930 results about "Flight formation" patented technology

An autonomous formation flying sensor for precise autonomous determination and control of the relative position and attitude for a formation of moving objects.

A display presents to the viewer the outputs of a dual mode Traffic Collision Avoidance System (TCAS)/Intra-Formation Position Collision Avoidance System (IFPCAS). IFPCAS requires the cooperation of a least two formation follower aircraft in conjunction with the formation lead aircraft. The display indicates the relative velocity of the other formation follower aircraft, with respect to the formation lead aircraft, in addition to other types of information.

A flightpath guidance system and method is disclosed for using moving waypoints for a curved route plan such as a Bezier curve. The actual location of a vehicle and a leading target point along the path are used to provide commanded guidance of the vehicle along the path and to correct for disturbances from the intended route. Waypoints along the path may be moving with respect to the reference frame in which the vehicle is measured. Curved flightpath guidance using moving waypoints may be used for aerial rendezvous and refueling, multiple vehicle applications such as formation flying and battlefield formation grouping, and carrier landing. Further application includes air traffic control and commercial flight guidance systems.

A system for autonomously keeping an aircraft's station in a formation flight of a plurality of aircraft includes a navigation system configured to determine a position of an aircraft. A data link is configured to allow the aircraft to communicate data with at least one other aircraft in the formation flight of the plurality of aircraft. A sensor is configured to detect a presence of another aircraft within a predetermined distance of the aircraft. A processor is configured to provide control signals to the aircraft's autoflight system to keep the aircraft at a predetermined station relative to the other of the plurality of aircraft in the formation flight.

Method and apparatus for providing real-time data indicative of the isotopic composition of formation fluids during drilling. The method includes the steps of: (a) providing a reference fluid having a known isotopic composition in a reference cell; (b) capturing a sample of formation; (c) providing at least one laser beam; (e) passing a beam through the reference fluid, measuring the reference-measurement beam before and after it passes through the reference fluid; (f) and passing a beam through the sample, measuring the beam before and after it passes through the sample, and calculating a first isotope concentration from those measurements. The measurements can provide information relating to the carbon isotopic composition of individual compounds in hydrocarbon gas mixtures, with the individual compounds including methane, ethane, propane, iso- or normal butane, or iso- or normal pentane.

The invention discloses a collaborative flight path intelligent planning method for formation flying of unmanned planes under a dynamic environment. The method comprises the steps of offline intelligent planning of a formation pre-flying collaborative flight path of the unmanned planes, online replanning of the flight path for avoiding threats, collaborative rebuilding of a formation team and the like. The offline intelligent planning of the formation pre-flying collaborative flight path of the unmanned planes adopts an intelligent planning method based on a Voronoi graph and an ant colony algorithm, and an integrated optimal pre-flying flight path with collaborative time can be planned off line for the unmanned plane. The replanning of the online flight path adopts an intelligent flight path planning method based on an RRT (Rail Rapid Transit) algorithm, and quick flight path correction can be provided when the unmanned plane formation meets a sudden threat. The collaborative rebuilding of the formation team adopts a method combining unmanned plane formation member flying speed adjustment and coiling maneuvering. According to the method, pre-flying collaborative flight path offline planning and generation of online replanned flight path are provided for the unmanned plane formation, a collaborative rebuilding scheme is provided, and the online rebuilding problem of unmanned plane formation flying cooperativity is solved.

The invention relates to a method for cooperative search and dynamic task allocation of unmanned aerial vehicle teams under an uncertain environment, and not only puts forward a cooperative dynamic task allocation strategy of unmanned aerial vehicle teams, but also designs a concrete guidance law. By adopting an arc air route as the air route by which unmanned aerial vehicles performing tasks, the method includes: step 1. determining the data structure of single unmanned aerial vehicle maintenance; step 2. determining the flight mode of unmanned aerial vehicles; step 3. determining the dominant function of task performing of the unmanned aerial vehicles; step 4. determining a dynamic task allocation process; and step 5. determining the guidance law of aerial vehicle search and task performing. Compared with modern optimization algorithm based task allocation methods, the method provided in the invention reduces the computation load of single unmanned aerial vehicle, and is suitable for conditions characterized by strong real-time performance and uncertain environment. Compared with market mechanism auction algorithm based task allocation methods, the method reduces the times of communication performed among unmanned aerial vehicles and the computation load of single unmanned aerial vehicle, and guarantees the real-time performance of broadcast unmanned aerial vehicles during task performing.

