Rotor UAV collision method, device, UAV and storage medium

Abstract

The present application discloses a rotorcraft UAV impact method, device, UAV and storage medium for performing target impact using the flight control system on the UAV in the absence of GPS signals. The method comprises: determining the total horizontal acceleration of the UAV based on the tilt angle of the UAV in each control cycle and a predetermined maximum horizontal velocity, and determining a horizontal velocity estimate based on the total horizontal acceleration; determining the missile-target line-of-sight unit vector in the north-east coordinate system based on the parameters of the camera on the UAV and the attitude of the UAV, and determining the line-of-sight azimuth and line-of-sight altitude angle based on the missile-target line-of-sight unit vector; and achieving the UAV impact on the target according to proportional guidance control and / or speed tracking control based on at least one of the horizontal velocity estimate, line-of-sight azimuth or line-of-sight altitude angle. The above scheme enables accurate impact on the target even in the absence of GPS signals.

Description

Technical Field

[0001] The present application relates to the field of drone navigation and control technology, and in particular to a rotor drone collision method, device, drone, and storage medium. Background Art

[0002] With the development of intelligent control theory and technology, drones are gaining widespread military applications, such as for reconnaissance and strike missions. Low-cost, easy-to-use, and portable attack rotary-wing drones are a promising option. However, existing rotary-wing drone flight control systems only function properly in the presence of a GPS signal. Furthermore, many rotary-wing drones lack pods, equipped only with inexpensive strapdown cameras. Therefore, how to achieve target impact in the absence of GPS signals and relying solely on strapdown cameras is a pressing issue. Summary of the Invention

[0003] In view of the above problems, the present application is proposed to provide a rotorcraft UAV collision method, device, UAV and storage medium that overcome the above problems or at least partially solve the above problems.

[0004] According to one aspect of the present application, a rotorcraft UAV impact method is provided for impacting a target using a flight control system on the UAV in the absence of a GPS signal. The method comprises:

[0005] determining a total horizontal acceleration of the UAV based on a tilt angle of the UAV in each control cycle and a predetermined maximum horizontal velocity, and determining a horizontal velocity estimate based on the total horizontal acceleration;

[0006] Based on the parameters of the camera on the UAV and the attitude of the UAV, the unit vector of the missile-target line of sight in the north-east coordinate system is determined, and the azimuth and elevation angle of the line of sight are determined based on the unit vector of the missile-target line of sight.

[0007] Based on at least one of the horizontal velocity estimate, the line of sight azimuth angle, or the line of sight elevation angle, the UAV is brought into collision with the target according to proportional guidance control and / or speed tracking control.

[0008] In some embodiments, determining a total horizontal acceleration of the drone based on a tilt angle of the drone in each control cycle and a predetermined maximum horizontal velocity, wherein determining a horizontal velocity estimate based on the total horizontal acceleration includes:

[0009] Determine the horizontal acceleration caused by the tilt of the drone based on the relationship between the acceleration of gravity and the tilt angle of the drone;

[0010] According to the functional relationship between the tilt angle and the maximum horizontal speed of the UAV determined in advance through testing, the maximum horizontal speed of the UAV in each control cycle is estimated;

[0011] Based on the relationship between the acceleration caused by air resistance and the current tilt angle, horizontal velocity, and maximum horizontal velocity of the UAV, the acceleration caused by air resistance is expressed as horizontal acceleration, and the total horizontal acceleration of the UAV is determined.

[0012] The estimated value of the horizontal velocity of the current control cycle is obtained by integrating the total horizontal acceleration and combining it with the horizontal velocity of the previous control cycle.

[0013] In some embodiments, causing the drone to impact a target using proportional guidance control and / or speed tracking control based on at least one of a horizontal velocity estimate, a line of sight azimuth, or a line of sight elevation includes:

[0014] Based on the control of the vertical speed of the UAV, the impact control of the UAV on the target is divided into multiple stages, including: the stage of yaw-turning the nose toward the target, the stage of running to the intersection point to control the elevation angle of the line of sight within the impact range of the target, the stage of speed tracking and guidance of the target, and / or the stage of proportional guidance.

[0015] In some embodiments, the control logic executed during the phase of steering the nose yaw to the target includes at least one of the following:

[0016] The desired value of the yaw angle of the UAV is controlled to gradually approach the line of sight azimuth value, so that the UAV's nose turns towards the target direction;

[0017] The desired value of the pitch angle of the drone is controlled to gradually approach zero;

[0018] The expected vertical velocity of the drone is controlled to be zero;

[0019] The expected value of the roll angle of the drone is controlled to be zero.

[0020] In some embodiments, the control logic executed during the run-to-joint phase to control the sight elevation angle within the impactable range of the target includes at least one of the following:

[0021] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0022] The control of the desired value of the pitch angle of the drone includes: if the sight elevation angle is greater than zero, and the height of the target is greater than the height of the drone, then the desired value of the pitch angle is controlled to tend toward or even be zero; if the sight elevation angle is less than a first threshold, then the desired value of the pitch angle is controlled to tend toward or even be zero; if the sight elevation angle is between zero and a second threshold, then the desired value of the pitch angle is controlled to tend toward or even be equal to the sight elevation angle, and the drone is controlled to fly upward simultaneously;

[0023] The control of the expected vertical speed of the UAV includes: multiplying the difference between the optimal trajectory angle and the current line of sight elevation angle by a proportional term to obtain the expected line of sight elevation rate, and adjusting the expected vertical speed so that the current line of sight elevation rate gradually approaches the expected line of sight elevation rate: when the expected line of sight elevation rate is greater than zero, controlling the expected vertical speed to make the UAV descend; when the expected line of sight elevation rate is less than zero, controlling the expected vertical speed to make the UAV climb.

