The three-dimensional recreation of an urban accident between a tram and a scooter has allowed forensic investigators to determine that the light vehicle remained hidden in a structural blind spot of the convoy. The simulation, validated with data from the real scene, demonstrates that the scooter's trajectory and the tram's design made its timely detection impossible, absolving the driver of direct responsibility.
Technical workflow: from point cloud to dynamic simulation 🛠️
The process began with laser scanning of the scene using Faro Scene, generating a georeferenced point cloud that captured the exact geometry of the track, the tram, and the surface damage. This model was imported into AutoCAD to clean the mesh and create a clean 3D environment. Subsequently, in Blender, the scooter was modeled with millimeter precision and textured to reflect the lighting conditions at the time of the incident. The core of the analysis was performed in PC-Crash, where friction coefficients, masses, and estimated speeds were input. The simulation reproduced the impact dynamics, validating that the scooter was in the blind spot generated by the tram's front pillar during the turn, a point the driver could not see from their cabin.
Forensic implications and urban design 🚦
The recreation not only clarified the mechanics of the accident but also exposed a weakness in the tram's design. The combination of the scooter's approach angle and the width of the front pillar created an invisibility zone that no mirror could cover. This finding forces a rethinking of safety protocols at intersections with tram tracks, suggesting the installation of peripheral sensors or convex mirrors on the pillars to eliminate these fatal blind spots.
How does the 3D reconstruction of the tram-scooter accident reveal the influence of the blind spot on risk perception and the driver's decision-making during the evasive maneuver?
(PS: In scene analysis, every scale witness is a small anonymous hero.)