A method for handling double aircraft avoidance

Abstract

The present application relates to the field of UAV avoidance technology, and in particular to a method for processing dual-aircraft avoidance. The method comprises: obtaining the horizontal speed V of the first UAV 1 and the horizontal speed V of the second UAV 2 ; If V 1 >V 2 , then V 3 ×t 1 +(V 1 ×V 1 ) / (2×a 1 ) is determined as the flight technical error FTE; if V 1 <V 2 , then V 3 ×t 2 +(V 2 ×V 2 ) / (2×a 2 ) is determined as FTE; based on FTE, the radius r of the first UAV 1 and the radius r of the second drone 2 Get the total error distance PCA; Get the maximum turning angle θ of the first drone 1 and the maximum turning angle θ of the second UAV 2 ; According to PCA, θ 1 ,θ 2 , R 1 and R 2 Get the horizontal avoidance distance d between the first UAV and the second UAV avoid The present invention can evaluate the safety interval between two UAVs and reduce the potential collision risk between the two UAVs.

Description

Technical Field

[0001] The present invention relates to the technical field of UAV avoidance, and particularly to a processing method for dual-UAV avoidance. Background Art

[0002] In the field of safety intervals, the intervals between traditional civil airliners and between civil airliners and UAVs have been studied in a considerable amount of literature, while the interval between UAVs has relatively less literature. In the prior art, the research on the collision risk and safety interval between UAVs is mostly based on the Event model or the Reich model, limited to the risk assessment of simulation or collision models, and cannot evaluate the safety interval (i.e., the avoidance distance) between UAVs according to the actual scenarios (including the speed, navigation position error, avoidance maneuverability, and wind speed when UAVs meet), and there will still be a large potential for UAV collisions. Summary of the Invention

[0003] The object of the present invention is to provide a processing method for dual-UAV avoidance to evaluate the safety interval between two UAVs according to the actual scenario and reduce the potential for collision between the two UAVs.

[0004] According to the present invention, there is provided a processing method for dual-UAV avoidance, the method comprising the following steps:

[0005] S100, obtaining the horizontal speed V1 of the first UAV and the horizontal speed V2 of the second UAV.

[0006] S200, if V1 > V2, then determining V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 < V2, then determining V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE; V3 is the average wind speed in the horizontal direction at the positions of the first UAV and the second UAV, t1 and t2 are the times for the first UAV and the second UAV to correct the flight path when encountering a wind of magnitude V3 in the horizontal direction, and a1 and a2 are the accelerations of the first UAV and the second UAV in the horizontal direction respectively.

[0007] S300, obtaining the total error distance PCA according to FTE, the radius r1 of the first UAV, and the radius r2 of the second UAV; PCA=(FTE 2 +NSE 2 ) 0.5 +r1+r2, where NSE is a preset navigation performance error.

[0008] S400, obtaining the maximum turning angle θ1 of the first UAV and the maximum turning angle θ2 of the second UAV.

[0009] S500. Obtain the turning radius R1 of the first drone based on θ1 and V1.

[0010] S600. Obtain the turning radius R2 of the second drone based on θ2 and V2.

[0011] S700. Obtain the horizontal avoidance distance d between the first drone and the second drone based on PCA, θ1, θ2, R1, and R2 avoid ; d avoid =(((V1×sin(θ1)+V2×sin(θ2))×t0) 2 +(PCA+R1×θ1+R2×θ2) 2 ) 0.5 , where t0 is the preset avoidance time.

[0012] Furthermore, S200 further includes: If V1 = V2 and a1 > a2, then determine V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 = V2 and a1 < a2, then determine V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE.

[0013] Furthermore, S200 further includes: If V1 = V2, a1 = a2, and t1 ≥ t2, then determine V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 = V2, a1 = a2, and t1 < t2, then determine V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE.

[0014] Furthermore, V3 satisfies the following relationship: V3=(V 3,1 +V 3,2 ) / 2, where V 3,1 and V 3,2 are the horizontal wind speeds at the positions of the first drone and the second drone respectively.

[0015] Furthermore, R1 satisfies the following relationship: R1=(V1×V1) / (g×((LF1×LF1 - 1) 0.5 ))’, where g is the acceleration due to gravity, ( )’ is the derivative, LF1 is the load factor of the first drone, and LF1 = 1 / (cos(θ1))’.