[0024] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0025] In some embodiments, the control logic executed during the stage of performing speed tracking guidance on the target includes at least one of the following:

[0026] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0027] The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight.

[0028] Controlling the expected vertical speed value of the UAV includes: determining the expected vertical speed value according to the product of the tangent value of the negative value of the sight elevation angle and the estimated horizontal speed value;

[0029] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0030] In some embodiments, the control logic executed in the proportional guidance phase includes at least one of the following:

[0031] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0032] The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight.

[0033] The expected vertical speed of the UAV is obtained by multiplying the expected vertical speed angles of the previous control cycle by the proportional term of the proportional guidance algorithm in the vertical plane, the vertical speed of the missile-target sight line of sight, and the interval between two adjacent control cycles. The expected vertical speed is then determined by multiplying the tangent of the negative value of the expected vertical speed angles of the current control cycle by the estimated horizontal speed.

[0034] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0035] According to another aspect of the present application, a rotorcraft UAV impact device is provided for impacting a target using a flight control system on the UAV in the absence of a GPS signal. The device comprises:

[0036] a horizontal velocity estimation module adapted to determine a total horizontal acceleration of the UAV based on a tilt angle of the UAV in each control cycle and a predetermined maximum horizontal velocity, and to determine a horizontal velocity estimation value based on the total horizontal acceleration;

[0037] The sight angle determination module is suitable for determining the missile-target sight unit vector in the north-east coordinate system based on the parameters of the drone's camera and the drone's attitude, and determining the sight azimuth and sight altitude angle based on the missile-target sight unit vector;

[0038] The target impact control module is adapted to achieve the impact of the UAV on the target according to proportional guidance control and / or speed tracking control based on at least one of the horizontal velocity estimation value, the line of sight azimuth angle or the line of sight elevation angle.

[0039] According to another aspect of the present application, a drone is provided, comprising: a processor and a memory arranged to store computer-executable instructions, wherein when the executable instructions are executed, the processor executes the rotor drone impact method according to any one of the above embodiments.

[0040] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores one or more programs, and when the one or more programs are executed by a processor, the rotor drone impact method according to any one of the above-mentioned methods is implemented.

[0041] From the above, it can be seen that according to the rotor UAV impact method disclosed in the present application, the horizontal speed estimate of the UAV is first determined based on the UAV inclination angle and the predetermined maximum speed, and the line of sight azimuth and elevation angle are determined according to the camera parameters and the posture of the UAV. Then, based on the above-determined parameters, the proportional guidance algorithm or the speed tracking control algorithm is used to achieve guidance and control of the UAV, so that the UAV can still achieve accurate impact on the target in the absence of a GPS signal.

[0042] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0044] Figure 1 A schematic flow chart of a rotorcraft UAV impact method according to some embodiments of the present application is shown;

[0045] Figure 2 A schematic diagram of a trajectory of a drone impacting a billboard target according to some embodiments of the present application is shown;

[0046] Figure 3 A multi-perspective schematic diagram of a drone colliding with a billboard target according to some embodiments of the present application is shown;

[0047] Figure 4 A schematic structural diagram of a rotor UAV impact device according to some embodiments of the present application is shown;

[0048] Figure 5 A schematic structural diagram of a UAV flight control system according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0049] The following describes exemplary embodiments of the present application in more detail with reference to the accompanying drawings. Although exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0050] The main concept of the embodiments of this application is that, for rotary-wing drones, impact can be achieved by simply installing an altitude sensor, such as a barometer, in the flight control system, without relying on the presence of a GPS signal in the flight scene. The main steps include estimating horizontal velocity, calculating the line of sight angle, and then using proportional guidance and velocity tracking methods based on these parameters to achieve impact guidance. The strapdown camera on the drone is mounted horizontally on the drone's head, with the camera's optical axis parallel to the drone's x-axis. Throughout the impact process, the drone's pitch and yaw angles are adjusted to ensure that the camera's optical axis is always aligned with the target, that is, the target is always in the center of the camera's frame. The drone's horizontal lateral motion is controlled by adjusting the drone's roll angle. The algorithm of this embodiment controls the drone's vertical and horizontal motion by outputting commands such as the desired values ​​of the yaw angle, pitch angle, roll angle, and vertical velocity to the flight control system.

[0051] The aforementioned impacts include, but are not limited to, striking, aiming, diving, pursuing, guiding, and colliding with targets, and can be used for more than just military purposes. For example, drones can be used to inspect other targets, such as other drones, animals, or to fire ammunition at fire sources. In some specific embodiments, a drone can be used to track and hunt animals. A tranquilizer gun or net gun is mounted on the nose of the drone, and it dives toward the animal. During the dive, the nose of the drone remains aligned with the target, and the muzzle of the gun remains aimed at the target. The net gun or tranquilizer gun can be fired upon entering range, and after firing, the operator can raise the drone and move away.

[0052] Figure 1 A flow chart of a rotorcraft UAV impact method according to one embodiment of the present application is shown. The method can be implemented by a program in the UAV's flight control system. The UAV is provided with a camera and a barometer, and is used to perform target impact using the UAV's flight control system in the absence of a GPS signal. The method includes the following steps:

[0053] Step S110, determining a total horizontal acceleration of the drone based on the tilt angle of the drone in each control cycle and a predetermined maximum horizontal velocity, and determining a horizontal velocity estimate based on the total horizontal acceleration;

[0054] Step S120, based on the parameters of the camera on the UAV and the attitude of the UAV, determining the missile-target line of sight unit vector in the north-east coordinate system, and determining the line of sight azimuth and line of sight elevation angle according to the missile-target line of sight unit vector;

[0055] Specifically, by combining the camera's internal parameters, the camera's installation posture on the drone, the center pixel coordinates of the image recognition frame, and the drone's posture, the "missile-eye line of sight unit vector" in the north-east coordinate system can be calculated. Then, the line of sight azimuth can be calculated based on the "missile-eye line of sight unit vector" and sight height angle After low-pass filtering these two angles (pay attention to the low-pass filtering process In the case of a jump at ±180°), the stable and Then the low-pass filtered and Guide, get the rate of change of the sight angle and .

