A control method and system for the random flight mode of a rotary-wing unmanned aerial vehicle

Abstract

The present invention belongs to the field of UAV route planning, and specifically discloses a control method and system for the random flight mode of a rotor UAV. It includes: a hovering flight mode, with the best monitoring point as the origin of polar coordinates, and a random function is used to plan the random flight points of the UAV in real time, so that the UAV performs the monitoring task under random flight around the origin of polar coordinates; a following flight mode, by identifying the distance between the UAV and the tracking target, and a random function is used in real time to plan the random flight points of the UAV in real time, so as to adjust the relative distance between the UAV and the following target, making the UAV fly randomly; a target flight mode, setting the flight end point of the UAV, the UAV automatically plans the initial route according to satellite navigation and the environment, and based on the initial route and the real-time environment, a random function is used to regenerate the random flight points of the UAV, so as to generate the random flight route of the UAV in the target flight mode. The present invention has the characteristics of strong self-defense ability.

Description

Technical Field

[0001] The present invention belongs to the technical field of unmanned aerial vehicle route planning, and more specifically, relates to a control method and system for the random flight mode of a rotor unmanned aerial vehicle. Background Art

[0002] With the development and maturity of unmanned aerial vehicle technology and the continuous improvement of intelligence level, unmanned aerial vehicles will become the leaders of the future sky and the main equipment of the armed forces of various countries in the world, and have great combat potential on the future battlefield. In the modern war of informatization, networking and systematization, it has become an inevitable trend to rely on unmanned aerial vehicles to perform intelligence reconnaissance, battlefield strikes and other combat tasks.

[0003] At the same time, anti-unmanned aerial vehicle defense technology has been basically mature. The main technologies of the current anti-unmanned aerial vehicle defense system include signal interference, laser strike, physical countermeasures and other means. In terms of countermeasures against military unmanned aerial vehicles, laser strike and physical countermeasures are the main technical means. Therefore, it is necessary to further improve the self-defense ability of unmanned aerial vehicles. Chinese Patent CN111813144A discloses a multi-unmanned aerial vehicle collaborative route planning method based on an improved flock algorithm, which is a method for planning the collaborative routes of multiple unmanned aerial vehicles in a complex three-dimensional space based on the improved flock algorithm. Its flight route is determined by the leading unmanned aerial vehicle, and other unmanned aerial vehicles move and follow the leading unmanned aerial vehicle according to the improved flock algorithm, so its flight route can be predicted and its self-defense ability is poor.

[0004] Based on the above defects and deficiencies, there is an urgent need in this field to propose a random flight mode for unmanned aerial vehicles, which generates random flight routes according to different flight tasks and flight environments to avoid the attack of anti-unmanned aerial vehicle systems and improve the self-defense ability of unmanned aerial vehicles. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement requirements of the prior art, the present invention provides a control method and system for the random flight mode of a rotor unmanned aerial vehicle. By combining the characteristics of the unmanned aerial vehicle itself and the characteristics of its self-defense path planning, a control method for generating random flight routes according to different flight tasks and flight environments is designed accordingly, and specific calculations are performed on the hovering flight mode, the random flight mode under following flight and the random flight points in the target flight mode in its control method, and random flight routes in three flight modes are generated randomly, so that the unmanned aerial vehicle generates a random flight route under the condition of completing the established task to avoid the attack of the anti-unmanned aerial vehicle system, and has the characteristics of simple calculation, fast response speed and strong self-defense ability.

[0006] To achieve the above object, the present invention proposes a random flight mode and control method for a rotor unmanned aerial vehicle, including a hovering flight mode, a following flight mode and a target flight mode, wherein,

[0007] In the hovering flight mode, the optimal monitoring point is used as the origin of the polar coordinates, and a random function is used to plan the random flight points of the UAV in real time, so that the UAV performs the monitoring task under random flight around the origin of the polar coordinates;

[0008] In the following flight mode, by identifying the distance between the UAV and the tracking target, and a random function is used in real time to plan the random flight points of the UAV in real time, so as to adjust the relative distance between the UAV and the following target, so that the UAV maintains a random flight at an effective following distance from the tracking target;

[0009] In the target flight mode, the flight end point of the UAV is set. The UAV automatically plans the initial route according to satellite navigation and the environment. Based on the initial route and the real-time environment, a random function is used to regenerate the random flight points of the UAV, so as to generate the random flight route of the UAV in the target flight mode.

[0010] As a further preference, the random function is the rand random function or a custom random function.

