Amazon foldable-wing drone
A diagram shows Amazon’s foldable-wing drone in its configuration for takeoff and landing. (Amazon Illustration via USPTO)

Amazon has sought patents for hitchhiking drones, mini-drones that can sit on shoulders, drones that assemble themselves like Lego toys – and now drones that flip their wings to go from vertical to horizontal flight.

The hybrid foldable-wing design is covered in a patent that was published on Tuesday, following up on an application filed back in 2014.

When the drone takes off, the robo-plane’s jointed wings would be folded around to provide a stable base for a vertical takeoff, with the rotors spinning in a horizontal plane.

But once the drone gets up in the air, the wings and tail would stretch out to create an airplane-style configuration. The rotors would then be spinning in a vertical plane, like a traditional airplane’s propellers, to push the drone forward.

When it’s time to land, the drone’s wings and tail would fold up again for a vertical landing. In their filing, Amazon’s inventors compare the craft to a Bell Boeing V-22 Osprey military aircraft, which tilts its rotors from vertical to horizontal, depending on whether it’s taking off or moving ahead.

Foldable-wing drone flight profile
This diagram illustrates how the foldable-wing drone transitions from takeoff to horizontal flight, and then to landing. (Amazon Illustration via USPTO)
Folded and straight wings
Here’s one view of the drone transformation from straight-wing to folded-wing configuration. (Amazon Illustration via USPTO)
Amazon drone configurations
These diagrams show how the same drone can look quite different in folded-up vs. unfolded-wing configurations. (Amazon Illustration via USPTO)

The system could be well-suited for Amazon’s delivery drones, which have to lift off with packages weighing up to 5 pounds and then fly away horizontally at speeds of up to 50 mph to make deliveries within a half-hour.

But just because it’s patented doesn’t mean that Amazon will follow through with this particular design. The Seattle-based retail giant traditionally doesn’t comment on its patent strategies; however, Amazon has said there’s likely to be different types of drone designs for different environments.

The type of drone that made the first commercial Amazon deliveries in England last month looks more like a traditional quadcopter, while the test drone that made its debut in 2015 has vertical as well as horizontal rotors.

Will future Amazon videos show off wing-flipping Transformer drones, or self-assembling Borg drones? Watch the skies…

Jeff Bezos, inventor

Yet another Amazon patent published on Tuesday covers a system for determining the center of gravity for a payload that’s put on a delivery drone, and then making adjustments so that the craft is optimally balanced when it takes off.

The processing system could shift the position of the payload on the drone’s carrier, just to make sure it’s stable. It could even judge whether the contents of a package might shift around too much during flight. If so, the payload could be automatically flagged for repackaging or for an alternate delivery method.

One of the most notable things about this patent application, filed in 2014, is the list of inventors. The lineup includes Jeff Bezos, Amazon’s billionaire founder, as well as Prime Air VP Gur Kimchi.

Motor arms
This diagram shows how a set of motor arms on a drone (labeled as 205) could be extended or retracted to adjust for a payload’s center of gravity. (Amazon Illustration via USPTO)

Still more patents published this week address procedures to recharge a drone’s batteries in flight by taking advantage of wind power or other types of airflow, and an autonomous delivery transportation network.

If nothing else, the flood of patents demonstrates that Amazon is taking innovation in delivery systems very, very seriously.

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