[0056] Step S130, based on the horizontal velocity estimate, the sight azimuth angle, and the sight elevation angle, the UAV is caused to collide with the target according to proportional guidance control and / or speed tracking. Preferably, the nose of the UAV is always aligned with the target during the collision.

[0057] In combination with this embodiment, the UAV can still track and collide with the target in the absence of a GPS signal, and due to the closed-loop control, the collision accuracy of the target is high.

[0058] In some embodiments, the impact trajectory formed simulates Figure 2 and Figure 3 As shown, Figure 2 The lines in the figure are the trajectory of the drone. Figure 3 The picture on the middle right is the picture taken by the camera, and the upper left is the third-person perspective picture, including the linear flight trajectory.

[0059] In some embodiments, a method for implementing horizontal velocity estimation is provided. The following characters are used in the formula of the horizontal velocity estimation part below:

[0060] - The aircraft's bank angle, which represents the angle between the aircraft's z-axis and the plumb line;

[0061] G - acceleration due to gravity;

[0062] - the horizontal acceleration caused by the horizontal component of the propeller thrust acting on the aircraft, which is caused by the tilt of the aircraft;

[0063] - horizontal acceleration caused by air resistance acting on the aircraft;

[0064] - The horizontal acceleration caused by the air resistance caused by the aircraft's current horizontal speed;

[0065] - the horizontal resultant acceleration of the aircraft;

[0066] - The actual value of the aircraft's current horizontal speed;

[0067] - The maximum horizontal speed that an aircraft can generate at a fixed bank angle;

[0068] - estimated horizontal speed of the aircraft during the current control cycle;

[0069] - The aircraft's current vertical speed, with downward being positive;

[0070] - the estimated horizontal speed of the aircraft during the last control cycle;

[0071] - The time interval between two adjacent control cycles is related to the frame rate of image processing.

[0072] Specifically, the drone's current horizontal velocity is a scalar quantity. If the flight controller is equipped with a GPS module and has a GPS signal, the drone's true horizontal velocity (ground speed) can be directly obtained from the flight controller. If there is no GPS signal, there is no direct observation of the horizontal velocity. However, the horizontal velocity can be estimated based on the drone's pitch angle and vertical velocity.

[0073] Therefore, the total horizontal acceleration of the UAV is determined based on the tilt angle of the UAV in each control cycle and the predetermined maximum horizontal velocity. Determining the horizontal velocity estimate based on the total horizontal acceleration includes:

[0074] Determine the horizontal acceleration caused by the tilt of the drone based on the relationship between the acceleration of gravity and the tilt angle of the drone;

[0075]

[0076] According to the functional relationship between the tilt angle and the maximum horizontal speed of the UAV determined in advance through testing, the maximum horizontal speed of the UAV in each control cycle is estimated;

[0077] Estimate the maximum horizontal velocity using simple or elaborate methods Since the proportional guidance algorithm is a closed-loop control, both methods can achieve good impact effects.

[0078] or

[0079] Based on the relationship between the acceleration caused by air resistance and the current tilt angle, horizontal velocity, and maximum horizontal velocity of the UAV, the acceleration caused by air resistance is expressed as horizontal acceleration, and the total horizontal acceleration of the UAV is determined.

[0080]

[0081] By integrating the total horizontal acceleration and combining it with the horizontal velocity of the previous control cycle, the estimated horizontal velocity of the current control cycle is obtained;

[0082] .

[0083] According to a specific embodiment, when the vertical speed of the drone is 0, the specific derivation process of the formula is as follows:

[0084] make is the tilt angle of the drone. is the modulus of the horizontal acceleration caused by tilt. G is the acceleration due to gravity. The calculation method is:

[0085]

[0086] During fixed-angle flight, as the drone's horizontal speed increases, it generates increasing air resistance. The formula for calculating the horizontal acceleration caused by air resistance is as follows.

[0087] In the following formula is the horizontal acceleration due to air resistance. is the air density. It is the true value of the current horizontal speed of the UAV. is the drag coefficient. A is the frontal area. M is the mass of the drone.

[0088]

[0089] The drone maintains a tilt angle unchanged, when the horizontal speed of the drone accelerates to the maximum horizontal speed hour, and Balance, the drone maintains a constant speed.

[0090]

[0091] because and Positive correlation, and Positive correlation. So one The only corresponding one .

[0092] If the current tilt angle of the drone is , Corresponding Known, the current horizontal speed of the UAV can be , calculate the acceleration caused by the current air resistance .because,

[0093]

[0094]

[0095] So, when and ,as well as Corresponding Knowing this, we can calculate the current horizontal acceleration :

[0096]

[0097] It is known that the initial horizontal velocity is 0. In each control cycle, the horizontal velocity estimate of the previous control cycle is Accumulation The speed change caused , the horizontal speed of each control cycle can be estimated .and will gradually converge to .

[0098] Therefore, each control cycle needs to complete the calculation of the following two formulas to obtain :

[0099]

[0100] .

[0101] It should be noted that It can be obtained by conducting flight tests on various types of drones in advance, including the following two methods: Calculate its corresponding Method:

[0102] 1) Simple basis Calculate its corresponding Method

[0103] Installing a GPS module on the drone allows the GPS to directly observe the drone's horizontal speed, so that the flight control system's horizontal speed, vertical speed, bank angle and other information can be viewed in the flight control log or on the ground station.

[0104] Control the drone to maintain a fixed tilt angle And fly at a fixed altitude, when the horizontal speed value of the drone is stable, a set of and The corresponding relationship.