[0011] As a further preference, the hovering flight mode includes a planar random flight trajectory planning method and a three-dimensional space random flight trajectory planning method.

[0012] As a further preference, the planar random flight trajectory planning method is specifically as follows:

[0013] Using the optimal monitoring point as the origin of the polar coordinates, the UAV starts flying from the origin of the polar coordinates, and a random function is used to plan the next random flight point The polar coordinate value of this point is ρ1 = 5 × rand, Taking the random flight point as the starting point, a random function is used to generate the next random flight point In this way, the path of the UAV's random flight is continuously generated;

[0014] The three-dimensional space random flight trajectory planning method is specifically as follows:

[0015] Using the optimal monitoring point as the origin of the polar coordinates, the UAV starts flying from the origin of the polar coordinates, and a random function is used to plan the next random flight point The spherical coordinate value of this point is ρ1 = 5 × rand, θ1 = 360 × rand. Taking the random flight point as the starting point, a random function is used to generate the next random flight point In this way, the path of the UAV's random flight is continuously generated.

[0016] As a further preference, in the following flight mode, the calculation model of the relative distance between the UAV and the following target is as follows:

[0017]

[0018] Among them, L is the effective following distance;

[0019] In the following flight mode, image recognition or signal strength recognition is used to recognize the distance between the UAV and the tracking target.

[0020] As a further preference, in the target flight mode, the flight end point of the UAV is set, and the UAV automatically plans the initial route according to satellite navigation and the environment. Taking the UAV flight starting point as the starting point, an initial point d is intercepted on the initial route. The path length between the starting point and the initial point d is the flight step length. Centered on the initial point d, a random flight point is generated by using a random function The polar coordinate value of this point is ρ2 = 5 × rand, Taking the initial point d as the starting point, an initial point e is intercepted on the initial route. The path length between the starting point and the initial point d is the flight step length. Centered on the initial point e, a random flight point is generated by using a random function The polar coordinate value of this point is ρ3 = 5 × rand, In this way, until the path between the initial point and the end point is less than the flight step length, the UAV flies from the last random flight point to the end point, thereby generating a random flight route of the UAV.

[0021] As a further preference, the flight step length is determined according to the maximum level flight speed, maximum climb speed and flight direction of the UAV to ensure that the UAV can reach the next initial point from the previous initial point within 0.5 s.

[0022] As a further preference, the hovering flight mode, following flight mode and target flight mode all include an obstacle avoidance method, that is, when the UAV flies from the current random flight point to the next random flight point, if the UAV detects an obstacle within the motion safety range, the UAV abandons the next random flight point and takes the current position of the UAV as the starting point, and a random flight point of the UAV is regenerated by using a random function.

[0023] Generally speaking, compared with the prior art through the above technical solutions conceived by the present invention, the following technical advantages are mainly possessed:

[0024] 1. In combination with the characteristics of the drone itself and its own defense path planning features, the present invention correspondingly designs a control method for generating a random flight route according to different flight tasks and flight environments, and specifically calculates the random flight points in the hover flight mode, the random flight mode under following flight, and the target flight mode in its control method, and randomly generates random flight routes in the three flight modes, so that the drone can generate a random flight route under the condition of completing the established task to avoid the attack of the anti-drone system, and has the characteristics of simple calculation, fast response speed, and strong self-defense ability.

[0025] 2. The present invention generates a random flight route according to different flight tasks and flight environments to improve the self-defense ability of the drone. Among them, the random flight routes in the three flight modes are all generated by random functions, which can effectively reduce the risk of being shot down.

[0026] 3. In the hover flight mode of the present invention, taking the best monitoring point as the polar coordinate 0 point, the drone executes the monitoring task under random flight around the 0 point. At the same time, a random flight trajectory is generated by a random function within a plane or spherical range during the flight process, so that the drone can maintain a random flight path within a small range, can complete the monitoring task, and at the same time, due to its unpredictable trajectory, it is difficult to be tracked.

[0027] 4. In the following flight mode of the present invention, the flight path of the drone is changed by randomly adjusting the relative distance between the drone and the following target, and at the same time, the following distance is randomly adjusted by using a random function, so that the drone flies while maintaining a certain spatial relative position with the following target, and at the same time, due to its unpredictable trajectory, it is difficult to be tracked.

