The aim of this paper is to report on the possible relationships between tramway front end geometry and pedestrian injury risk over a wide range of possible tramway shapes. Methods: To study the effect of tramway front-end shape on pedestrian injury metrics, accidents were simulated using a custom parametrized model of tramway front-end and pedestrian models available with the MADYMO multibody solver. The approach was automated, allowing the systematic exploration of tramway shapes in conjunction with four pedestrian sizes (e.g. 50 th percentile male or M50). Results: A total of 8,840 simulations were run, showing that the injury risk is more important for the head than for the other body regions (thorax and lower extremities). The head of the M50 impacted the windshield of the tramway in most of the configurations. Two antagonist mechanisms affecting impact velocity of the head and corresponding HIC values were observed. The first is a trunk rotation resulting from an engagement of the lower body that can contribute to an increase of the head velocity in the direction of the tram. The second is the loading of the shoulder that can accelerate the upper trunk and head away from the windshield, resulting in lower impact velocities. Groups of design were defined based on two main parameters (windshield height and offset), some of which seem more beneficial than others for tramway design. The pedestrian size and tramway velocity (30km/h vs. 20km/h) also affected the results. Conclusions: When considering only the frontend shape, the best strategy to limit the risk of head injury due to the contact with the stiff windshield seems to be to promote the mechanism involving shoulder loading. As body regions engaged vary with the pedestrian size, none of the groups of designs performed equally well for all pedestrian sizes. The best compromise seems achieved with a combination of a large windscreen offset and a high windscreen. Conversely, particularly unfavorable configurations are observed for low windshield heights, especially with a large offset. Beyond the frontend shape, considering the stiffness of the current windshields and the high injury risks predicted for 30km/h, the stiffness of the windshield should be considered in the future for further gains in pedestrian safety.

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The Open Source PIPER child scalable human body model was publicly released in April 2017 (www.piperproject.org) along with frontal and side impact validation conditions. The objective of this paper is to investigate the effect of anthropometry scaling on the response of the model in side pelvic impact. Three setups from two published studies were used: (1) a lateral drop test (2) a greater trochanter impact with a rigid pendulum (3) a pelvis side impact with a flat surface. The first study used scaling assumption developed for crash test dummy design (setups 1 and 2) and the second performed tests on post mortem human surrogates. The baseline 6 years old child model was scaled using a model morphing methodology to match the stature and weight of the surrogates used in the two published studies.Overall, the main trends observed in the three setups can be approached using the baseline model. Although the model morphing did not account for specific skeletal dimensions, it reduced some of the discrepancies between model response and reference for the drop test and flat plate impact. However, it had little effect on the pendulum test. In that case, the model response was in the corridor at low speed but above at higher speeds. Possible reasons for this difference should be further investigated.

This technical note focuses on the evaluation of a procedure for positioning a crash test dummy in a rail environment before physical testing. Through physical implementation, a simple approach consisting of adjusting the location of the dummy on the seat was evaluated and validated. The data collected was used to accurately align a virtual dummy with real-life information demonstrating that the procedure, coupled with virtual modelling, provides a powerful research tool by which to improve the passive safety of passengers travelling in rail vehicles.

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