[0105] Test multiple tilt angles They are listed in tables. For example, the table below is generally obtained based on simulation tests in a simulation environment. Of course, they can also be obtained by testing in a real environment.

[0106]

[0107] Using piecewise function or curve fitting method, a function is obtained according to the above table. This function can calculate the corresponding .Right now .

[0108] 2) Detailed basis Calculate its corresponding Method

[0109] Since the horizontal force of the drone is affected by the vertical speed of the drone Therefore, we can add a dimension to this table. Corresponding to one . Thus a three-dimensional surface function is fitted, namely For example, the table below shows tests for 9 tilt angles corresponding to 3 vertical speeds.

[0110]

[0111] In some embodiments, in step S130, based on the estimated horizontal velocity, the line of sight azimuth, and the line of sight elevation, achieving collision of the drone with the target using proportional guidance control and / or speed tracking includes:

[0112] Based on the control of the vertical speed of the UAV, the impact control of the UAV on the target is divided into multiple stages, including: the stage of yaw-turning the nose toward the target, the stage of running to the intersection point with the elevation angle of the line of sight controlled within the impactable range of the target, the stage of speed tracking and guiding the target, and the stage of proportional guidance.

[0113] In the control logic formula of step S130, - bring" " indicates the estimated value (measured value) of x, without " ” means x is the expected value. Represents the derivative of x. The specific characters have the following meanings:

[0114] - expected value of horizontal lateral acceleration, positive when pointing to the right side of the aircraft;

[0115] - The projection length of the aircraft speed on the horizontal plane (scalar). If there is no GPS, it comes from the estimation method above;

[0116] - The aircraft's vertical speed, with downwards being positive;

[0117] - Azimuth of the sight line between the missile and the target, i.e. the angle between the projection of the sight line on the horizontal plane and the north direction, with the sight line to the east being +90°;

[0118] - The elevation angle of the sight line of sight, that is, the angle between the sight line and the horizontal plane, with the sight line upward being positive;

[0119] - Velocity azimuth, the angle between the projection of the velocity vector on the horizontal plane and the north direction, with the velocity eastward being +90°;

[0120] - Velocity elevation angle, i.e. the angle between the velocity and the horizontal plane, with the velocity being positive upwards;

[0121] - The pitch angle of the aircraft attitude, the aircraft tilts up when it is positive;

[0122] - Roll angle in aircraft attitude angle;

[0123] - The yaw angle of the aircraft attitude, with the nose facing north being 0° and the nose facing east being 90°;

[0124] - Proportional term of the proportional guidance method in the horizontal plane;

[0125] - Proportional term of the proportional guidance method in the vertical plane;

[0126] In some specific embodiments, the control logic executed during the yaw steering phase includes at least one of the following:

[0127] The desired value of the yaw angle of the UAV is controlled to gradually approach the line of sight azimuth value, so that the UAV's nose turns towards the target direction;

[0128] The desired value of the pitch angle of the drone is controlled to gradually approach zero;

[0129] The expected vertical velocity of the drone is controlled to be zero;

[0130] The expected value of the roll angle of the drone is controlled to be zero.

[0131] Specifically, the control logic for the first stage of vertical velocity control: nose yaw steering toward the target object includes:

[0132] a. Expected value of the drone's yaw angle The control logic is as follows:

[0133] = , so that the nose turns towards the target object. Here, the amplitude of the rate of change of the desired yaw angle should be controlled to produce a smooth UAV trajectory.

[0134] b. Expected value of the drone's pitch angle = 0;

[0135] c. Expected vertical speed of the drone = 0;

[0136] d. Expected roll angle Control of φ: φ = 0;

[0137] When the estimated yaw angle of the UAV Estimated sight angle If the difference is less than the threshold, it means that the UAV’s yaw angle is aligned with the target, and the process enters “Vertical Speed ​​Control - Phase 2: Heading for the Handover Point”.

[0138] In some embodiments, the control logic executed during the run-to-joint phase to control the sight elevation angle within the impactable range of the target includes at least one of the following:

[0139] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0140] Controlling the desired value of the pitch angle of the drone includes: if the sight elevation angle is greater than zero, and the height of the target is greater than the height of the drone, controlling the desired value of the pitch angle to be closer to or even zero; if the sight elevation angle is less than a first threshold, and the angle between the sight line and the horizontal plane is too large, controlling the desired value of the pitch angle to be closer to or even zero; if the sight elevation angle is between zero and a second threshold, controlling the desired value of the pitch angle to be closer to or even equal to the sight elevation angle, and controlling the drone to fly upward simultaneously;

[0141] The control of the expected vertical speed of the UAV includes: multiplying the difference between the optimal trajectory angle and the current line of sight elevation angle by a proportional term to obtain the expected line of sight elevation rate, and adjusting the expected vertical speed so that the current line of sight elevation rate gradually approaches the expected line of sight elevation rate: when the expected line of sight elevation rate is greater than zero, controlling the expected vertical speed to make the UAV descend; when the expected line of sight elevation rate is less than zero, controlling the expected vertical speed to make the UAV climb.

[0142] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0143] The logic control of this stage is as follows:

[0144] Since this guidance method relies on In a collision range, between the first threshold of the minimum sight elevation angle and the second threshold of the maximum sight elevation angle. If the impact speed of the drone is greater than the second threshold of the line of sight elevation angle, the speed will be too slow. If the line-of-sight angle threshold is less than the first threshold, the drone will become unstable during a collision due to the excessive tilt angle. The second threshold range for the line-of-sight angle is -12 to -20 degrees, and the first threshold range for the line-of-sight angle is -40 to -30 degrees.

[0145] "Rush to the junction" means, If it is outside the impact range, the vertical speed is controlled so that The process of gradually entering the impactable range.