A system and method for controlling vehicular traffic flow is disclosed, which creates a communication system between vehicles that allows the vehicles to share their respective velocities and acceleration or deceleration rates. Thus, each vehicle within the system can respond immediately to any acceleration or deceleration rate changes of the surrounding vehicles (e.g., the vehicle directly in front, directly in back, and in the adjacent lane). Essentially, the system functions similar to a wireless vehicular train, with a queue of cars linked together by a stiff, wireless communications “chain”. Notably, the term “vehicle” is not limited only to land-based vehicles (e.g., motor vehicles), and the system can include airborne vehicles (e.g., multiple aircraft flying in close formation, military aircraft flying in drone formation, etc.). For example, a system for controlling vehicular traffic flow is disclosed, which includes in each vehicle of a plurality of vehicles, a wireless or infrared (IR) modem for inter-vehicular communications, a range finder for determining the distance and closing rate between vehicles, a processing unit for retrieving vehicular operational data (e.g., velocity, angular velocity, acceleration rate, deceleration rate, braking pressure, weight, pointing vector, etc.) and executing flow control system software instructions, and a vehicular flow control communications protocol that enables the communication of various flow control parameters between vehicles via the wireless or IR modem. Thus, each vehicle in the system “knows” what the surrounding vehicles are doing and can respond immediately to changes in the traffic flow. As such, the system minimizes the distribution of vehicles' velocities in the queue, and increases traffic throughput and safety as a result.

An aircraft formation positioning system lead aircraft transmits a continuous RF signal and a periodic data burst with lead aircraft position. A follower aircraft receives the continuous RF signal and the periodic data burst. A follower aircraft resolver determines bearing, distance and elevation relative to the lead aircraft from the continuous RF signal. The follower aircraft transmits an intermittent RF signal and a periodic data burst with its relative position determined from the continuous RF signal. The lead aircraft receives the intermittent RF signal and the periodic data burst from the follower aircraft. A lead aircraft resolver performs an independent measurement of the lead aircraft position relative to the follower aircraft from the intermittent RF signal. A lead aircraft Kalman filter connected to the lead aircraft resolver and receiver correlates the independent measurement of the lead aircraft position relative to the follower aircraft with the received periodic data burst.

An aircraft formation/refueling guidance system guides a follower aircraft relative to a leader aircraft. A datalink provides a position hold and a bias command from the leader aircraft to the follower aircraft. An optical tracker onboard the follower aircraft takes an image of the leader aircraft when receiving the hold command, tracks the leader aircraft using the image, and provides optical tracker movement outputs. A resolver resolves the optical tracker movement outputs to provide resolver control signals. A vernier control receives the bias command to change a position of the follower aircraft by biasing the resolver control signals with a bias signal. A sum circuit connected to the resolver and to the vernier control receives the resolver control signals and the bias signal to provide a sum circuit output signal. An autopilot and autothrottle receives the sum circuit output signal and the position hold command to control the follower aircraft.

The invention discloses a multi-unmanned-aerial-vehicle cluster to-the-ground observation system and a formation control method thereof. The system comprises a plurality of unmanned aerial vehicles. A plurality of ground stations corresponding to the unmanned aerial vehicles in a one-to-one mode are arranged on the ground, and the ground stations carry out information interaction through a task management machine. The unmanned aerial vehicles send waypoint information to the corresponding ground stations. The ground stations are used for receiving the waypoint information sent by the unmanned aerial vehicles and sending the waypoint information to the task management machine. The task management machine is used for receiving the waypoint information sent by the ground stations and controlling the formation of the unmanned aerial vehicles according to the waypoint information. By adopting the system and the method, the capability of multi-mode, multi-angle and high-reliability data acquisition in a variety of environments can be realized through precision formation. Operation is simple and efficient. The system is stable and reliable.

