2 . One billion people in the world are short of water. How can this problem be solved. Some suggestions have been to desalinate ocean water or to build enormous water pipelines from areas where water is abundant. (Suggestions such as these prove extremely expensive when they are actually used.) One possibility that scientists are considering is pulling icebergs from either the North Pole or the South Pole to parts of the world with a water shortage. Although many questions must be answered before such a project could be tried, moving icebergs seems a reasonable possibility in the future.

Engineers, mathematicians, and glaciologists from a dozen countries have been considering the iceberg as a future source of water. Saudi Arabia is particularly interested in this project because it has a great water shortage. Scientists estimate that it would take 128 days to transport a large iceberg (about 1/2 square mile) to Saudi Arabia. Yet the iceberg would be completely melted by the 104th day. Therefore, insulation would be essential, but how to insulate the iceberg remains an unsolved problem.

The problems in transporting an iceberg are numerous. The first problem is choosing the iceberg to pull. The icebergs that form in the North Pole are quite difficult to handle because of their shape. Only a small portion extends above the water — most of the iceberg is below the surface, which would make it difficult to pull. South Pole icebergs, on the other hand, are flat and float like table tops. Thus they would be much easier to move.

How can a 200-million-ton iceberg be moved. No ship is strong enough to pull such enormous weight through the water. Perhaps several ships could be used. Attaching ropes to an iceberg this size is also an enormous problem. Engineers think that large nails or long metal rods could be driven into the ice. What would happen if the iceberg splits into several pieces during the pulling. Even if an iceberg with very few cracks were chosen, how could it be pulled through stormy waters. Furthermore, once the iceberg reached its destination, very few ports would be deep enough to store it.

All of these problems must be solved before icebergs can become a reasonable source of water. Yet scientists estimate that it will be possible to transport them in the near future. Each year, enough icebergs form to supply the whole world with fresh water for a full year. In addition, icebergs are free and nonpolluting. As a solution to the world’s water problems, icebergs may be a workable possibility.

3 . A robot with a sense of touch may one day feel “pain”, both its own physical pain and sympathy for the pain of its human companions. Such touchy-feely robots are still far off, but advances in robotic touch-sensing are bringing that possibility closer to reality.

Sensors set in soft, artificial skin that can detect both a gentle touch and a painful strike have been hooked up to a robot that can then signal emotions, Asada reported February 15 at the annual meeting of the American Association for the Advancement of Science. This artificial “pain nervous system,” as Asada calls it, may be a small building block for a machine that could ultimately experience pain. Such a feeling might also allow a robot to “sympathize” with a human companion’s suffering.

Asada, an engineer at Osaka University, and his colleagues have designed touch sensors that reliably pick up a range of touches. In a robot system named Affetto, a realistic looking child’s head, these touch and pain signals can be converted to emotional facial expressions.

A touch-sensitive, soft material, as opposed to a rigid metal surface, allows richer interactions between a machine and the world, says neuroscientist Kingson Man of the University of Southern California. Artificial skin “allows the possibility of engagement in truly intelligent ways”.

Such a system, Asada says, might ultimately lead to robots that can recognize the pain of others, a valuable skill for robots designed to help care for people in need, the elderly, for instance.

But there is an important distinction between a robot that responds in a predictable way to a painful strike and a robot that’s able to compute an internal feeling accurately, says Damasio, a neuroscientist also at the University of Southern California. A robot with sensors that can detect touch and pain is “along the lines of having a robot, for example, that smiles when you talk to it,” Damasio says. ‘It’s a device for communication of the machine to a human.” While that’s an interesting development, “it’s not the same thing” as a robot designed to compute some sort of internal experience, he says.