RU2777576C1 - System for refuelling an unmanned aerial vehicle in flight - Google Patents

Abstract

FIELD: aviation.

SUBSTANCE: system for refuelling an unmanned aerial vehicle (UAV) in flight comprises the equipment of the UAV refueller and the equipment of the refuelled UAV. The equipment of the UAV refueller comprises a fuelling hose with a cone installed at one end, a refuelling set, a control unit, a cone position sensor, and a docking sensor, installed on the cone of the fuelling hose. The equipment of the refuelled UAV comprises a fuelling rod, a cone position detection unit, a misalignment parameter computing unit, and a fuel level sensor.

EFFECT: increased safety and reliability of docking and undocking for automatic refuelling in flight.

2 cl, 4 dwg

Description

The invention relates to aviation, and more specifically to equipment that provides in-flight refueling of aircraft (AC) and can be used in a system of unmanned aerial vehicles-refuelers and refueling unmanned aerial vehicles (UAVs) in order to increase the efficiency of the use of the latter, namely , increasing the time spent in the air, the radius of combat use, the mass of the payload during takeoff.

Known "In-flight aircraft refueling system" (see RF patent No. 2104229, C1, IPC B64D 39/00). The refueling system includes a refueling hose with a cone mounted on the refueling aircraft, a hose releasing device, a refueling bar mounted on the refueling aircraft, cone and refueling bar position sensors, a means for determining the relative position of the cone and refueling bar containing a calculator. The system uses satellite navigation system (SNS) receivers designed for high-precision measurement of the relative coordinates and velocities between the refueling aircraft, the refueling aircraft and the cone, which are displayed on the indicator screen, and on the basis of which the pilot of the refueling aircraft controls the aircraft until the refueling bar hits the cone and docking production. However, this system is not designed to solve the problem of UAV refueling. The disadvantage of this system is the dependence on the SNS, which leads to the complication of the onboard equipment of the aircraft.

The closest analogue of the invention is the "Method and device for in-flight refueling of an unmanned aircraft" (see US patent No. 5131438, class B64D 39/00), which can be taken as a prototype.

The device comprises a retractable refueling hose on the unmanned aircraft, equipped with a refueling cone, a hose control device controlled from a refueling aircraft equipped with a refueling bar. In addition, the device is equipped with a transmitter mounted on a tanker aircraft and a receiving means mounted on an unmanned aircraft, receiving signals from the transmitter and a hose control device. In this case, the receiving and transmitting means are made in the form of inductive self-excitation coils mounted on the cone and the filling rod.

The disadvantages of such a system are large psychophysical loads on the tanker pilot due to the lack of accurate coordinates about the relative position of the cone and rod, the possibility of using only with a small distance between them, which reduces the reliability and safety of refueling, as well as the impossibility of refueling in adverse weather conditions. especially at night time.

The technical result, to which the present invention is directed, is the automatic refueling of the UAV in flight, as well as an increase in safety and reliability at the docking stage.

The technical result is achieved by the fact that the proposed system for refueling UAVs with fuel in flight ensures organized interaction of aircraft, bringing UAVs to the refueling zone and efficient docking of the UAV tanker cone with the fueling bar of the refueling UAV at any time of the year and day, regardless of the satellite navigation system.

The essence of the invention lies in the fact that the in-flight UAV refueling system contains equipment installed on the UAV tanker as part of a refueling hose with a cone installed at one end, a refueling unit, the outlet of which is connected to the other end of the refueling hose, and equipment installed on the refueling UAV as part of the refueling bar, a control unit is additionally introduced, the output of which is connected to the input of the refueling unit, and a cone position sensor and a docking sensor installed on the cone of the refueling hose, the output of which is connected to the second input of the control unit, and the equipment installed on the refueling UAV, a unit for determining the position of the cone and a unit for calculating the mismatch parameters are introduced, as well as a fuel level sensor installed in the tank, the output of which is connected to the second input of the unit for calculating the mismatch parameters, and at the same time the control unit and the unit for calculating the mismatch parameters are connected by a communication line, as well as a block for determining the position of the cone is installed on the filling rod at a predetermined distance from the docking unit of the filling rod and is connected to the cone position sensor by an optical communication line, and in addition, the block for calculating the misalignment parameters is connected to the automatic control system (ACS) and the inertial navigation system (INS) of the refueling UAV, and the control unit is connected to the INS of the UAV tanker.

