Anti-personnel mines remain a global challenge with contaminated land estimated to be 300 km2 world-wide [1]. Annual casualty rates remain above 4,000 of which 42% are children [1]. Mine clearance operations typically utilize metal detectors to detect and locate buried mines through electromagnetic induction (EMI) of mine metallic components, followed by manual excavation to remove and disarm the threat [2]. Some anti-personnel mines have been designed to use the smallest amount of metal in their construction to impede their detectability. These types of mines are known as minimum metal mines and typically contain only a few metallic components limited to the necessary parts. Fig. 1 shows a cross-sectional schematic view of a typical anti-personnel mine with the metallic components highlighted in red, green and blue. While some anti-personnel mines can contain a spring and lock ball arrangement to form the detonation mechanism, highlighted in blue, minimum metal mines substitute these components and may utilize a non-metallic diaphragm to reduce their metallic content. As a result, minimum metal mines can contain metallic content that is composed of only a firing pin and the detonator casing, highlighted in red in Fig. 1. The safety pin is removed when arming the mine and so does not contribute to the EMI response measured by metal detectors.
Metallic content in anti-personnel mines. Figure adapted from [3].