[0028] 5. In the target flight mode of the present invention, the flight end point of the drone is set, and the drone automatically plans the initial route according to satellite navigation and the environment. Based on the initial route and the real-time environment, a random function is used to regenerate the random flight points of the drone to generate the random flight route of the drone in the target flight mode. In this process, the flight step length is determined according to the flight speed and flight direction, so that while the drone maintains a random flight path, it is ensured that the drone can reach the next random flight point within 0.5 s. In this way, while ensuring that the drone tracks the target, the self-defense ability of the drone is improved. Description of the Drawings

[0029] Figure 1 is a flowchart of a control method for a random flight mode of a rotor drone according to a preferred embodiment of the present invention;

[0030] Figure 2 is a schematic diagram of plane random flight trajectory planning in a control method for a random flight mode of a rotor drone according to a preferred embodiment of the present invention;

[0031] Figure 3 It is a schematic diagram of the three-dimensional space random flight trajectory planning in a control method for the random flight mode of a rotor unmanned aerial vehicle according to a preferred embodiment of the present invention;

[0032] Figure 4 It is a schematic diagram of the random flight trajectory planning in the following flight mode in a control method for the random flight mode of a rotor unmanned aerial vehicle according to a preferred embodiment of the present invention;

[0033] Figure 5 It is a schematic diagram of the initial route planning in the target flight mode in a control method for the random flight mode of a rotor unmanned aerial vehicle according to a preferred embodiment of the present invention;

[0034] Figure 6 It is a schematic diagram of the random flight trajectory planning in the target flight mode in a control method for the random flight mode of a rotor unmanned aerial vehicle according to a preferred embodiment of the present invention. Detailed implementation manners

[0035] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] As Figure 1 shown, a control method for the random flight mode of a rotor unmanned aerial vehicle provided by an embodiment of the present invention includes a hovering flight mode, a following flight mode, and a target flight mode. Random flight routes in the three flight modes are generated through a specific function to avoid attacks from anti-unmanned aerial vehicle systems, and it has low cost and is easy to implement.

[0037] Specifically, in the hovering flight mode, the best monitoring point is used as the origin of the polar coordinates, and a random function is used to plan the random flight points of the unmanned aerial vehicle in real time, so that the unmanned aerial vehicle performs the monitoring task under random flight around the origin of the polar coordinates. The hovering flight mode includes a planar random flight trajectory planning method and a three-dimensional space random flight trajectory planning method.

[0038] As Figure 2 shown, the planar random flight trajectory planning method is as follows: The best monitoring point is used as the polar coordinate 0 point, and the unmanned aerial vehicle performs the monitoring task under random flight around the 0 point. The method for generating the random flight trajectory in this mode is as follows: The unmanned aerial vehicle starts flying from the polar coordinate 0 point and plans the next random flight point The polar coordinate value is ρ1 = 5×rand, Plan the next random flight point The polar coordinate value is ρ2 = 5×rand, And so on, continuously generate random polar coordinate points, that is, random flight points, and maintain a random flight path. In this mode, with the best monitoring point as the origin of the polar coordinates, the UAV starts flying from the origin of the polar coordinates, uses a random function to plan random flight points, and while completing the monitoring task, randomly generates the flight path of the UAV, making its path unpredictable to avoid the attack of the anti-UAV system.

[0039] As Figure 3 shown, the three-dimensional space random flight trajectory planning method is as follows: with the best monitoring point as the origin of the polar coordinates, the UAV starts flying from the origin of the polar coordinates, and uses a random function to plan the next random flight point The spherical coordinate values of this point are ρ1 = 5×rand, θ1 = 360×rand. Starting from the random flight point as the starting point, use a random function to generate the next random flight point In this way, continuously generate the path that constitutes the random flight of the UAV.

[0040] In these two random flight trajectory planning methods, an obstacle avoidance module is also integrated on the UAV. The obstacle avoidance module is used to implement the obstacle avoidance method of the UAV, that is, when the UAV flies from the current random flight point P1 to the next random flight point P2, if the UAV detects that it will touch an obstacle within the safe range of the UAV's movement along this path, then at this time, the obstacle avoidance module triggers the UAV flight mode control module, and the UAV abandons the random flight point P2, and takes the current position of the UAV as the starting point, and uses a random function to regenerate the random flight point of the UAV. In the preferred embodiment of the present invention, the path distance from the random flight point P1 to the random flight point P2 satisfies the following conditions: determined according to the maximum level flight speed, maximum climbing speed and flight direction of the UAV, so as to ensure that the UAV can reach the next random flight point within the specified time. When the obstacle avoidance module is triggered, it is also necessary to ensure that the UAV reaches the next random flight point from the current position within the specified time.

