Smart Materials

Smart materials are one of the coolest new technologies out there right now, but they're hard to explain without actually seeing.  So if you go to about 4:00 into this video and watch for few seconds you'll see some smart materials in action and get a pretty good idea of how exciting they are for engineers.  The important part about the moving metal flaps in the demonstration is that those flaps are moving on their own and aren't being controlled by anything.  The way the heat from the sun effects the material they're made out of makes them curl up, so if they were placed on the outside of a skyscraper they would open on the sides of the building that were getting sunlight.  These new vents would let the building cool down easier from the heat that this sunlight would be adding, and means that skyscrapers with this kind of technology can stay cooler in hot summer months while using less electricity to power the massive air conditioning systems they need now.  Later in the video there's another part where she talks about making building walls open and close in the same way, so that the building could breathe itself naturally throughout the day and move air around to keep it cool without needing any power at all.

Another type of smart material that engineers can use in a lot of different places is conductive concrete.  This is just concrete with nanosized metal bits in the mix, but the metal content is set up in a way that lets the concrete conduct just a little bit of electricity.  This doesn't mean that the concrete will electrocute people who walk or drive on it, but the material can send small charges around to find faults in the concrete that would be caused by cracks or other weaknesses and defects long before they would be visible to human eyes or before they become a dangerous problem.  This would also mean that bridges, roads, and even building walls could be scanned for any areas that need to be repaired in a few seconds, which is a lot faster than the current way of walking very slowly around and looking very carefully at every inch of the surface to look for cracks and holes.  Another way that conductive concrete could be useful would be in designing safer roads for people to drive on in the rain or at night.  Usually in these times it can be hard to see the lines of the road, and sometimes the paint has faded off and is impossible to see.  But with electroluminescent materials a paint could used that lights up whenever a small current is run through it.  So by turning on the conductive concrete an entire highway or city could have roads with lanes that light up at night or in the rain to make it easier for drivers to see where they are going and help prevent accidents in these dangerous situations.