[0016] Furthermore, R2 satisfies the following relationship: R2=(V2×V2) / (g×((LF2×LF2 - 1) 0.5 ))’, where g is the acceleration due to gravity, ( )’ is the derivative, LF2 is the load factor of the second drone, and LF2 = 1 / (cos(θ2))’.

[0017] Further, the NSE is 9.14 meters.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] For the scenario of two-aircraft avoidance, the present invention combines the horizontal speed, acceleration, horizontal wind speed and the time to correct the route when encountering horizontal wind of the first UAV and the second UAV to obtain the flight technical error, and combines the navigation performance error to obtain the total error distance of the first UAV and the second UAV; on this basis, the present invention further combines the maximum turning angle of the first UAV and the second UAV to obtain the horizontal avoidance distance of the first UAV and the second UAV, that is, the horizontal safety interval of the first UAV and the second UAV. The horizontal safety interval obtained by the present invention is the safety interval of the first UAV and the second UAV in the horizontal direction. Compared with the horizontal safety interval obtained according to the simulation or collision model in the prior art, the horizontal safety interval obtained by the present invention is determined according to the actual flight scene of the first UAV and the second UAV, and has higher accuracy. The horizontal safety interval obtained by the present invention is used as a reference for the first UAV and the second UAV to avoid collision in the horizontal direction, which can reduce the hidden danger of collision between the first UAV and the second UAV in the horizontal direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 A flowchart of a method for processing dual aircraft avoidance provided by an embodiment of the present invention;

[0022] Figure 2 A schematic diagram of horizontal avoidance when two aircraft are flying head-on provided in an embodiment of the present invention;

[0023] Figure 3 A schematic diagram of a case where the horizontal speeds of two machines are at a relative angle provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0025] According to this embodiment, Figure 1 As shown in the figure, a method for the avoidance of two drones is provided. The method includes the following steps:

[0026] S100, obtaining the horizontal speed V1 of the first drone and the horizontal speed V2 of the second drone.

[0027] In this embodiment, the speed of the drone is a vector. The speed of the first drone is decomposed into two components, namely the horizontal speed and the vertical speed. The obtained horizontal speed is V1; the speed of the second drone is decomposed into two components, namely the horizontal speed and the vertical speed. The obtained horizontal speed is V2.

[0028] S200, if V1 > V2, then determining V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 < V2, then determining V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE; V3 is the average wind speed in the horizontal direction at the positions of the first drone and the second drone, t1 and t2 are the times for correcting the flight path when the first drone and the second drone encounter a wind with a magnitude of V3 in the horizontal direction respectively, and a1 and a2 are the accelerations of the first drone and the second drone in the horizontal direction respectively.

[0029] In this embodiment, V3 satisfies the following relationship: V3=(V 3,1 +V 3,2 ) / 2, where V 3,1 and V 3,2 are the wind speeds in the horizontal direction at the positions of the first drone and the second drone respectively. Those skilled in the art know that any method for obtaining the wind speed at the position of the drone in the prior art falls within the protection scope of the present invention.

[0030] In this embodiment, t1 and t2 are obtained by conducting experiments on the first drone and the second drone in advance respectively.

[0031] As a specific embodiment, if V1 = V2 and a1 > a2, then determining V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 = V2 and a1 < a2, then determining V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE.

[0032] As a specific embodiment, if V1 = V2, a1 = a2 and t1 ≥ t2, then determining V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 = V2, a1 = a2 and t1 < t2, then determining V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE.

[0033] S300, obtaining the total error distance PCA according to FTE, the radius r1 of the first UAV and the radius r2 of the second UAV; PCA=(FTE 2 +NSE 2 ) 0.5 +r1+r2, NSE is the preset navigation performance error.

[0034] As a specific implementation, the Beidou navigation performance error is determined as a preset navigation performance error, and the NSE is 9.14 meters.

[0035] S400: Obtain a maximum turning angle θ1 of the first UAV and a maximum turning angle θ2 of the second UAV.

[0036] In this embodiment, the maximum turning angle of the drone is directly given by the drone manufacturer.

[0037] In this embodiment, the unit of the maximum turning angle is radian.

[0038] S500: Obtain a turning radius R1 of the first UAV according to θ1 and V1.