[0041] At the same time, in the preferred embodiment of the present invention, when the UAV flies to a specified random flight point, it stays for a specified long time to perform corresponding tasks, such as surveillance shooting tasks. Generally speaking, a random function is used to determine the random flight point for the specified stay, that is, the specified random flight point for the stay is also uncertain.

[0042] As Figure 4As shown, in the follow - flight mode, by identifying the distance between the drone and the tracking target, and in real - time using a random function to plan the random flight points of the drone in real - time, so as to adjust the relative distance between the drone and the following target, enabling the drone to perform random flight while maintaining an effective following distance from the tracking target. Specifically, the follow - flight mode involves flying with a certain spatial relative position to the following target. The follow - flight is through closed - loop control, and tracks the target for flight through image recognition or signal strength recognition. Therefore, in this mode, the flight path of the drone can be changed by randomly adjusting the relative distance between the drone and the following target.

[0043] Combined with the embodiments, the method for generating a random flight trajectory is as follows: Let the effective following distance of the drone in the system be L, and the calculation model for the relative distance between the drone and the following target is as follows:

[0044]

[0045] where L is the effective following distance.

[0046] In the embodiments, the follow - system based on signal strength can adjust the following distance by adjusting the received signal strength threshold; the follow - system based on visual recognition can adjust the following distance by adjusting the imaging size.

[0047] As Figure 5 shown, in the target - flight mode, set the flight end - point of the drone. The drone automatically plans the initial route according to satellite navigation and the environment. Based on the initial route and the real - time environment, use a random function to regenerate the random flight points of the drone, so as to generate the random flight route of the drone in the target - flight mode. In the target - flight mode, set the flight end - point of the drone. The drone automatically plans the initial route according to satellite navigation and the environment. As Figure 6 shown, taking the flight starting - point of the drone as the starting - point, intercept the initial point d on the initial route. The path length between the starting - point and the initial point d is the flight step. Taking the initial point d as the center, construct the tangent of the initial route at the initial point d, construct the vertical plane of the above - mentioned tangent at the initial point d. In this vertical plane, taking the initial point d as the polar - coordinate origin, use a random function to generate a random flight point The polar - coordinate value of this point is ρ2 = 5×rand, Taking the initial point d as the starting - point, intercept the initial point e on the initial route. The path length between the starting - point and the initial point d is the flight step. Taking the initial point e as the center, construct the tangent of the initial route at the initial point e, construct the vertical plane of the above - mentioned tangent at the initial point e. In this vertical plane, taking the initial point e as the polar - coordinate origin, use a random function to generate a random flight point The polar - coordinate value of this point is ρ3 = 5×rand, In this way, until the path between the starting point and the ending point is less than the flight step length, the UAV flies from the last random flight point to the ending point, thereby generating a random flight route of the UAV.

[0048] In a preferred embodiment of the present invention, in the target flight mode, if the UAV detects a random flight point to the random flight point on the path, within the motion safety range of the UAV, an obstacle will be touched, then at this time the obstacle avoidance module triggers the UAV flight mode control module. At this time, the UAV abandons the random flight point in the vertical plane of the tangent line where the starting point e is located, and randomly generates again using a random function

[0049] In an embodiment of the present invention, the flight step length is determined according to the maximum level flight speed, maximum climbing speed and flight direction of the UAV, so as to ensure that the UAV can reach the next starting point from the previous starting point within 0.5 s.

[0050] The present invention also provides a random flight mode control system for a rotor UAV to implement the above method, including a UAV and a random flight control module, an obstacle avoidance module, a signal transceiver module, and a controller integrated on the UAV. Among them, the controller is communicatively connected to the random flight control module, the obstacle avoidance module, the signal transceiver module, and the controller. The random flight control module is used to control the random flight mode of the UAV. Of course, in a preferred embodiment of the present invention, an image recognition module is further included, and the image recognition module is communicatively connected to the controller for recognizing and tracking the graphics of the target.

[0051] Generally, a UAV has three flight modes: hovering flight, following flight, and target flight. Random flight routes in the three flight modes are generated through a specific function. In the following embodiments, the maximum level flight speed of the UAV is 20 m / s, and the maximum climbing speed is 4 m / s. In the embodiments, the conventional random function rand is used, and the returned random number is a uniformly distributed random real number greater than or equal to 0 and less than 1.

[0052] 1. Hovering flight mode

[0053] In the hovering flight mode, the UAV is in a certain fixed position, and it is extremely vulnerable to attack in the hovering mode.