[0146] a. Expected value of the drone's yaw angle The control logic is as follows:

[0147] In all cases, = ;

[0148] b. Expected value of the drone's pitch angle The control logic is as follows:

[0149] if If it is greater than 0°, that is, the target is at a higher altitude than the drone, then:

[0150] = 0°, the drone will remain horizontal and fly vertically upwards.

[0151] if is less than the first threshold, then: = 0°, the drone will remain horizontal and fly vertically downward.

[0152] if The value is between 0 degrees and the second threshold, then:

[0153] = , at this time the drone will gradually lower its head and fly forward while flying upward.

[0154] c. Expected vertical speed of the drone The control logic is as follows:

[0155] The best trajectory angle is generally the average of the first and second thresholds of the sight line height angle. For example, at -26°, the best trajectory angle is the average of the current sight line height angle. The difference is multiplied by the proportional term (such as 0.2) to obtain the expected value of the line of sight high and low angular rate :

[0156]

[0157] Then adjust the vertical speed setting value by , making the current line of sight high and low angular velocity Gradually approaching .

[0158] Vertical speed control is an integral operation. is the expected value of the vertical velocity in this control cycle. is the expected vertical velocity of the last control cycle. 0.25 is the expected acceleration of climbing or descending, in m / s 2 , you can also fill in other expected acceleration values ​​according to actual conditions. dt is the time interval between two adjacent control cycles, in seconds.

[0159] when When it is greater than 0, it means the drone needs to descend:

[0160] when When it is less than 0, it means the drone needs to climb:

[0161]

[0162] d. Use the proportional guidance method to control the roll angle so that the angular velocity of the horizontal velocity vector is proportional to the azimuth angular velocity of the line of sight. . is the expected value of the horizontal lateral acceleration, which is positive when pointing to the right side of the drone. is the line-of-sight azimuth rate. It is the proportional term of the proportional guidance method in the horizontal plane. is the horizontal velocity estimated above. is the expected value of the pitch angle. is the acceleration due to gravity.

[0163]

[0164]

[0165] Because the target is far away from the drone at this stage and the drone's flight speed is slow, the horizontal line of sight angular rate is very small, resulting in the expected value of the roll angle calculated by the formula being almost 0.

[0166] when After entering the impactable range, the line of sight elevation angle is between the first threshold and the second threshold, that is, it reaches the intersection point, and then enters "Vertical Speed ​​Control-Third Stage: Control Based on Speed ​​Tracking Algorithm".

[0167] In some embodiments, the control logic executed during the stage of performing speed tracking guidance on the target includes at least one of the following:

[0168] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0169] The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight.

[0170] Controlling the expected vertical speed value of the UAV includes: determining the expected vertical speed value according to the product of the tangent value of the negative value of the sight elevation angle and the estimated horizontal speed value;

[0171] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0172] The principle of speed tracking control is to direct the UAV's three-dimensional velocity vector toward the target, thereby tracking the target. The variables based on this control include the estimated horizontal velocity, the line of sight azimuth rate, and the line of sight elevation angle. The specific control logic includes:

[0173] a. Expected value of the drone's yaw angle The control logic is as follows:

[0174] =

[0175] b. Expected value of the drone's pitch angle The control logic is as follows:

[0176] = , at this time the drone will lower its head and fly forward while also flying downward.

[0177] c. Expected vertical speed of the drone The control logic is as follows

[0178] It is the estimated value of the current missile-target line-of-sight elevation angle. is an estimate of the drone's horizontal velocity (scalar). is the expected value of the speed high and low angles in this control cycle. Then,

[0179]

[0180]

[0181] d. For the control of the desired value of the drone's roll angle, refer to the control logic of the second stage.

[0182] When the drone first enters "Vertical Speed ​​Control - Stage 3," the distance to the target is relatively large, so the line-of-sight angular rate is close to zero, precluding the need to switch to proportional guidance. As the distance to the target gradually decreases, the line-of-sight angular rate increases, allowing for proportional guidance. Therefore, when the line-of-sight angular rate exceeds the threshold, the drone enters "Vertical Speed ​​Control - Stage 4: Impact Control Based on the Proportional Guidance Algorithm."

[0183] In some embodiments, the control logic executed in the proportional guidance phase includes at least one of the following:

[0184] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0185] The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight.

[0186] The expected vertical speed of the UAV is obtained by multiplying the expected vertical speed angles of the previous control cycle by the proportional term of the proportional guidance algorithm in the vertical plane, the vertical speed of the missile-target sight line of sight, and the interval between two adjacent control cycles. The expected vertical speed is then determined by multiplying the tangent of the negative value of the expected vertical speed angles of the current control cycle by the estimated horizontal speed.

[0187] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0188] The principle of proportional guidance control is to perform guidance control based on the proportional relationship between the angular velocity of the UAV velocity vector and the line of sight angular rate. The parameters based on this control include the estimated horizontal velocity, the line of sight azimuth angular rate, and the line of sight pitch angular rate. The specific control logic includes:

[0189] a. Expected value of the drone's yaw angle The control logic is as follows:

[0190] =

[0191] b. Expected value of the drone's pitch angle The control logic is as follows:

[0192] = , at this time the drone will lower its head and fly forward while also flying downward.

[0193] c. Expected vertical speed of the drone The control logic is as follows:

[0194] is the expected value of the speed high and low angles in this control cycle, is the expected value of the speed high and low angles in the last control cycle, It is the proportional term of the proportional guidance method on the vertical plane. is the elevation and depression angular rate of the missile-target line of sight. dt is the interval between two adjacent control cycles, which is related to the frame rate of image processing.

[0195]

[0196] is the expected vertical velocity (velocity is positive when it is downward), is the estimated horizontal velocity of the UAV (scalar).

