Amazon is working on self-driving cars, according to a new patent that deals with the complex task of navigating reversible lanes. From a report on The Guardian: The patent, filed in November 2015 and granted on Tuesday, covers the problem of how to deal with reversible lanes, which change direction depending on the bulk of the traffic flow. This type of lane is typically used to manage commuter traffic into and out of cities, particularly in the US. Autonomous vehicles, the patent warns, "may not have information about reversible lanes when approaching a portion of a roadway that has reversible lane", leading to a worst-case scenario of them driving headfirst into oncoming traffic. More generally, the inability to plan for reversible lanes means cars and trucks can't optimize their routes by getting into the correct lane well in advance, something that could otherwise prove to be one of the benefits of self-driving cars. Amazon's solution to the problem could have much larger ramifications than simply dealing with highway traffic in large cities. The patent proposes a centralized roadway management system that can communicate with multiple self-driving cars to exchange information and coordinate vehicle movement at a large scale.