A fully-driven tilt-rotor integrated flying gun model and backstepping control method

Abstract

The present invention provides a fully-driven tilt-rotor integrated flying gun model and a backstepping control method, aiming to solve the problem that the existing under-driven integrated flying gun cannot hover and shoot with a pitch angle and the fire control strategy is complicated during the mobile shooting process, as well as the problem that the control allocation method of the over-driven unmanned aerial vehicle is complicated. The present invention includes the following steps: each of the four rotors adds two tilting degrees of freedom, establishes the wing, body, and earth coordinate system, and establishes the conversion relationship; constructs a dynamic model of the linear motion and angular motion of the fully-driven tilt-rotor integrated flying gun; designs a backstepping controller based on the model, clarifies the virtual control output; and establishes a mapping relationship from the virtual control output to the output of the actuator. The present invention provides a design scheme for a fully-driven tilt-rotor integrated flying gun, which realizes the decoupling control of displacement and attitude, can complete the hovering shooting and follow-up shooting of the check-and-shoot function, can effectively simplify the control allocation method, and meet the technical requirements of fast and accurate shooting of weapons.

Description

Technical Field

[0001] The invention belongs to the technical field of weapon control, and in particular relates to a full-drive tilt-rotor integrated flying gun model and a backstepping control method. Background Art

[0002] Drones are highly concealed, highly maneuverable, and relatively inexpensive. They have performed well in reconnaissance, interception, and attack, and have gradually become a key area of ​​development for various countries. Flying guns refer to gun-type armed drones, which are mainly divided into two structures: machine / gun integrated and machine / gun independent. The machine / gun integrated flying gun has a simple structure, is easy to carry, and is easy to disassemble, which has unique advantages.

[0003] At present, integrated flying guns usually use ordinary quadcopters as carriers, which are under-actuated systems with strong coupling between position control and attitude control. When the flying gun adjusts the gun line, that is, adjusts the attitude of the flying gun, it will inevitably cause the body to move, and it is impossible to achieve hovering shooting with a pitch angle; in addition, for mobile shooting, it is necessary to obtain the flight trajectory through complex control strategies such as flight / fire control couplers, and the shooting response speed is slow and the shooting accuracy is low. Although conventional tilt-rotor drones can achieve the decoupling of displacement and attitude, they are mostly over-actuated systems, and the control allocation strategy is relatively complex. Summary of the invention

[0004] The purpose of the present invention is to provide a fully driven tilt-rotor integrated flying gun model and a backstepping control method, which are used to solve the technical problems of ordinary four-rotor flying gun displacement attitude coupling and the complex tilt-rotor flying gun control allocation strategy in the prior art.

[0005] The present application provides a backstepping control method for a fully-driven tilt-rotor integrated flying gun model, the method comprising:

[0006] Step 1: Each quadrotor adds two tilting degrees of freedom, and controls the rotor to tilt in pitch and roll respectively. The tilt angles of the same degree of freedom of different rotors are the same. The wing, body, and earth coordinate systems are established to establish the conversion relationship.

[0007] Step 2, constructing a dynamic model of the linear motion and angular motion of the all-drive tilt-rotor integrated flying gun;

[0008] Step 3, designing a backstepping controller based on the dynamics model of the linear motion and angular motion of the all-drive tiltrotor integrated flying gun, and clarifying the virtual control output; the virtual control output includes lift and virtual control torque;

[0009] Step 4, establishing a mapping relationship from the virtual control output to the actuator output; wherein the actuator output includes the rotor tilt angle and the rotor speed.

[0010] Furthermore, each quadrotor adds two tilting degrees of freedom to control the rotor to tilt in pitch and roll respectively. The tilt angles of the same degree of freedom of different rotors are the same. The wing, fuselage, and earth coordinate systems are established, and the conversion relationship is established, including:

[0011] Establish the following coordinate system: Wing coordinate system C wi :{O wi ;X wi ; Y wi ; Z wi}i=1,2,3,4, body coordinate system C b :{O b ;X b ; Y b ; Z b} and the geodetic coordinate system C e :{O e ;X e ; Y e ; Z e}, in the initial state, the body coordinate system and the earth coordinate system coincide;

[0012] set up R y θ、R z ψ represents the rotation of the right-hand coordinate system around the x, y, and z axes respectively The rotation matrix of θ and ψ degrees is defined as counterclockwise.

