US Patent 10120376 Renewable UAV energy via blade rotation

A computer-implemented method includes: monitoring, by a computer device, a charge level of a battery of an unmanned aerial vehicle (UAV); determining, by the computer device and based on the monitoring, the charge level is less than a threshold level; docking the UAV on a host vehicle; charging the battery using wind-induced rotation of a rotor of the UAV while the UAV is docked on the host vehicle; determining, by the computer device, the UAV is moving away from a destination while the UAV is docked on the host vehicle; and undocking the UAV from the host vehicle based on the determining the UAV is moving away from the destination.