Automotive · The edge of physics
Contraband Shadow — Concealed Metal Anomaly Imaging
Inside a metal vehicle, a small hidden metal object vanishes into the glare — physics says no.
We publish what we will not claim — that is how you can trust the rest.
Why the physics says no
Finding metal works by spotting an unusual reflection — but a vehicle body is one enormous metal reflector already. A small added object's echo drowns in that glare, especially with seats and passengers moving around. The idea is sound on paper and defeated in practice, so we retired it honestly.
In the physics: Metal is a near-perfect scatterer: a new metallic object creates strong specular paths (new CIR taps) and a high-sigma region in the reconstructed conductivity field. A vehicle's own metal structure is static, so any new persistent high-sigma voxel that isn't in the baseline map is anomalous by construction.
Reviewer's verdict: The vehicle is itself a large metal enclosure dominating scattering; a small added metal object's contribution against that metal-cabin background, amid seat/occupant reconfiguration, is below practical detectability. Differencing is valid in principle but defeated by the background.