If they get hit by a high calibre bullet, it will tell the medical teams how much blood they are losing. Even in the dark or the smoke of battle, the medics will find them, because they will be on their screens too - linked to a global positioning system that can pinpoint them to a metre or two. For five years, that has been the dream. A US team of engineers may be about to change that. Researchers at the Pacific Northwest National Laboratory in Washington state have just unveiled a space age generator that weighs less than 2lb, measures little more than a fat paperback novel, can generate 25 watts and keep going for a week.
Fuel cells powered by hydrogen are the power packs of tomorrow.
Although invented by a Victorian barrister called William Grove, they were first used to get Apollo astronauts to the moon. Smaller scale fuel cells are already on trial in buses in Chicago. The latest design from the Washington labs will contain a store for aviation spirit or diesel to make the hydrogen, a cell in which the hydrogen reacts with oxygen to yield energy, and a little lithium battery, all in tubes about eight inches long. The complete system could be ready for testing by 2003. It all takes power, but we can't ask these soldiers to carry any more weight.