[0013] From the body coordinate system C b Rotate to the geodetic coordinate system C e The parallel rotation matrix is:

[0014]

[0015] In the above formula is the gun roll angle, θ is the gun pitch angle, ψ is the gun yaw angle, s· represents sin·, c· represents cos·, and · refers to any angle;

[0016] Regulation R x β, R y α represents the rotation matrix of the right-hand coordinate system rotating around the x and y axes by β and α degrees respectively; if the four rotors simultaneously produce α degrees of pitch tilt and β degrees of roll tilt, then the wing coordinate system C wi Rotate to the body coordinate system C b The parallel rotation matrix is:

[0017]

[0018] Further, step 2, constructing a dynamic model of linear motion and angular motion of a fully-driven tilt-rotor integrated flying gun, including:

[0019] Step 2-1: The lift generated by the rotor rotation is related to O in the rotor coordinate system. wi Z wi The axis direction is consistent, perpendicular to the rotor surface and facing outward; if the four rotors simultaneously produce α degrees of pitch tilt and β degrees of roll tilt, the total lift effect on the gun in the body coordinate system is:

[0020]

[0021] In the formula, F Tx 、F Ty 、F Tz They are the total lift F in the body coordinate system T The components on the x, y, and z axes, T i =[00C T w i 2 ], i = 1, 2, 3, 4, are the lift in the four rotor coordinate systems, C T is the lift coefficient, w i is the rotation speed of each rotor.

[0022] The total lift F in the body coordinate system T Converted to the geodetic coordinate system, according to the total lift and gravity in the body coordinate system, the resultant force on the flying gun in the geodetic coordinate system is:

[0023]

[0024] In the formula F e is the total lift in the geodetic coordinate system, m is the mass of the gun, and g is the local gravitational acceleration;

[0025] Step 2-2, the lift generated by the rotation of the rotor generates a torque relative to the center of the fuselage. After the lift is converted to the fuselage coordinate system, the torque generated by the lift in the fuselage coordinate system is as follows:

[0026]

[0027] Where M tx 、M ty 、M tz It is M t Components on the x, y, and z axes, the lever arm They are:

[0028]

[0029] d x Indicates the Y coordinate system from the rotor center to the fuselage b Axis distance, d y Indicates the coordinate system X from the rotor center to the fuselageb The distance between the axes;

[0030] Step 2-3, the anti-torque moment generated by the rotor rotation is as follows in the body coordinate system:

[0031]

[0032] Where M qx 、M qy 、M qz It is M q The components on the x, y, and z axes, They are the anti-torque moments in the four rotor coordinate systems, C M is the anti-torque coefficient;

[0033] Step 2-4, the gyroscopic torque generated by the high-speed rotation of the rotor is as follows in the body coordinate system:

[0034]

[0035] Where M gx 、M gy 、M gz It is M g Components on the x, y, and z axes, Ω = [pqr] T is the angular velocity of the gun body, J p It is the sum of the moments of inertia of the motor rotor and the rotor;

[0036] Step 2-5, according to the Newton-Euler equation:

[0037]

[0038] Among them, M k =[M kx M ky M kz ] T =[qr(J z -J y ) pr(J x -J z ) pq(J y -J x )] T is the Coriolis centripetal moment, M kx 、M ky 、M kz It is M k The components on the x, y, and z axes, N = diag([mmm J x J y J z ]) is the inertia matrix, J x , J y , Jz is the moment of inertia of the flying gun rotating around three axes, is the flying gun linear velocity;