In FIG. 1 shows a block diagram of an in-flight UAV refueling system, which includes equipment installed on a tanker UAV and equipment installed on a UAV being refueled; in fig. 2 is an exemplary RFID tag (RFIM) code structure; in fig. 3 - scheme of interaction of the UAV tanker with the group of UAVs in the refueling zone; in fig. 4 - the position of the cone in the coordinate system of the block for determining the position of the cone.

The equipment of the UAV-refueler 1 includes (see Fig. 1): a filling hose 5, with a cone 6 installed at one end, a filling unit 4, the outlet of which is connected to the other end of the filling hose, a control unit 3 and a docking sensor installed on the cone of the filling hose 7 and cone position sensor (CDP) 8.

The equipment of the refueling UAV 2 includes (see Fig. 1): a filling rod 10, a block for determining the position of the cone 9, a block for calculating the mismatch parameters 11, and a fuel level sensor 12.

Refueling unit 4 can be made, for example, in the form of an automatic control unit for the processes of releasing and retracting a filling hose with a cone and supplying fuel, and must include electrical equipment that provides power to the WPC and systems that implement these processes.

The cone of the filling hose 6 can be of a known design, in addition, the docking sensor 7 and the WPC 8 are placed on it.

The docking sensor 7, as part of the filling cone 6, is designed to issue a signal to the control unit 3 about the docking (undocking) of the filling rod 10 and the cone 6.

WPC 8, when measuring the parameters of the relative position of the cone 6 and the filling rod 10, can be made, for example, in the form of two sources of optical radiation (markers), which are located on the rim of the cone 6 diametrically opposite to each other horizontally to exclude the possibility of shading one of markers when the filling rod 10 approaches the cone 6, and “illuminate” it with their radiation for recognition by the block for determining the position of the cone 9.

The block for determining the position of the cone 9 is designed to output to the block for calculating the mismatch parameters 11 the coordinates of the cone 6, the distance to the cone and the speed of approach to it, and can be made, for example, in the form of a lens with a digital matrix mounted on the filling rod 10 so that the direction its aperture coincided with the direction of the filling rod axis.

The fuel level sensor 12, located in the tank of the refueling UAV, is designed to issue a signal to the mismatch parameters calculation unit 11 that the required fuel level value has been reached.

The control unit 3 as part of the UAV-refueling equipment 1 and the mismatch parameter calculation unit 11 as part of the equipment of the UAV 2 being refueled can be implemented, for example, as on-board digital computers (OBCM) associated with transceiver devices that generate signals based on the initial and incoming data controls supplied to the actuators. At the same time, the control unit 3 of the UAV tanker and the unit for calculating the mismatch parameters 11 of the UAV being refueled are connected by a communication line.

Thus, the control unit 3 performs the main functions of interacting with refueling UAVs, managing the processes of releasing and retracting the filling hose 5 with a cone 6 and supplying fuel. The mismatch parameters calculation unit 11, in turn, solves the problem of ensuring interaction with the UAV tanker, generates the mismatch parameters and outputs them to the ACS of the refueling UAV, thereby ensuring that the refueling UAV enters the refueling zone, maneuvering the refueled UAV to approach the refueling cone and docking with him.

The operation of the UAV refueling system in flight can be performed according to a newly developed algorithm consisting of several stages:

stage 1 - exit of the refueling UAV into the refueling zone and entry of the refueling UAV into the rear hemisphere (ZPS);

stage 2 - rendezvous with the UAV tanker;

stage 3 - docking of the filling rod of the refueling UAV with the cone of the UAV tanker;

Stage 4 - refueling and undocking.

The first stage is the exit of the refueling UAV to the refueling zone and the entry of the UAV-refueler into the ZPS. At this stage, a special zone is assigned for refueling, the boundaries of which are entered into the memory of the onboard computer of the UAV (for example, at the stage of pre-flight preparation). In the established zone, a UAV tanker patrols. Interaction with him each UAV group is carried out, for example, based on the use of well-known technology of radio frequency identification marks (RFIM).