[0197] =

[0198] d. For the control of the desired roll angle of the drone, refer to the control logic of the second stage.

[0199] According to the above embodiments of the present application, during the process of the drone impacting the target, especially in the later stages, the drone's nose is always aligned or pointed at the target while completing the guidance. The benefits of this strict nose alignment include:

[0200] First, the target is unlikely to escape the camera's field of view, and the viewing angle is less affected by camera image distortion. Second, the target's image position remains unchanged when the drone's roll angle changes, which facilitates stable tracking for the image tracking algorithm. Third, it ensures that the drone's nose remains pointed toward the target during flight, facilitating the operation of directional payloads, such as fire sprinklers.

[0201] Combine Figure 4 As shown, the present application also protects a rotary wing UAV impact device 400, which includes:

[0202] a horizontal velocity estimation module 410 adapted to determine a total horizontal acceleration of the drone based on a tilt angle of the drone in each control cycle and a predetermined maximum horizontal velocity, and to determine a horizontal velocity estimate based on the total horizontal acceleration;

[0203] The sight angle determination module 420 is adapted to determine the sight angle of the missile and the target in the north-east coordinate system based on the parameters of the camera on the drone and the attitude of the drone, and to determine the sight angle according to the sight angle of the missile and the target and sight height angle;

[0204] The target impact control module 430 is adapted to control the impact of the target based on the horizontal velocity estimate, the line of sight azimuth, and the horizontal velocity estimate. Or at least one of the elevation angles of sight, the UAV is able to impact the target based on proportional guidance control and / or speed tracking.

[0205] Through the above embodiments, the UAV can achieve precise collision with the target in the absence of GPS signals.

[0206] In some embodiments, the horizontal velocity estimation module 410 is adapted to:

[0207] Determine the horizontal acceleration caused by the tilt of the drone based on the relationship between the acceleration of gravity and the tilt angle of the drone;

[0208] According to the functional relationship between the tilt angle and the maximum horizontal speed of the UAV determined in advance through testing, the maximum horizontal speed of the UAV in each control cycle is estimated;

[0209] Based on the relationship between the acceleration caused by air resistance and the current tilt angle, horizontal velocity, and maximum horizontal velocity of the UAV, the acceleration caused by air resistance is expressed as horizontal acceleration, and the total horizontal acceleration of the UAV is determined.

[0210] The estimated value of the horizontal velocity of the current control cycle is obtained by integrating the total horizontal acceleration and combining it with the horizontal velocity of the previous control cycle.

[0211] In some embodiments, the target impact control module 430 is adapted to:

[0212] Based on the control of the vertical speed of the UAV, the impact control of the UAV on the target is divided into multiple stages, including: the stage of yaw-turning the nose toward the target, the stage of running to the intersection point to control the elevation angle of the line of sight within the impact range of the target, the stage of speed tracking and guidance of the target, and / or the stage of proportional guidance.

[0213] In some embodiments, the control logic executed by the target impact control module 430 during the nose yaw steering phase includes at least one of the following:

[0214] The desired value of the yaw angle of the UAV is controlled to gradually approach the line of sight azimuth value, so that the UAV's nose turns towards the target direction;

[0215] The desired value of the pitch angle of the drone is controlled to gradually approach zero;

[0216] The expected vertical velocity of the drone is controlled to be zero;

[0217] The expected value of the roll angle of the drone is controlled to be zero.

[0218] In some embodiments, the control logic executed by the target impact control module 430 during the run-to-joint point phase to control the sight elevation angle within the impactable range of the target includes at least one of the following:

[0219] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0220] The control of the desired value of the pitch angle of the drone includes: if the sight elevation angle is greater than zero, and the height of the target is greater than the height of the drone, then the desired value of the pitch angle is controlled to tend toward or even be zero; if the sight elevation angle is less than a first threshold, then the desired value of the pitch angle is controlled to tend toward or even be zero; if the sight elevation angle is between zero and a second threshold, then the desired value of the pitch angle is controlled to tend toward or even be equal to the sight elevation angle, and the drone is controlled to fly upward simultaneously;

[0221] The control of the expected vertical speed of the UAV includes: multiplying the difference between the optimal trajectory angle and the current line of sight elevation angle by a proportional term to obtain the expected line of sight elevation rate, and adjusting the expected vertical speed so that the current line of sight elevation rate gradually approaches the expected line of sight elevation rate: when the expected line of sight elevation rate is greater than zero, controlling the expected vertical speed to make the UAV descend; when the expected line of sight elevation rate is less than zero, controlling the expected vertical speed to make the UAV climb.

[0222] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0223] In some embodiments, the control logic executed by the target impact control module 430 during the stage of performing velocity tracking guidance on the target includes at least one of the following:

[0224] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0225] The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight.

[0226] Controlling the expected vertical speed value of the UAV includes: determining the expected vertical speed value according to the product of the tangent value of the negative value of the sight elevation angle and the estimated horizontal speed value;

[0227] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0228] In some embodiments, the control logic executed in the proportional guidance phase of the target impact control module 430 includes at least one of the following:

[0229] Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target;

[0230] The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight.

[0231] The expected vertical speed of the UAV is obtained by multiplying the expected vertical speed angles of the previous control cycle by the proportional term of the proportional guidance algorithm in the vertical plane, the vertical speed of the missile-target sight line of sight, and the interval between two adjacent control cycles. The expected vertical speed is then determined by multiplying the tangent of the negative value of the expected vertical speed angles of the current control cycle by the estimated horizontal speed.

[0232] The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

[0233] It should be noted that the specific implementation of the above-mentioned device embodiments can refer to the specific implementation of the above-mentioned corresponding method embodiments, which will not be repeated here.

[0234] In summary, the embodiments of the present application achieve the following features or beneficial effects:

[0235] 1. A multi-rotor drone can achieve image-guided impact with a target in a GPS-free environment.