[0039] As a specific implementation, R1 satisfies the following relationship: R1=(V1×V1) / (g×((LF1×LF1-1) 0.5 )'), where g is the acceleration due to gravity, ( )' is the derivative, LF1 is the load factor of the first UAV, LF1=1 / (cos(θ1))'.

[0040] S600: Obtain a turning radius R2 of the second UAV according to θ2 and V2.

[0041] As a specific implementation, R2 satisfies the following relationship: R2=(V2×V2) / (g×((LF2×LF2-1) 0.5 )'), where g is the acceleration due to gravity, ( )' is the derivative, LF2 is the load factor of the second UAV, LF2=1 / (cos(θ2))'.

[0042] S700: Obtain the horizontal avoidance distance d between the first UAV and the second UAV according to PCA, θ1, θ2, R1 and R2 avoid ;d avoid =(((V1×sin(θ1)+V2×sin(θ2))×t0) 2 +(PCA+R1×θ1+R2×θ2) 2 ) 0.5 , t0 is the preset avoidance time.

[0043] In this embodiment, the path of each UAV during the avoidance process is regarded as an arc, such as Figure 2As shown, it is known that the horizontal speeds of the first UAV and the second UAV are V1 and V1 respectively, the maximum turning angles of the first UAV and the second UAV are θ1 and θ2 respectively, and the turning radii of the first UAV and the second UAV are R1 and R2 respectively; after t time, the positions of the first UAV and the second UAV are (x1(t), y1(t)) and (x2(t), y2(t)) respectively, and the distance d(t) between the first UAV and the second UAV satisfies the following relationship: d(t)=((x2(t)-x1(t)) 2 +(y2(t)-y1(t)) 2 ) 0.5 .

[0044] The turning rates of the first UAV and the second UAV are ω1 and ω2 respectively, and ω1 and ω2 respectively satisfy the following relationship: ω1=V1 / R1, ω2=V2 / R2.

[0045] The position of the UAV during the turning process can be modeled according to the kinematic process. The positions x1(t) and y1(t) of the first UAV respectively satisfy the following relationship: x1(t)=R1×sin(ω1×t), y1(t)=R1×cos(ω1×t); the positions x2(t) and y2(t) of the second UAV respectively satisfy the following relationship: x2(t)=R2×sin(ω2×t), y2(t)=R2×cos(ω2×t).

[0046] At the end of the avoidance process (i.e., the turning angles of the first UAV and the second UAV reach θ1 and θ2 respectively), the distance d between the first UAV and the second UAV is final Satisfies the following relationship: d final =((R2×sinθ2-R1×sinθ1) 2 +(R2×cosθ2-R1×cosθ1) 2 ) 0.5 .

[0047] At t=0, the distance d between the initial positions of the first UAV and the second UAV is avoid Satisfies the following relationship: d avoid =((x2(0)-x1(0)) 2 +(y2(0)-y1(0)) 2 ) 0.5 .

[0048] Combining the above relationship, we can get d avoid =(((V1×sin(θ1)+V2×sin(θ2))×t0) 2 +(PCA+R1×θ1+R2×θ2) 2 ) 0.5 , where t0 is the preset avoidance time.

[0049] In this embodiment, when the first drone and the second drone face each other, avoid is determined as the horizontal avoidance distance between the first UAV and the second UAV. If there is a relative angle α (α is greater than 0°) between the first UAV and the second UAV, such as Figure 3 As shown, the horizontal avoidance distance obtained is less than d avoid Therefore, this embodiment directly converts d avoid The horizontal avoidance distance determined for the first UAV and the second UAV can meet the safety interval requirement for the first UAV and the second UAV flying head-on or having a relative angle with each other at horizontal speeds.

[0050] As a specific implementation, QGroundControl is used to perform a UAV avoidance distance calculation experiment. It is an open source UAV ground control station software, also known as QGC. By relying on the QT library, it can support the complete flight control and mission planning of any UAV with the MAVLink protocol. In conjunction with the Ardupilot-driven UAV flight control system, python code is used to call the UAV control, and then a maneuvering avoidance distance experiment is performed; the experiment shows that the horizontal avoidance distance obtained in this embodiment can be used as a safety interval to avoid UAV collisions; the relevant experimental data are shown in Table 1.