RFFM in the proposed system is a code transmitted over radio frequency channels, containing, for example, the following information: the password of the “friend or foe” identification system, the UAV tail number, the remaining fuel (kg), the remaining ammunition of aviation weapons (ASP) (kg) , UAV coordinates that determine its current location. The current location of the UAV can be determined in various ways, for example, using an inertial navigation system (INS). An exemplary RFFM code structure is shown in FIG. 2.

The UAV, when entering the refueling zone, by means of an omnidirectional antenna, periodically emits radio pulses into space containing a request to receive information from the refueling UAV located in the refueling zone about its coordinates. Upon receipt of a request, the UAV-refueler, by means of an omnidirectional antenna, radiates radio pulses into space containing information about its coordinates and a request to receive data from the UAVs located in the refueling zone. When they are received, the UAVs transmit the information recorded on them by means of RFFM, which is sent for processing to the control unit on board the UAV tanker (Fig. 3).

In the process of information processing, the order of UAV service and the resolution of conflict situations, if any, are determined. A conflict can arise when a service request is received from several UAVs at the same time. To resolve the conflict, the principle of priority is used according to the following parameters: the remaining fuel (OT), the remaining ammunition of the ASP (OASP), the removal of the UAV from the UAV tanker. Priority is given to the UAV with the lowest of the compared OT. If this parameter is equal, the UAV with the highest UASF takes priority. If this parameter is equal, the priority is given to the UAV with the smallest distance from the tanker UAV. As a result, a UAV refueling sequence list is formed, according to which the UAV tanker sends commands via a radio frequency channel to approach, rendezvous and dock for refueling a UAV with a certain number.

The UAV, which received a command from the UAV tanker to approach to perform refueling, using the coordinates of the UAV tanker, changes its movement parameters in such a way as to approach the UAV tanker along the shortest path and end up in its APS.

The second stage is the rendezvous with the UAV tanker. This stage begins from the moment the tanker UAV enters the ZPS. Previously, the UAV tanker control unit generates a control signal to release the filling hose with a cone and supply power to the WPC.

When a cone is detected in the block for determining the position of the cone, the estimated values of the coordinates of the cone, the range and speed of approach to it are formed, which are fed into the block for calculating the mismatch parameters. The estimate of the cone coordinates can be realized, for example, on the basis of the newly obtained quasi-optimal filtration equations

- текущие оценки координат центра конуса, радиуса и случайной начальной фазы изменения углового положения маркера относительно центра изображения;

- эквивалентные постоянные времени; R - радиус маркера, N - спектральная плотность шума; П₁, П₂, П₃, П₄ - показатели степени, имеющие видwhere

- current estimates of the coordinates of the center of the cone, the radius and the random initial phase of the change in the angular position of the marker relative to the center of the image;

- equivalent time constants; R - marker radius, N - noise spectral density; P ₁ , P ₂ , P ₃ , P ₄ - exponents having the form

относительно координат центра матрицы объектива (X₀; Y₀) блок расчета параметров рассогласования выдает в САУ следующие параметры (фиг. 4)Based on certain parameters of the position of the duodenum

relative to the coordinates of the center of the lens matrix (X ₀ ; Y ₀ ), the block for calculating the misalignment parameters outputs the following parameters to the ACS (Fig. 4)

Mismatch parameters Δ _Г and Δ _В determine the angular deviations of the line of sight of the cone relative to the longitudinal axis of the filling rod in the horizontal and vertical planes, and the parameter δ is the deviation of the center of the lens aperture from the center of the cone. The ACS, using the specified parameters, generates control actions on the steering mechanisms to deflect the corresponding rudders (direction, height, ailerons, flaperons) in such a way as to reduce the values of the mismatch parameters to zero. In this case, maneuvering should be carried out without deflecting the UAV in yaw and pitch angles.

The distance to a cone with known dimensions is uniquely determined by the size of its image on the lens matrix, and the change in range is used to calculate the approach velocity as a derivative of the distance.