The invention discloses an unmanned aerial vehicle formation method based on a small bird cluster flight mechanism. The unmanned aerial vehicle formation method includes the implementation steps that 1, an unmanned aerial vehicle communication network based on a bird flock hierarchical structure is designed; 2, a formation navigator based on bird flock foraging behaviors is designed; 3, a formation controller based on bird flock neighbor interaction behaviors is designed; 4, a flight mode switching device based on bird flock behaviors is designed. Through the method, formation and shaping of multiple unmanned aerial vehicles can be realized stably, and the method adapts to different task environments, and provides the feasible technical means for large-scale cluster formation of small unmanned aerial vehicles.

In a method for the flight control of a plurality of aircraft flying in formation with respect to one another, correction signals are generated for an autopilot system or a command display in order to allow one or more following aircraft within the formation to follow a lead aircraft in the formation in a predeterminable relative position. A nominal trajectory of the following aircraft, parallel to the trajectory (1) of the lead aircraft, is calculated at each instantaneous position P′_act of the following aircraft, which trajectory runs through the instantaneous actual position P′_act and a reference point P′_RP. (The reference point P′_RP is the projection of a point P_RP, which is separated by the longitudinal nominal distance x_nom between the lead aircraft and the following aircraft, on the trajectory of the lead aircraft, taking into account the lateral and vertical actual distances y_act and z_act between the trajectory of the lead aircraft and that of the following aircraft. The trajectory of the following aircraft is calculated taking into account the lateral actual distance y_act from the trajectory of the lead aircraft by determining support points P′ on the trajectory of the following aircraft which have the same time coordinates as the corresponding support points on the trajectory of the lead aircraft. The correction signals are determined by i) measuring the longitudinal, lateral and vertical actual distances x_act, v_act and z_act between the trajectory of the lead aircraft and that of the following aircraft at the instantaneous position P′_act of the following aircraft, ii) calculating the longitudinal deviation Δx, the vertical deviation Δz and the lateral deviation Δy of the instantaneous actual position P′_act and of the nominal position P′_nom of the following aircraft from the respective nominal values x_nom, z_nom, y_nom and the measured actual values x_act, z_act, y_act, iii) calculating the nominal speed and the nominal acceleration of the following aircraft at the point P′_RP, and iv) calculating the nominal curvature, the nominal climbing rate and the nominal curvature angle Ψ of the trajectory of the following aircraft at the instantaneous position P′_act of the following aircraft.

The invention provides an ethernet-exchange-bus-based unmanned plane flight control system and method. The system comprises a flight control computer (ARM), a flight indication lamp control module (LED+), an ultrasonic sensor, a light stream sensor, a power management unit (PMU), a storage battery, an inertia management unit (IMU), a satellite navigation unit (GPS/BD+), a motor, and a steering engine. An Ethernet exchange chip (LAN swtich) is embedded into the flight control computer (ARM) and is connected with the flight control computer (ARM) by an LAN and is connected with a flight control peripheral module by an LAN. The system and method have the following beneficial effects: a communication link between an unmanned plane and the ground is simplified; a high-definition digital image can be returned to the ground in real time or be connected to the interne or be passed back to a command center; the visual navigation, obstacle avoidance, and image target identification tracking are supported; the communication demand of the unmanned plane formation flight is satisfied; the traditional IOSD equipment as well as the investment are saved; and the new function of the modularized smooth extension flight control is supported.

The invention discloses an unmanned aerial vehicle (UAV)-unmanned ground vehicle (UGV) combined formation cooperative control method, comprising the following steps: step 1, establishing nonlinear dynamical models of unmanned vehicles in UAV-UGV combined formation; step 2, processing the nonlinear dynamical models of a UAV and a UGV via equivalent transformation, and taking acceleration as a common control target quantity, obtaining a unified control model taking acceleration as a control input in the combined formation; step 3, establishing a ground-air combined formation structure based on a virtual pilot to obtain a stable control signal for the UAV-UGV combined formation and obtain an error model of the combined formation, wherein the control signal is acceleration obtained in step 2 as a common control target quantity; and step 4, designing a UAV-UGV combined formation controller by adopting a RBF (Radial Basis Function) network algorithm according to the control model, the error model and the acceleration serving as a control signal and a control target quantity at the same time, so that the combined formation is stable and reliable.