[0054] The method for planning a random flight path in a plane is as follows: Taking the best monitoring point as the polar coordinate 0 point, as Figure 2 shown, the UAV performs a monitoring task under random flight around the 0 point.

[0055] The method for generating a random flight trajectory is as follows: The UAV starts flying from the polar coordinate 0 point and plans the next random flight point The polar coordinate value is ρ1 = 5 × rand, Plan the next random flight point The polar coordinate value is ρ2 = 5 × rand, And so on, continuously generate random polar coordinate points to maintain the random flight path.

[0056] Plan a random flight path in three-dimensional space as follows: Take the best monitoring point as the polar coordinate 0 point, as Figure 3 shown, the unmanned aerial vehicle performs the monitoring task under random flight around the 0 point.

[0057] The method for generating a random flight trajectory is as follows: The unmanned aerial vehicle starts flying from the polar coordinate 0 point and plans the first random flight point The spherical coordinate value is ρ1 = 5 × rand, θ1 = 360 × rand. Plan the second random flight point The polar coordinate point is ρ2 = 5 × rand, θ2 = 360 × rand. And so on, continuously generate random spherical coordinate points to maintain the random flight path.

[0058] In addition, it can be set to stay at the planned point for 0.5 s for monitoring and shooting.

[0059] 2. Random flight mode under following flight

[0060] The following flight mode is to fly while maintaining a certain spatial relative position with the following target. The following flight is through closed-loop control and tracks the target for flight through image recognition or signal strength recognition. Therefore, in this mode, the flight path of the unmanned aerial vehicle can be changed by randomly adjusting the relative distance between the unmanned aerial vehicle and the following target, as Figure 4 shown.

[0061] Combined with the embodiment, the method for generating a random flight trajectory is as follows: Let the effective following distance of the unmanned aerial vehicle in the system be L, and randomly adjust the following distance

[0062] In the embodiment, the following system based on signal strength can adjust the following distance by adjusting the received signal strength threshold; the following system based on visual recognition can adjust the following distance by adjusting the imaging size.

[0063] 3. Target flight mode

[0064] The target flight mode is to set the flight end point of the unmanned aerial vehicle, and the unmanned aerial vehicle automatically plans the route according to satellite navigation and the environment. Plan a random flight route based on the planned route and the real-time environment.

[0065] Combined with the embodiment, the unmanned aerial vehicle flies from point a, through point b, to point c. The normal flight route is as Figure 5 shown.

[0066] The method for generating a random flight trajectory is as follows Figure 6 as shown

[0067] The unmanned aerial vehicle takes off from point a, plans the first random flight point d1, determines the flight step length λ1 according to the flight speed and flight direction, obtains point d along the original flight route, the length of line segment ad is equal to λ1, then generates a plane d perpendicular to the ad line with point d as the center, establishes a polar coordinate system with point d as the center, and randomly generates The polar coordinate value is ρ1 = 5 × rand, plans the second random flight point e1, determines the flight step length λ2 according to the flight speed and flight direction, obtains point e along the original flight route, the length of line segment de is equal to λ2, then generates a plane e perpendicular to the de line with point e as the center, establishes a polar coordinate system with point e as the center, and randomly generates polar coordinate points, the polar coordinate value is ρ2 = 5 × rand, And so on, continuously generate random coordinate points to maintain the random flight path. The flight step length λ is determined by the maximum level flight speed and the maximum climbing speed of the unmanned aerial vehicle to ensure that the unmanned aerial vehicle can reach within 0.5 s

[0068] In the above embodiments, the random function uses the rand random function. However, the rand random function is a publicly available function. To prevent cracking, a custom random function can also be used, such as a triangular random function. For example, f(x) = arcsin(rand), and the assignment interval of this random function is

[0069] In an embodiment of the present invention, the random function can also be used to customize a sufficiently long string of random numbers by means of a look-up table and then used in a loop. For example, 1024 random 8-bit unsigned numbers can be stored (only occupying 1 KB of storage space), and the numerical range of each number is 0 to 255. If such a large numerical range is not required, an 8-bit unsigned number can be read by bits to generate two numbers for the first four bits and the last four bits respectively, with the number range of 0 to 16. Then 2048 random numbers can be stored in 1 KB of storage space

[0070] During the flight, it is still necessary to use the obstacle avoidance means of the unmanned aerial vehicle itself to avoid obstacles during the random flight

[0071] Those skilled in the art can easily understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention

