US Patent 11235875 Zone-based unmanned aerial vehicle landing systems and methods

Zone-based unmanned aerial vehicle landing systems and methods are provided herein. An example method includes establishing a plurality of operational zones, each of the plurality of operational zones being associated with a range of altitudes, guiding an unmanned aerial vehicle (UAV) through each of a plurality of operational zones to land the UAV on a target location using sensors, wherein the sensors are configured to sense a distance between the UAV to the target location, further wherein portions of the sensors are configured for use at different altitudes, and determining an error for the UAV during landing, wherein the UAV retreats to a higher altitude operational zone when the error is determined.