If the idea of a drone flying into your backyard and setting down a package from Amazon.com strikes you as something out of “The Jetsons,” how about this alternative. A self-driving car arrives outside your house and a robot rolls out and delivers a package to your front door.

As fantastical as either concept might seem, they’re on the drawing boards of various companies. People in both the self-driving car and pilotless drone industries are debating how they can remake the delivery of physical goods to homes and businesses. They have some time: Both cars and drones face technical and regulatory barriers that will delay large-scale testing and use in package delivery for several years. When it comes to those regulations, cars may have an edge.