[0051] Table 1

[0052]

[0053] For the scenario of two-aircraft avoidance, this embodiment combines the horizontal speed, acceleration, horizontal wind speed and the time to correct the route when encountering horizontal wind of the first UAV and the second UAV to obtain the flight technical error, and combines the navigation performance error to obtain the total error distance of the first UAV and the second UAV; on this basis, this embodiment further combines the maximum turning angle of the first UAV and the second UAV to obtain the horizontal avoidance distance of the first UAV and the second UAV, that is, the horizontal safety interval of the first UAV and the second UAV. The horizontal safety interval obtained in this embodiment is the safety interval between the first UAV and the second UAV in the horizontal direction. Compared with the horizontal safety interval obtained according to the simulation or collision model in the prior art, the horizontal safety interval obtained in this embodiment is determined according to the actual flight scene of the first UAV and the second UAV, and has higher accuracy. The horizontal safety interval obtained in this embodiment is used as a reference for the first UAV and the second UAV to avoid collision in the horizontal direction, which can reduce the hidden danger of collision between the first UAV and the second UAV in the horizontal direction.

[0054] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will also be appreciated by those skilled in the art that various modifications may be made to the embodiments without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A method for handling double aircraft avoidance, characterized in that: The method includes the following steps: S100. Obtain the horizontal speed V1 of the first drone and the horizontal speed V2 of the second drone; S200. If V1 > V2, then determine V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 < V2, then determine V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE; V3 is the average wind speed in the horizontal direction at the positions of the first drone and the second drone, t1 and t2 are the times for the first drone and the second drone to correct the flight path when encountering wind with a magnitude of V3 in the horizontal direction respectively, and a1 and a2 are the accelerations of the first drone and the second drone in the horizontal direction respectively; S300, obtaining the total error distance PCA according to FTE, the radius r1 of the first UAV and the radius r2 of the second UAV; PCA=(FTE 2 +NSE 2 ) 0.5 +r1+r2, NSE is the preset navigation performance error; S400. Obtain the maximum turning angle θ1 of the first drone and the maximum turning angle θ2 of the second drone; S500. Obtain the turning radius R1 of the first drone according to θ1 and V1; S600. Obtain the turning radius R2 of the second drone according to θ2 and V2; S700, obtaining the horizontal avoidance distance d between the first UAV and the second UAV according to PCA, θ1, θ2, R1 and R2 avoid ;d avoid =(((V1×sin(θ1)+V2×sin(θ2))×t0) 2 +(PCA+R1×θ1+R2×θ2) 2 ) 0.5 , t0 is the preset avoidance time.

2. The method for dual aircraft avoidance according to claim 1, characterized in that: S200 further includes: if V1 = V2 and a1 > a2, then determine V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 = V2 and a1 < a2, then determine V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE.

3. The method for dual aircraft avoidance according to claim 1, characterized in that: S200 further includes: if V1 = V2, a1 = a2 and t1 ≥ t2, then determine V3×t1+(V1×V1) / (2×a1) as the flight technical error FTE; if V1 = V2, a1 = a2 and t1 < t2, then determine V3×t2+(V2×V2) / (2×a2) as the flight technical error FTE.

4. The method for dual aircraft avoidance according to claim 1, characterized in that: V3 satisfies the following relationship: V3=(V 3,1 +V 3,2 ) / 2, where V 3,1 and V 3,2 are the horizontal wind speeds at the locations of the first UAV and the second UAV respectively.

5. The method for dual aircraft avoidance according to claim 1, characterized in that: R1 satisfies the following relationship: R1=(V1×V1) / (g×((LF1×LF1-1) 0.5 )'), where g is the acceleration due to gravity, ( )' is the derivative, LF1 is the load factor of the first UAV, LF1=1 / (cos(θ1))'.

6. The method for dual aircraft avoidance according to claim 1, characterized in that: R2 satisfies the following relationship: R2=(V2×V2) / (g×((LF2×LF2-1) 0.5 )'), where g is the acceleration due to gravity, ( )' is the derivative, LF2 is the load factor of the second UAV, LF2=1 / (cos(θ2))'.

7. The method for dual aircraft avoidance according to claim 1, characterized in that: The NSE is 9.14 meters.

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