Combination of GPR and metal detector for mine detection

This paper reports the progress of a three-year project with the objective to demonstrate multisensor techniques for mine surveillance. Data fusion techniques are using ground penetrating radar (GPR) of type ERA and a metal detector (MD) with induction coil of type Schiebel. The integration with a biosensor has been postponed until further technical development. The data fusion process runs in three main steps. First all sensor reports are converted to likelihood´s according to type. The likelihood´s are based on a priori test measurements with buried objects of different materials and sizes (low metal content mine, metal shrapnel, wax, stone, sand). In the second step the joint sensor report during a given time period, e.g. one measurement with MD/GPR, is computed as a product of probabilities. Finally, nearby measurement points are updated along the scanning MD/GPR system using a Bayesian fusing method. Compared with single sensors, the two-sensor system results in enhanced probability of detecting an object with both metal content and a surrounding shell of contrasting material, e.g. a low-metal content anti-personnel mine. At the same time the false alarm rate is significantly lowered