Introduction:

Instead of converting the information given by the induction coil sensor, used in
conventional metal detectors, to an audio signal, it is possible to use it for imaging
purposes. By moving the sensor and displaying data using different colors for different response amplitudes a map of the metal content in the soil can be constructed.
 

Research studies:

• The ODIS project at DASA-Dornier has demonstrated encouraging results in the detection of unexploded ordnance. In its current version it is able to detect metal parts of less than 1cm3. Penetration depth is about 50cm.

Using appropriate software, the system is able to compute the magnetic center of an object (±2cm), its depth (±10%) and its metallic volume. The phase information is used to determine the type of metal.
Currently the system is only able to differentiate between ferromagnetic and non-ferromagnetic material, but an amelioration of the phase measurement could allow a better metal determination.
The current prototype is quite heavy, but a study has demonstrated the feasibility of a man portable system.