accidents by combining PC-Crash and FEA.

Incompatibility between two colliding cars is becoming an important issue in passive safety engineering. Among various phenomena, indicating signs of incompatibility, over-riding and under-riding are likely caused by geometrical incompatibility in vertical direction. The issue of over-riding and under-riding is, therefore, not only a problem for partner-protection but also a possible disadvantage in self-protection. One of the possible solutions of this dual contradictory problem is to have a good structural interaction between the front-ends of two cars. Studies have been done to develop a test protocol for assessment of this interaction and to define criteria for evaluation but mostly in terms of aggressivity, which is a term describing incompatibility of a relatively stronger car. In this study, it was hypothesized that homogeneous front-end could be a possible better solution for good structural interaction.

In side-crash phenomena, finite element modeling is essential in investigating the occupant's post-impact dynamic behavior after contact with the door panels. A number of modifications have been made to the model described here based on combined simulation and experimental verifications of the dynamic and pseudo-static characteristics of different materials such as foam, damper and individual sub-assemblies. This report illustrates how the modified material and structural modeling of different components improve the accuracy of the overall dynamic behavior of the FEM model in simulating different HYGE experiments to speed up and optimize the vehicle design process. The rib-module drop test results with two different polypropylene pads clearly indicate the effect of the pad unloading characteristics on rib displacement.

A comprehensive analysis was performed to evaluate the effect of BMI on different body region injuries for side impact. The accident data for this study was taken from the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS). It was found that the mean BMI values for driver and front passengers increases over the years in the US. To study the effect of BMI, the range was divided into three groups: Thin (BMI<21), Normal (BMI 24-27) and Obese (BMI>30). Other important variables considered for this study were model year (MY1995-99 for old vehicles & MY2000-08 for newer vehicles), impact location (side-front F, side-center P & side-distributed Y) and direction of force (8-10 o'clock for nearside & 2-4 o'clock for far-side). Accident cases involving older occupants above 60 years was omitted in order to minimize the bone strength depreciation effect. Results of the present study indicated that the Model Year has influence on lower extremity injuries.

A logistic regression analysis of accident cases in the NASS-PCDS (National Automotive Sampling System-Pedestrian Crash Data Study) database clearly shows that pedestrian pelvis injuries tend to be complex and depend on various factors such as the impact speed, the ratio of the pedestrian height to that of the bonnet leading edge (BLE) of the striking vehicle, and the gender and age of the pedestrian. Adult female models (50th %ile female AF50: 161 cm and 61 kg; 5th %ile female AF05: 154 cm and 50 kg) were developed by morphing the JAMA 50th %ile male AM50 and substituting the pelvis of the GHBMC AM50 model. The fine-meshed pelvis model thus obtained is capable of predicting pelvis fractures. Simulations conducted with these models indicate that the characteristics of pelvis injury patterns in male and female pedestrians are influenced by the hip/BLE height ratio and to some extent by the pelvis bone shape.