The third stage is the docking of the refueling bar of the refueling UAV with the cone of the refueling unit of the refueling UAV. This stage is the most important in terms of safety and reliability of docking and begins when approaching the cone at a distance of several meters. At this stage, the deviation of the center of the lens aperture from the center of the cone should not exceed half the radius of the cone. To do this, the current mismatch parameter δ is compared with the required δ _T , which is determined by the expression

If δ>δ _T , then from the unit for calculating the mismatch parameters in the ACS of the UAV, a signal is received to move away from the cone, after which the mismatch is worked out and the approach continues until the moment of docking.

The fourth stage is refueling and undocking. After the filling rod has docked with the cone, a signal is sent from the docking sensor to the control unit. The control unit, having received a signal from the docking sensor, issues an enabling signal to the automatic control unit for the fuel supply process of the refueling unit, and the process of transferring fuel from the tanker UAV to the refueling UAV begins. At the moment when the fuel level reaches a certain value, the signal from the fuel level sensor enters the unit for calculating the mismatch parameters of the refueling UAV and is transmitted to the control unit of the refueling UAV via the communication line, while the control unit issues a prohibiting signal to the automatic control unit for the fuel supply process of the unit refueling, at the same time, the transfer of fuel is stopped and an enabling signal for undocking is returned from the UAV tanker.

Thus, the proposed in-flight refueling system for UAVs will make it possible to refuel UAVs in flight at any time of the year and day in automatic mode, increase reliability and safety at the docking stage, and, if used for manned aircraft, significantly reduce psychophysical stress on the aircraft crew . This eliminates the shortcomings of the prototype.

The proposed technical solution is new, since from publicly available information there is no known in-flight UAV refueling system that operates under the conditions of the presented algorithm for the interaction of the UAV-refueling UAV and the UAV being refueled and allows estimating the coordinates of the cone, the distance to the cone and the speed of approach with it according to the one formed in the block determining the position of the cone to the image, characterized in that the equipment installed on the refueling UAV additionally includes a control unit and a cone position sensor and a docking sensor installed on the cone of the filling hose, and a position determination unit is introduced into the equipment installed on the refueling UAV cone and a block for calculating mismatch parameters, as well as a fuel level sensor installed in the tank. In addition, the control unit of the refueling UAV and the unit for calculating the mismatch parameters of the refueling UAV are connected by a communication line, while the unit for calculating the mismatch parameters is connected to the automatic control system and the inertial navigation system of the refueling UAV, and the control unit is connected to the inertial navigation system of the refueling UAV.

The proposed technical solution is practically applicable, since for its implementation regular means that are part of the aircraft avionics equipment can be used.

Claims (2)

1. A system for refueling an unmanned aerial vehicle with fuel in flight, containing equipment installed on an unmanned aerial vehicle refueling vehicle as part of a refueling hose with a cone installed at one end, a refueling unit, the outlet of which is connected to the other end of the refueling hose, and equipment installed on the refueling an unmanned aerial vehicle as part of a filling rod, characterized in that the equipment installed on the unmanned aerial vehicle refueling unit additionally includes a control unit, the output of which is connected to the input of the refueling unit, and a cone position sensor and a docking sensor installed on the cone of the refueling hose, the output of which is connected to the second input of the control unit, and the equipment installed on the refueling unmanned aerial vehicle includes a unit for determining the position of the cone and a unit for calculating the misalignment parameters, connected in series, as well as installed in the tank d a fuel level sensor, the output of which is connected to the second input of the mismatch parameters calculation unit, and the control unit and the mismatch parameters calculation unit are connected by a communication line. 2. The system for refueling an unmanned aerial vehicle with fuel in flight according to claim 1, characterized in that the block for determining the position of the cone is installed on the filling rod at a predetermined distance from the docking node of the filling rod and is connected to the cone position sensor by an optical communication line, while the parameter calculation unit mismatch is connected to the automatic control system and the inertial navigation system of the unmanned aerial vehicle being refueled, and the control unit is connected to the inertial navigation system of the unmanned aerial vehicle tanker.

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