The Invisible Danger

With about 100 million having been planted in 70 countries, landmines pose a continuous threat to life and limb. There are more than 20,000 casualties each year.

Nobody knows exactly how many there are or where they are. They remain an invisible danger with the main victims often being children playing or wandering off the beaten track.

Although many nations around the world have signed a treaty banning their future use, it will be many years before the existing mines are cleared. In fact, at the current rate of funding, it could
take hundreds of years.

The roll-out of mine clearance programmes is limited by cost. Available mine-detectors are expensive and there is a shortage of highly trained operators. Even if there were to be a massive increase
in funding, lack of operators would still prevent a speeding up of the programme.

As part of an internally funded programme aimed at humanitarian needs Chris Richardson, principal consultant at Roke Manor Research (RMR), has developed a prototype motion-powered mine detector.

It addresses the developing countries' need for a simple device with low running costs that can be operated with minimal training.

The detector is used in the conventional manner with the operator "sweeping'' it over the ground at the same time as listening for the audio tone in the earphones that indicates that an anomaly has
been encountered.

Providing the power for any electrical device is always a problem. Batteries run out unpredictably and, especially in developing countries, often have to be imported. They are expensive and are thus
a drain on limited resources.

Solar power, while clearly appropriate for many countries because there are no continuous costs, cannot be used in forest areas where there is tree cover.

Mr Richardson has overcome the problem of providing electrical power by using the kinetic energy that results from the motion of sweeping the detector above the ground to generate the necessary
power.

After a few initial swings of the mine detector, enough power has been generated and it can be put to work. As users continue the sweeps, the motion maintains the electrical power so enabling the
detector to carry on working.

While the demonstrator has been configured to measure permeability · mainly for the detection of mines containing some metal · a similar system is under development that measures the permittivity and
resistivity.

This has been found to be effective in detecting both metal and plastic mines. Good discrimination between plastic mines and other non-metallic objects is possible.

While this technology does not yet achieve the very high levels of "false-alarm'' rejection potentially offered by today's more complex technologies, it is far cheaper both to build and to operate.

Were every village in war-torn areas to have their own mine detectors, with villagers being trained in their use, the people would be able to institute and run their own mine-clearance programmes.

As they would only be working around their own village they would only have to recognise the particular types of mines which had been sown in that area and to be able to differentiate them from the
background terrain.

Samstag, 28. November 1998 00:00:00
Update: Dienstag, 01. März 2005 16:52:00