A fire truck with an articulated ladder struck a high-voltage cable during a rescue maneuver. To determine whether the accident was due to a height sensor error or a failure in the collision prevention system's logic, a 3D forensic reconstruction was performed. The analysis combined telemetry data, physical deformations of the pistons, and kinematic modeling to recreate the exact trajectory of the articulated arm.
Forensic workflow: from sensor data to simulation in Unreal Engine 5 🛠️
The process began with extracting the height and angle records from the position sensor, which were imported into PC-Crash to calculate the theoretical trajectory of the ladder. Simultaneously, the actual deformations of the hydraulic pistons were scanned in Faro Zone 3D to generate a point cloud of the damaged geometry. With this data, the articulated ladder was modeled in SolidWorks, adjusting the stiffness and articulation parameters. Finally, the complete scene was recreated in Unreal Engine 5, overlaying the kinematic simulation of the prevention system with the actual deformation, revealing an angular discrepancy of 4.2 degrees between the sensor reading and the physical position of the arm.
The technical lesson: reliable sensors do not guarantee safe logic ⚠️
The reconstruction showed that the height sensor was functioning correctly, but the collision prevention system's logic ignored the actual position of the high-voltage cable by not integrating the elastic deformation of the pistons under load. The error was not in the hardware, but in the algorithm that assumed perfect rigidity. This case underscores the need to validate simulation models with actual deformation data, especially in rescue equipment where a logic failure can have fatal consequences.
What 3D reconstruction methodology do you recommend for accurately modeling the impact angle between the articulated ladder and the high-voltage cable, considering the limitations of sensor lighting and occlusion in a nighttime emergency scene?
(PS: In scene analysis, every scale witness is a little anonymous hero.)