The invention relates to a design method for the formation configuration of distributed satellites with synthetic aperture radars (SAR). The method comprises the following five operation steps: step 1: designing the formation configuration of the distributed satellites and conforming fly-by path equations; step 2: confirming an optimal base line length range of the distributed satellites in start time; step 3: confirming an optimal base line sequence of the distributed satellites in start time; step 4: confirming track parameters of the formed satellites forming a concentric circle configuration; and step 5: calculating effective base lines and vertical path base lines in a track period. The invention provides the concentric circle formation configuration, uses the optimal base line combined constraint conditions of multi-base line interference SARs as design input parameters and designs a control law of radar antenna visual angles to realize that a distributed satellite SAR system can satisfy the design requirements of the optimal base line combined constraint conditions in any time in a track operation period and a basis is provided for the distributed satellite SAR system to obtain high-precision DEM products by a multi-base line interference SAR treatment method.

The invention discloses an air-based large-scene photographing system and method. The system is composed of a multi-rotor unmanned machine set subsystem, a multi-rotor unmanned machine flight ground control subsystem and a ground image data processing and display terminal subsystem. According to the air-based large-scene photographing system and method, multiple multi-rotor unmanned machines are controlled to conduct the formation flight by additionally hanging cameras below the multi-rotor unmanned machines, the reasonable position layout of multiple aircrafts is achieved in space near the ground, and images photographed by the unmanned machines are sent back to the ground in real time; the ground image data processing and display terminal subsystem receives the image data, projection converting and splicing processing are conducted on the images photographed by the multi-rotor unmanned machines through an image analyzing and machine vision technology, and finally two-dimensional splicing on remote large-scene scenes is formed. The system is suitable for rebuilding of large scenes and observing and measuring of points of impact when various military exercises and target practicing and shooting are conducted.

The invention relates to a spacecraft fault tolerance attitude cooperation tracking control method based on a normalized neural network, and belongs to the technical field of spacecraft formation flight. According to the method, an attitude motion model of a single spacecraft is built, errors are defined, a control law is designed for the model, a sliding mode function is designed, the derivative of the sliding mode function is solved, an error model is obtained, a control law based on an input normalized neural network is designed, and the states of the spacecrafts are cooperative and consistent; each spacecraft calculates the required control torque according to attitude information of itself and the adjacent spacecraft, the calculated control torque is acted on the corresponding spacecraft via an execution mechanism of each spacecraft, the angular velocity is solved via an obtained attitude dynamic equation, a unit quaternion attitude tracks an expected attitude via the attitude dynamic equation, and consistent attitude of the spacecraft formation is finally realized. According to the method, estimation errors of non-linear function approximation are reduced, the calculating time is reduced, and the convergence rate and the control precision of the system are increased.

The invention discloses a decoupling control method for relative orbits and attitudes of formation satellites, relates to the technical field of the control of the orbits and attitudes of a spacecraft formation, and solves the problems of large satellite calculation amount and low orbit solving efficiency caused by high control dimension of the formation satellites due to serious coupling of the relative orbits and the attitudes of the formation satellites. The method gives two decoupling conditions at first, so that the control of the relative orbits and the attitudes can be designed independently; a thrust vector mobility decoupling constraint condition is introduced to the initialization control of the relative orbits according to satellite attitude mobility constraints indirectly; and during the optimal thrust vector attitude tracking, the possible orientation in space, which meets solar avoidance constraints, of a star sensor optical axis (1) is sought by using a geometric method, and the optimal attitude quaternion and attitude angular velocity are calculated finally by using a double-vector attitude determination algorithm. The method provides important reference value for the control of the orbits and the attitudes of the spacecraft formation.

A collision avoidance system and method is based on receiving and processing Mode-S transponder messages without interrogating the transponders of the respective aircraft flying in formation. A collision avoidance computer and Mode-S transponder are used to provide distributed intra-formation control among multiple cells of aircraft flying in formation or close-in. The Mode-S transponder provides ADS-B Global Positioning System (GPS) squitter data to the computer. A mission computer is coupled to the collision avoidance computer. The mission computer may provide steering commands transmitted to other formation member aircraft. The method and system allow a safe separation between 2 to 250 aircraft flying in formation at selectable ranges.