[0236] 2. Instead of relying on a pod, the vision-guided collision function can be achieved by simply mounting a low-cost strapdown camera horizontally on the drone.

[0237] 3. During image-guided flight, the drone's nose is always aligned with the target, and the target remains centered in the image. This has three advantages: First, the target is unlikely to leave the camera's field of view, and the viewing angle is less affected by camera image distortion. Second, the target's image position remains unchanged even when the drone's roll angle changes, which facilitates stable tracking for the image tracking algorithm. Third, it ensures that the drone's nose remains pointed toward the target throughout flight, facilitating the operation of directional payloads such as fire sprinklers.

[0238] It should be noted that:

[0239] The algorithms and displays provided herein are not inherently related to any particular computer, virtual device, or other device. Various general-purpose devices may also be used together with the teachings herein. Based on the above description, it is apparent that the structure required for constructing such devices is suitable. In addition, the present application is not directed to any specific programming language. It should be understood that various programming languages ​​may be utilized to implement the present application described herein, and the description of the specific languages ​​above is provided for the purpose of disclosing the preferred embodiment of the present application.

[0240] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures, and techniques are not shown in detail so as not to obscure the understanding of this description.

[0241] Similarly, it should be understood that in order to streamline the present application and facilitate understanding of one or more of the various aspects of the application, in the above description of exemplary embodiments of the present application, various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed application requires more features than are expressly recited in each claim.

[0242] Those skilled in the art will appreciate that the modules in the devices of the embodiments can be adaptively modified and installed in one or more devices different from the embodiments. The modules, units, or components in the embodiments can be combined into a single module, unit, or component, and furthermore, they can be divided into multiple sub-modules, sub-units, or sub-components. All features disclosed in this specification (including the accompanying claims, abstract, and drawings), and all processes or units of any method or device disclosed therein, can be combined in any combination, unless at least some of such features and / or processes or units are mutually exclusive. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0243] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features and not other features included in other embodiments, the combination of features from different embodiments is meant to be within the scope of this application and to form different embodiments.

[0244] The various component embodiments of the present application can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will appreciate that, in practice, a microprocessor or digital signal processor (DSP) can be used to implement some or all of the functions of some or all of the components of the rotary-wing drone impact device according to the embodiments of the present application. The present application can also be implemented as an apparatus or device program (e.g., a computer program or computer program product) for performing part or all of the methods described herein. Such a program implementing the present application can be stored on a computer-readable medium or in the form of one or more signals. Such signals can be downloaded from an internet website, provided on a carrier signal, or provided in any other form.

[0245] An embodiment of the present application provides a non-volatile computer storage medium, which stores at least one executable instruction. The computer executable instruction can execute the above-mentioned rotorcraft UAV impact method in any of the above-mentioned method embodiments.

[0246] Figure 5 A schematic structural diagram of an embodiment of a UAV (flight control system) of the present application is shown. The specific embodiments of the present application do not limit the specific structure of the UAV.

[0247] like Figure 5 As shown, the flight control system of the UAV may include: a processor 502 , a communications interface 504 , a memory 506 , and a communication bus 508 .

[0248] Processor 502, communication interface 504, and memory 506 communicate with each other via communication bus 508. Communication interface 504 is used to communicate with other devices, such as client devices or other server network elements. Processor 502 is used to execute program 510, which may specifically perform the steps described in the embodiment of the rotorcraft drone impact method for a drone.

[0249] Specifically, the program 510 may include program codes, which include computer operation instructions.

[0250] Processor 502 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. The one or more processors included in the drone may be processors of the same type, such as one or more CPUs, or processors of different types, such as one or more CPUs and one or more ASICs.

[0251] The memory 506 is used to store the program 510. The memory 506 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage.

[0252] Program 510 can be specifically used to enable processor 502 to perform operations corresponding to the above-mentioned rotorcraft drone impact method embodiment.

[0253] It should be noted that the above embodiments illustrate rather than limit the present application, and that a person skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbols placed between brackets should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present application may be implemented by means of hardware comprising several different elements and by means of appropriately programmed computers. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names.

Claims

1. A rotorcraft UAV impact method for impacting a target using the flight control system of the UAV in the absence of GPS signals, characterized in that: The method comprises: determining a total horizontal acceleration of the UAV based on a tilt angle of the UAV in each control cycle and a predetermined maximum horizontal velocity, and determining a horizontal velocity estimate based on the total horizontal acceleration; Based on the parameters of the camera on the UAV and the attitude of the UAV, the unit vector of the missile-target line of sight in the north-east coordinate system is determined, and the azimuth and elevation angle of the line of sight are determined based on the unit vector of the missile-target line of sight. Based on at least one of the horizontal velocity estimate, the line of sight azimuth, or the line of sight elevation angle, the UAV is caused to impact the target using proportional guidance control and velocity tracking control; The total horizontal acceleration of the UAV is determined based on the tilt angle of the UAV in each control cycle and a predetermined maximum horizontal velocity. The horizontal velocity estimation value is determined based on the total horizontal acceleration, including: Determine the horizontal acceleration caused by the tilt of the drone based on the relationship between the acceleration of gravity and the tilt angle of the drone; According to the functional relationship between the tilt angle and the maximum horizontal speed of the UAV determined in advance through testing, the maximum horizontal speed of the UAV in each control cycle is estimated; Based on the relationship between the acceleration caused by air resistance and the current tilt angle, horizontal velocity, and maximum horizontal velocity of the UAV, the acceleration caused by air resistance is expressed as horizontal acceleration, and the total horizontal acceleration of the UAV is determined. The estimated value of the horizontal velocity of the current control cycle is obtained by integrating the total horizontal acceleration and combining it with the horizontal velocity of the previous control cycle.

