Autonomous cars stir up plenty of emotions in drivers. Some folks lament the fact that their children and grandchildren will never know the joys of driving. (Future children and grandchildren stuck in traffic jams may not feel the same way.)  Others are excited by autonomous tech and the promise of reduced accidents, fatalities, and insurance rates. (They will probably be less excited by the technology's price tag.) But even those who despise the idea of autonomous passenger vehicles may appreciate the idea of self-driving big rigs. If you're in that number, you'll be interested to know that Daimler and its subsidiary, Mercedes-Benz, have tested an autonomous 18-wheeler in real highway traffic. Check out the video here -->>  https://youtu.be/ASaDg3dOalg WHY BIG RIGS? Big rigs are a vital part of the global economy, shipping our TVs, our smartphones, and, of course, more than a little food. But they're not ideal. Tractor-trailers are big, they're ungainly, and to make ends meet, many drivers put in long, tiring hours behind the wheel. A potentially drowsy driver maneuvering tons of lumbering metal down a highway with far smaller cars can be a recipe for disaster -- and not just for other vehicles. In 2013, some 62 percent of large-truck fatalities involved a single vehicle (i.e. the big rig itself). Numerous technologies on the market or in the works promise to make big rigs safer. There are devices to detect drowsy driving, others that make trailers "see-through", and the federal government has even proposed installing speed limiters to keep 18-wheelers from zipping down highways. (Though that could just make for more monotonous, sleep-inducing driving.) The biggest advance in big rig safety, however, may come via autonomous technology. In fact, 18-wheelers could easily become the leaders of the self-driving revolution. Why? As we've discussed before, humans can't drive better than autonomous cars -- or autonomous 18-wheelers, for that matter. We might like to think we're superior to a bunch of silicon chips, but real-world stats suggest that we're way off base. Remember: all 11 accidents in which Google's autonomous test fleet have been involved have been due to human drivers.  Autonomous tech could be of significant benefit to professional drivers. A recent study conducted by Daimler's truck division demonstrated "that driver fatigue decreases by 25 percent if they are relieved of monotonous lane-keeping and can focus on other tasks". (Obviously, Daimler has an interest in proving that its technology is important and desirable, so take that study with a bit of skepticism, if you like.) Autonomous tech could be of real benefit to trucking companies. Allowing a computer to shift gears, accelerate, and brake on its own can save around five percent in annual fuel costs compared to human drivers.  The technology can be added to existing vehicles. For the test drive in the video above, Daimler installed its Highway Pilot system on a standard Mercedes-Benz Actros. That could speed up adoption of autonomous tech, since it will allow trucking firms to upgrade existing vehicles instead of shelling out for brand-new ones. The public may be more accepting of autonomous technology on big rigs because it bears many similarities to commercial technology that everyone already knows -- namely, the airplane autopilot. As Daimler explains, its self-driving system is more "semi-autonomous" than fully autonomous, requiring the presence of a human monitor, just as modern airplanes do.   Due to those and other factors, autonomous big rigs could help speed up the adoption of self-driving technology among other drivers. That's not just because people will become used to the idea of autonomous vehicles. It's also because autonomous vehicles could help with the roll-out of highway based autonomous car systems, like Volvo's SARTRE. Daimler hasn't indicated when it will make this autonomous technology available to trucking companies and independent operators. Obviously, there are plenty of legal hoops to jump through before that can happen, but rest assured: it's going to happen.