Improvements of a tram shape for pedestrian protection

In this paper, a three-dimensional collision between a city tram and a pedestrian is simulated based on the finite element method (FEM). From the point of view of pedestrian protection, two principles are proposed for the geometry design of the city tram front end. Firstly, the front end structure should be designed to reduce the pedestrian injury severity. Secondly, after the collision the front end structure should push the pedestrian away from the city tram's running zone so as to avoid the run over. Based on these principles, four key parameters for the optimisation of the front end geometry are proposed, such as the clearance between the city tram and ground, the horizontal and vertical inclination angles of the streamline and whether there is any convex/concave structure. According to the simulation results, the influences of these parameters on the collided pedestrian's moving posture and injury severity are comprehensively analysed. In order to reduce the pedestrian injury, the recommended values for each design parameter are also proposed.