Abstract :
Imagine it\´s Christmas morning and the kids are tearing open their presents. Through the blizzard of shredded wrapper, one gift in particular catches your eye a robot or flying toy, say, its box emblazoned with exhortations to amaze your friends. "Hmm," you think, "I wouldn\´t mind having a go of that myself." It\´s a refrain that must date at least from the advent of model train sets. Toy technology particularly control has long fascinated kids of all ages, and these days, as its cost falls in seemingly inverse proportion to its functionality, you can get a lot of it for your money. Also, as with model trains, for example, some of the latest gizmos can form not only the basis of an abiding hobby but also the starting point for developing systems of your own.