2. The method according to claim 1, characterized in that Based on at least one of a horizontal velocity estimate, a line of sight azimuth, or a line of sight elevation angle, achieving collision of the UAV with the target using proportional guidance control and velocity tracking control includes: Based on the control of the vertical speed of the UAV, the impact control of the UAV on the target is divided into multiple stages, including: the stage of yaw-turning the nose toward the target, the stage of running to the intersection point with the elevation angle of the line of sight controlled within the impactable range of the target, the stage of speed tracking and guiding the target, and the stage of proportional guidance.

3. The method according to claim 2, characterized in that The control logic executed during the nose yaw steering phase includes at least one of the following: The desired value of the yaw angle of the UAV is controlled to gradually approach the line of sight azimuth value, so that the UAV's nose turns towards the target direction; The desired value of the pitch angle of the drone is controlled to gradually approach zero; The expected vertical velocity of the drone is controlled to be zero; The expected value of the roll angle of the drone is controlled to be zero.

4. The method according to claim 2, characterized in that The control logic executed during the run-to-joint point phase to control the sight elevation angle within the target's impact range includes at least one of the following: Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target; The control of the desired value of the pitch angle of the drone includes: if the sight elevation angle is greater than zero, and the height of the target is greater than the height of the drone, then the desired value of the pitch angle is controlled to tend toward or even be zero; if the sight elevation angle is less than a first threshold, then the desired value of the pitch angle is controlled to tend toward or even be zero; if the sight elevation angle is between zero and a second threshold, then the desired value of the pitch angle is controlled to tend toward or even be equal to the sight elevation angle, and the drone is controlled to fly forward and upward at the same time; The control of the expected vertical speed of the UAV includes: multiplying the difference between the optimal trajectory angle and the current line of sight elevation angle by a proportional term to obtain the expected line of sight elevation rate, and adjusting the expected vertical speed so that the current line of sight elevation rate gradually approaches the expected line of sight elevation rate: when the expected line of sight elevation rate is greater than zero, controlling the expected vertical speed to make the UAV descend; when the expected line of sight elevation rate is less than zero, controlling the expected vertical speed to make the UAV climb. Controlling the expected roll angle of the UAV includes: determining the expected horizontal lateral acceleration based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle and the acceleration of gravity; and determining the expected roll angle based on the arc tangent of the quotient of the expected horizontal lateral acceleration and the expected vertical acceleration. The optimal trajectory angle is the average of the first and second thresholds of the sight line elevation angle.

5. The method according to claim 2, characterized in that The control logic executed during the stage of speed tracking and guiding the target includes at least one of the following: Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target; The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight. Controlling the expected vertical speed value of the UAV includes: determining the expected vertical speed value according to the product of the tangent value of the negative value of the sight elevation angle and the estimated horizontal speed value; The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

6. The method according to claim 2, characterized in that The control logic executed in the proportional guidance phase includes at least one of the following: Control the desired yaw angle of the drone to be equal to the line of sight azimuth angle, keeping the drone's nose facing the target; The desired pitch angle of the drone is controlled to be equal to the elevation angle of sight. The expected vertical speed of the UAV is obtained by multiplying the expected vertical speed angles of the previous control cycle by the proportional term of the proportional guidance algorithm in the vertical plane, the vertical speed of the missile-target sight line of sight, and the interval between two adjacent control cycles. The expected vertical speed is then determined by multiplying the tangent of the negative value of the expected vertical speed angles of the current control cycle by the estimated horizontal speed. The expected roll angle value of the UAV is controlled by: determining the expected horizontal lateral acceleration value based on the product of the line of sight azimuth rate, the proportional term of the proportional guidance algorithm in the horizontal plane, and the estimated value of the horizontal velocity; determining the vertical acceleration value that meets the expectation of straight-line flight based on the expected pitch angle value and the acceleration of gravity; and determining the expected roll angle value based on the arc tangent of the quotient of the expected horizontal lateral acceleration value and the expected vertical acceleration value.

7. A rotor UAV impact device for impacting a target using the flight control system on the UAV in the absence of GPS signals, characterized in that: The device comprises: a horizontal velocity estimation module adapted to determine a total horizontal acceleration of the UAV based on a tilt angle of the UAV in each control cycle and a predetermined maximum horizontal velocity, and to determine a horizontal velocity estimation value based on the total horizontal acceleration; The sight angle determination module is suitable for determining the missile-target sight unit vector in the north-east coordinate system based on the parameters of the drone's camera and the drone's attitude, and determining the sight azimuth and sight altitude angle based on the missile-target sight unit vector; a target impact control module adapted to achieve the impact of the UAV on the target according to proportional guidance control and speed tracking control based on at least one of the horizontal velocity estimate, the line of sight azimuth angle, or the line of sight elevation angle; The horizontal velocity estimation module is specifically suitable for: Determine the horizontal acceleration caused by the tilt of the drone based on the relationship between the acceleration of gravity and the tilt angle of the drone; According to the functional relationship between the tilt angle and the maximum horizontal speed of the UAV determined in advance through testing, the maximum horizontal speed of the UAV in each control cycle is estimated; Based on the relationship between the acceleration caused by air resistance and the current tilt angle, horizontal velocity, and maximum horizontal velocity of the UAV, the acceleration caused by air resistance is expressed as horizontal acceleration, and the total horizontal acceleration of the UAV is determined. The estimated value of the horizontal velocity of the current control cycle is obtained by integrating the total horizontal acceleration and combining it with the horizontal velocity of the previous control cycle.

8. A drone, characterized in that: The invention comprises a processor and a memory arranged to store computer-executable instructions, wherein when the instructions are executed, the processor is caused to perform the rotorcraft UAV impact method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores one or more programs, and when the one or more programs are executed by a processor, the rotorcraft UAV impact method according to any one of claims 1 to 6 is implemented.

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