Imagine a world where buildings are their own watchmen, aircraft twist themselves into optimal aerodynamic shapes and pipelines find and report their own leaks. On a limited -- and often experimental -- basis, that world is now. And, if a cadre of researchers working in locations across the globe have their way, that once improbable sounding scenario will become the way of the world.A propeller blade on the US Coast Guard icebreaker Polar Star wears an array of 54 Fabry-Perot fiber optic strain gauges. Courtesy of Fiso Technologies.Fiber optic sensors were embedded in a 20 x 50.5-m holography table at Switzerland's Institute of Material Mechanics to monitor the shrinkage over a three-year period. Courtesy of Smartec.With fiber optic sensors as the key, so-called Smart Structure projects are under way in such far flung places as the Pacific Rim, South Africa, Switzerland, France and the US. And its not just civil structures such as dams, bridges, mines and buildings that have caught the attention of the researchers. Items as varied as aircraft parts, automobile windshields, medical monitors and the next generation of space shuttles are fair game.The push to build a better smart structure is also accelerating fiber optic sensor technology. Fiber sensors come in many flavors and provide a broad spectrum of information. At one extreme a fiber sensor can simply confirm the presence or absence of light; at the other it can provide data in quantities that only a computer could love…