The present disclosure is directed to controlling, reducing, and/or altering sound generated by an aerial vehicle, such as an unmanned aerial vehicle (UAV), while the aerial vehicle is airborne. For example, one or more transducers, such as piezoelectric thin-film transducers, or carbon nanotube transducers may be applied or incorporated into or on the surface of propeller blades that are used to aerially navigate the aerial vehicle. As the propeller blade rotates and generates sound, the transducers may be activated to generate one or more anti-sounds that cancel, reduce, or otherwise modify the sound generated by the rotation of the propeller blade. The anti-sound combines with the sound and causes interference such that the combined, or net-effect, is an overall cancellation, reduction, or other modification of the sound.

This invention discloses a flapping wing with multi film sheets listed on a net frame, wherein a fuselage is disposed on the flapping wing, transmissions are installed on both sides of the fuselage, a frame is installed on a side of each transmission, the frame is composed of supports and a fine net structure, one side edge of each film sheet is fixed on the fine net structure, and the other side edge of the film sheet can move freely; one end of a limit thread is connected with the fine net structure, while the other end of the limit thread is connected with the movable side edge of the film sheet. All the film sheets are arranged on the same side of the fine net structure.

Systems and associated methods for planning and control of a fleet of unmanned vehicles in missions that are coordinated temporally and spatially by geo-location, direction, vehicle orientation, altitude above sea level, and depth below sea level. The unmanned vehicles' transit routes may be fully autonomous, semi-autonomous, or under direct operator control using off board control systems. Means are provided for intervention and transit changes during mission execution. Means are provided to collect, centralize and analyze mission data collected on the set of participating unmanned vehicles.

An aerial vehicle or another system having moving components may be configured with a capacitive sensing system for detecting body parts of humans or other animals within proximity. The capacitive sensing system includes conductive components provided in association with surfaces of housings within which motors rotate propellers or other objects. The capacitors are coupled to circuits including transistors, resistors, capacitors or other features that are configured to determine levels of capacitance on the conductive components during operations of the aerial vehicle or other system. When a body part approaches a conductive component, and disrupts a level of capacitance on a capacitor coupled to the conductive component, a change in the level of capacitance on the capacitor is detected. Where the change exceeds a predetermined threshold, predetermined actions such as stopping or otherwise altering operations of the motors may be performed.

An aerial vehicle or another system having moving components may be configured with a capacitive sensing system for detecting body parts of humans or other animals within proximity. The capacitive sensing system includes conductive components provided in association with surfaces of housings within which motors rotate propellers or other objects. The capacitors are coupled to circuits including transistors, resistors, capacitors or other features that are configured to determine levels of capacitance on the conductive components during operations of the aerial vehicle or other system. When a body part approaches a conductive component, and disrupts a level of capacitance on a capacitor coupled to the conductive component, a change in the level of capacitance on the capacitor is detected. Where the change exceeds a predetermined threshold, predetermined actions such as stopping or otherwise altering operations of the motors may be performed.

Systems, methods, and devices for propelling self-propelled movable objects are provided. In one aspect, a rotor assembly for a self-propelled movable object comprises: a hub comprising a first fastening feature; a drive shaft comprising a second fastening feature and directly coupled to the hub by a mating connection of the first and second fastening features, wherein the drive shaft is configured to cause rotation of the hub such that the mating connection of the first and second fastening features is tightened by the rotation; and a plurality of rotor blades coupled to the hub and configured to rotate therewith to generate a propulsive force.

This disclosure describes a configuration of an unmanned aerial vehicle (UAV) that will facilitate extended flight duration. The UAV may have any number of lifting motors. For example, the UAV may include four lifting motors (also known as a quad-copter), eight lifting motors (also known as an octo-copter), etc. Likewise, to improve the efficiency of horizontal flight, the UAV also includes a pivot assembly that may rotate about an axis from a lifting position to a thrusting position. The pivot assembly may include two or more offset motors that generate a differential force that will cause the pivot assembly to rotate between the lifting position and the thrusting position without the need for any additional motors or gears.

This disclosure describes an unmanned aerial vehicle (UAV) and system that may perform one or more techniques for protecting objects from damage resulting from an unintended or uncontrolled impact by a UAV. As described herein, various implementations utilize a damage avoidance system that detects a risk of damage to an object caused by an impact from a UAV that has lost control and takes steps to reduce or eliminate that risk. For example, the damage avoidance system may detect that the UAV has lost power and/or is falling at a rapid rate of descent such that, upon impact, there is a risk of damage to an object with which the UAV may collide. Upon detecting the risk of damage and prior to impact, the damage avoidance system activates a damage avoidance system having one or more protection elements that work in concert to reduce or prevent damage to the object upon impact by the UAV.

Drones with propulsions systems supported in a housing are provided where the orientation of the housing is independent from the orientation of the propulsion system. Drones are provided where a propulsion system is rotatable about a first axis and a second axis that is perpendicular to the first axis, permitting the propulsion system to assume substantially any position with a sphere. Drones are provided where a bladeless inner tube is rotatable about a first axis and a second axis that is perpendicular to the first axis, permitting the inner tube to assume substantially any position within a sphere. Drone systems are provided with connectable unit drones. An unmanned land vehicle is provided having a wheel assembly that is rotatable about a first axis and a second axis that is perpendicular to the first axis, permitting the wheel assembly to assume substantially any position with a sphere.

An aerial craft and sealed force vectoring flight system is disclosed. The aerial craft includes a main body hull, lift jets, a generator, an electrical re-introduction circuit, a hydraulic pump, air flow compressors, an RPM sensor, a max speed limiter hydraulic draft by-pass valve, and a battery. The electrical re-introduction circuit throttles the generator into high-velocity rotation and yields excess electrical current to then be applied to the lift jets. The hydraulic pump pulls pressurized hydraulic fluid across a preceding hydraulic drive impellor such that the pressurized hydraulic fluid returns to confinement under pneumatic pressure faster than a discharge of hydraulic fluid. The air flow compressors generate electricity that is re-introduced into the lift electric motors. The RPM sensor and max speed limiter hydraulic draft by-pass valve speed regulate the generator. The battery initially powers the generator.