Claims

1. A control method for the random flight mode of a rotor UAV, characterized in that, Including a hover flight mode, a follow - up flight mode, and a target flight mode. Among them, In the hover flight mode, taking the best monitoring point as the origin of polar coordinates, and using a random function to plan the random flight points of the drone in real - time, so that the drone performs monitoring tasks under random flight around the origin of polar coordinates; In the follow - up flight mode, by identifying the distance between the drone and the tracking target, and using a random function in real - time to plan the random flight points of the drone in real - time, so as to adjust the relative distance between the drone and the following target, making the drone perform random flight at an effective following distance from the tracking target; In the target flight mode, setting the end point of the drone's flight, the drone automatically plans the initial route according to satellite navigation and the environment. Based on the initial route and the real - time environment, using a random function to regenerate the random flight points of the drone, so as to generate the random flight route of the drone in the target flight mode; The hover flight mode includes a planar random flight trajectory planning method and a three - dimensional space random flight trajectory planning method; The specific method for planar random flight trajectory planning is as follows: Taking the optimal monitoring point as the origin of polar coordinates, the drone starts flying from the origin of polar coordinates, and uses a random function to plan the next random flight point The polar coordinate value of this point is ρ1 = 5×rand, Taking the random flight point as the starting point, use a random function to generate the next random flight point In this way, continuously generate the path that constitutes the random flight of the drone; The specific method for three - dimensional space random flight trajectory planning is as follows: Taking the optimal monitoring point as the origin of polar coordinates, the drone starts flying from the origin of polar coordinates and uses a random function to plan the next random flight point The spherical coordinate value of this point is ρ1 = 5 × rand, θ1 = 360 × rand, taking the random flight point as the starting point, and using a random function to generate the next random flight point In this way, the path of the drone's random flight is continuously generated; where is the spherical coordinate value of the random flight point P1, is the spherical coordinate value of the random flight point P2.

2. The control method for the random flight mode of a rotor UAV according to claim 1, characterized in that, The random function is the rand random function or a custom - defined random function.

3. The control method for the random flight mode of a rotor UAV according to claim 1, characterized in that, In the follow - up flight mode, the calculation model of the relative distance between the drone and the following target is as follows: Among them, L is the effective following distance, and rand is the random function; The random function is a trigonometric function, and the assignment interval of the trigonometric function is Or, The random function is to customize a sufficiently long string of random numbers by the look - up table method and then use them cyclically. The random numbers are 1024 random 8 - bit unsigned numbers, and the value range of each number is 0 - 255, or the digital range of each number is 0 - 16; In the follow - up flight mode, image recognition or signal strength recognition is used to identify the distance between the drone and the tracking target.

4. The control method for the random flight mode of a rotor UAV according to claim 1, characterized in that, In the target flight mode, the end point of the UAV flight is set. The UAV automatically plans the initial route according to satellite navigation and the environment. Starting from the starting point of the UAV flight, an initial point d is intercepted on the initial route. The path length between the starting point and the initial point d is the flight step. Centered on the initial point d, a random flight point is generated using a random function The polar coordinate value of this point is ρ2 = 5×rand, Starting from the initial point d, an initial point e is intercepted on the initial route. The path length between the starting point and the initial point e is the flight step. Centered on the initial point e, a random flight point is generated using a random function The polar coordinate value of this point is ρ3 = 5×rand, In this way, until the path between the initial point and the end point is less than the flight step, the UAV flies from the last random flight point to the end point, thus generating a random flight route of the UAV, where is the polar coordinate value of the random flight point d1 in the polar coordinate system established with point d as the center, is the polar coordinate value of the random flight point e1 in the polar coordinate system established with point e as the center.

5. The control method for the random flight mode of a rotor UAV according to claim 4, characterized in that, The flight step size is determined according to the maximum level flight speed, maximum climbing speed, and flight direction of the drone, so as to ensure that the drone can reach the next initial point from the previous initial point within 0.5 s.

6. The control method for the random flight mode of a rotor UAV according to any one of claims 1-5, characterized in that, The hover flight mode, follow - up flight mode, and target flight mode all include an obstacle avoidance method, that is, when the drone flies from the current random flight point to the next random flight point, if the drone detects an obstacle within the motion safety range, the drone abandons the next random flight point and uses the current position of the drone as the starting point to regenerate the random flight points of the drone using a random function.

7. A control system for the random flight mode of a rotor UAV, which is used to implement the random flight mode and control method of a rotor UAV according to any one of claims 1-5.

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