Toyota filed a patent for an “autonomous fueling drone,” a wheeled vehicle loaded with gasoline or a battery charger, which would respond to motorists’ refueling requests on the road.
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After the request is wirelessly relayed via a dispatcher, the driverless tanker would navigate itself to the requesting vehicle with GPS/GNSS, and then use an unspecified set of other sensors to connect itself to the fuel tank or recharging port.
Since only a drawing is included with the application, it seems to be a concept patent, where Toyota stakes a claim to the idea rather than having a fleshed-out product.