Experiments on scale reduction in infrared landmine detection

A method has been proposed to reproduce in the laboratory the heating and cooling cycles of a soil with a buried land-mine. The method allows the length-scale and time-scale of the experiments to be drastically decreased. This is achieved by dimensional analysis of the thermal problem. A preliminary confirmation of the used approach was obtained with simplified tests [1-3].In the present work, the method is verified experimentally. Models of different types of land-mine are produced for this purpose. Full-scale and scaled-down models are built by a rapid prototyping technique, using materials with thermal properties similar to those of the actual land-mines.The response of the soil surface is monitored during the thermal cycles by an infrared camera. Preliminarily, the surface response measured above full-scale models is cross-checked against that measured above actual land-mines. Full-scale and scaled-down models are then tested outdoors and in the laboratory, respectively. The measured distribution and time-evolution patterns of surface temperature are eventually compared, in order to assess the reliability of the scale reduction method.