A door lock is a silent witness that records every access attempt. The scratches on its surface, far from being collateral damage, form a physical record of force, tool, and technique. In the 3D forensic pipeline, this micro-relief becomes an evidence map that allows reconstructing the mechanics of the forced entry and distinguishing an accident from a deliberate intrusion.
Photogrammetry and structured light for micro-analysis 🔍
The technical process begins with high-resolution capture using close-range photogrammetry, combined with structured light scanning to resolve grooves smaller than 50 microns. The alignment software generates a dense mesh that is compared against a reference CAD model of the original lock. Surface difference algorithms isolate the marks, calculating their depth, direction vector, and angle of incidence. This quantitative analysis allows classifying the scratches by tool type (lock pick, drill, master key) and estimating the sequence of attempts on the cylinder.
The CSI of the door: when your lock cylinder needs expert analysis 🚪
After hours of scanning the cylinder, one discovers that most scratches were not made by a burglar, but by the owner with their key copied at the corner kiosk. The forensic pipeline is so precise that it can distinguish between a professional forced entry and the clumsiness of someone trying to open the door with their car key. In the end, the technical report concludes: the lock was not forced, only mistreated by its owner. Next time, get a copy made at a real locksmith.