Source: http://arstechnica.com/cars/2015/05/...driving-truck/
Last night, on the Hoover Dam, Freightliner (which is owned by automotive giant Daimler) unveiled the first road-legal self-driving truck. At the event last night, the Inspiration Truck (yes really) was awarded an official autonomous vehicle license plate by the governor of Nevada.
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The lorry has the same "NHTSA Level 3" rating as Google's self-driving car, which means that it's fully autonomous, but that the driver still has to be able to take over "with sufficiently comfortable transition time" if the need arises. In this case, while the Inspiration Truck could drive itself for hundreds of miles without driver intervention, Daimler is framing this as a conversation around driver fatigue. According to Daimler, 90 percent of truck crashes are due to driver error, and driver fatigue plays a role in 1/8th of those crashes.
Wolfgang Bernhard, head of Daimler's truck company, said at the event last night that the company tested driver brain activity with and without the autonomous driving system enabled. With the system turned on, "driver drowsiness decreases by about 25 percent."