A plasma propulsion nozzle incorporates a cylinder having an inlet and an outlet. A plurality of substantially cylindrical planarly disbanded electrodes with sandwiched dielectric spacers is cascaded in an array to be concentrically expanding from the inlet through an interior chamber to the outlet for a nozzle. A voltage source applies aperiodic signal with rapidly reversing polarity to the electrodes with differential phase applied to adjacent electrodes in the array creating and expelling plasma clusters at each dielectric spacer inducing flow from the nozzle outlet to produce thrust.

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.

System and method can support a measurement module on a movable object. The measurement module includes a first circuit board with one or more sensors. Additionally, the measurement module includes a weight block assembly, wherein the weight block assembly is configured to have a mass that keeps an inherent frequency of the measurement module away from an operation frequency of the movable object. Furthermore, said first circuit board can be disposed in an inner chamber within the weight block assembly.

A sensor senses an attribute of a worksite at a location that is geographically spaced from a corresponding mobile machine. An operation is performed at the location, based upon the sensed attribute. An action signal is generated based on the effect data. An unmanned aerial vehicle communicates effect data, indicative of an effect of the operation at the location, to the mobile machine. The action signal can be used to control worksite operations.

An unmanned aerial device includes a body, a heat-generating assembly, and a propulsion assembly. The body has a head end, an airflow guide space, and a tail end. The head end is opposite to the tail end, and the airflow guide space is located between the head end and the tail end. The head end has an air intake, and the tail end has an exhaust vent. The airflow guide space is communicated with the air intake and the exhaust vent. The heat-generating assembly is disposed in the airflow guide space. The propulsion assembly is connected to the tail end, and the propulsion assembly is adapted to generate a propulsion airflow through the air intake, the heat-generating assembly, and the exhaust vent.

An unmanned aerial device includes a body, a heat-generating assembly, and a propulsion assembly. The body has a head end, an airflow guide space, and a tail end. The head end is opposite to the tail end, and the airflow guide space is located between the head end and the tail end. The head end has an air intake, and the tail end has an exhaust vent. The airflow guide space is communicated with the air intake and the exhaust vent. The heat-generating assembly is disposed in the airflow guide space. The propulsion assembly is connected to the tail end, and the propulsion assembly is adapted to generate a propulsion airflow through the air intake, the heat-generating assembly, and the exhaust vent.

A method and an apparatus for protecting an unmanned aerial vehicle and an unmanned aerial vehicle are provided. After a positioning system of the unmanned aerial vehicle fails, a flight speed of the unmanned aerial vehicle is acquired at a time point before the positioning system fails, and then a flight state of the unmanned aerial vehicle is determined according to the flight speed, where the flight state includes a low-speed flight state and a high-speed flight state; and then a flight protection strategy of the unmanned aerial vehicle is adjusted according to the flight state. By implementing the method, after the positioning system of the unmanned aerial vehicle is in failure, explosion probability of the unmanned aerial vehicle can be reduced, and flight safety of the unmanned aerial vehicle can be improved.

A method and an apparatus for protecting an unmanned aerial vehicle and an unmanned aerial vehicle are provided. After a positioning system of the unmanned aerial vehicle fails, a flight speed of the unmanned aerial vehicle is acquired at a time point before the positioning system fails, and then a flight state of the unmanned aerial vehicle is determined according to the flight speed, where the flight state includes a low-speed flight state and a high-speed flight state; and then a flight protection strategy of the unmanned aerial vehicle is adjusted according to the flight state. By implementing the method, after the positioning system of the unmanned aerial vehicle is in failure, explosion probability of the unmanned aerial vehicle can be reduced, and flight safety of the unmanned aerial vehicle can be improved.

A flight device that can accurately perform attitude control with a sub-rotor is provided. The flight device 10 includes an airframe 19, an engine 30, motors 21, main rotors 14, and sub-rotors 15. The engine 30 rotates the main rotors 14. The motors 21 rotate the sub-rotors 15. The main rotors 14 are arranged below the sub-rotors 15. In the flight device 10, arranging the main rotors 14 below the sub-rotors 15 prevents the sub-rotors 15 from being affected by an air flow generated by rotation of the main rotors 14. Accordingly, the sub-rotors 15 can provide thrusts as designed by being rotated, and the position and the attitude of the airframe 19 can be accurately adjusted.

A flight device that can accurately perform attitude control with a sub-rotor is provided. The flight device 10 includes an airframe 19, an engine 30, motors 21, main rotors 14, and sub-rotors 15. The engine 30 rotates the main rotors 14. The motors 21 rotate the sub-rotors 15. The main rotors 14 are arranged below the sub-rotors 15. In the flight device 10, arranging the main rotors 14 below the sub-rotors 15 prevents the sub-rotors 15 from being affected by an air flow generated by rotation of the main rotors 14. Accordingly, the sub-rotors 15 can provide thrusts as designed by being rotated, and the position and the attitude of the airframe 19 can be accurately adjusted.