[0039] In the case of small disturbance, the attitude angle change is small, and the attitude angular velocity of the flying gun is equal to the angular velocity of the body, that is, Therefore, the model of the flying gun in the geodetic coordinate system is as follows:

[0040]

[0041] in

[0042] Further, in step 3, a backstepping controller is designed based on the dynamic model of the linear motion and angular motion of the all-drive tiltrotor integrated flying gun, and the virtual control output is clarified, including:

[0043] Step 3-1, establish the nonlinear state space expression of the flying gun:

[0044]

[0045] In the formula That is, the displacement and attitude state variables of the flying gun, f2(x1,x2)=N -1 [00-mg (M g -M k ) T ] T , u=[F ex F ey F ez M x M y M z ] T =[F e T (M t +M q ) T ] T , represents the lift and virtual control torque on the flying gun on the x, y, and z axes, B = N -1 ;

[0046] Step 3-2, design a backstepping controller and calculate the virtual control output; the virtual control output includes lift and virtual control torque;

[0047] Define the error function as e1=x1-x d , x d is the expected position and posture of the flying gun, e2=x2-α, α is the virtual control quantity and the positive definite Lyapunov function is but

[0048] Pick K1 is a sixth-order positive diagonal matrix, then

[0049] Pick but

[0050] Pick Where K2 is a sixth-order positive diagonal matrix, then The back-stepping controller makes the flying gun system gradually stable.

[0051] According to the backstepping controller, the virtual control torque M is obtained x 、M y 、M z and the lift F in the geodetic coordinate system ex 、F ey 、F ez , convert the lift force to the body coordinate system, the lift force in the body coordinate system is:

[0052]

[0053] The total lift force on the flying gun is obtained by synthesizing the components on the x, y, and z axes:

[0054]

[0055] Furthermore, step 4 needs to establish a mapping relationship between the virtual control output and the actuator output, including:

[0056] Control position and posture separately;

[0057] Step 4-1, the lift components of the x, y, and z axes can be obtained by the backstepping controller to determine the rotor tilt angle:

[0058]

[0059] Step 4-2: The virtual control torque can be obtained by the backstepping controller. Combined with the flying gun dynamics model, the mapping relationship between the virtual control output and the rotor speed is as follows:

[0060]

[0061] in

[0062] The rotor speed distribution is as follows:

[0063]

[0064] The present application also provides a fully-driven tilt-rotor integrated flying gun model, which is established according to the method provided in the present application, and the model includes:

[0065] The model of the flying gun in the geodetic coordinate system is as follows:

[0066]

[0067] in w i , i = 1, 2, 3, 4 is the rotation speed of the four rotors of the flying gun, C T is the lift coefficient; d x The Y coordinate system from the rotor center to the fuselage b Axis distance, d y Indicates the coordinate system X from the rotor center to the fuselage b Axis distance, C M is the anti-torque coefficient; s· represents sin·, c· represents cos·, · refers to any angle, x, y, z are the displacements of the flying gun along the x, y, z axes, θ, ψ are the roll angle, pitch angle, and yaw angle of the gun, α, β are the pitch angle and roll angle of the gun rotor; m is the mass of the gun, g is the local gravity acceleration; p, q, r are the angular velocities of the gun body; J x , J y , J z is the moment of inertia of the flying gun rotating around three axes; M gx 、M gy 、M gz is the gyroscopic moment M g Components on the x, y, and z axes; M kx 、M ky 、M kz is the Coriolis centripetal moment M k Components on the x, y, and z axes.

[0068] Compared with the prior art, the present invention has the following significant advantages: 1. The model of the present invention can realize decoupling control of displacement and attitude, realize hovering shooting with pitch angle that cannot be achieved by ordinary four-rotor integrated flying guns, and simplify the fire control method of tracking shooting; 2. The model of the present invention realizes a full-drive system with six inputs and six outputs, simplifies the control distribution scheme, and can accurately track attitude and displacement with high tracking accuracy.

[0069] The present invention will be described in further detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 This is a schematic diagram of the structure of the tilt-rotor integrated flying gun described in the present invention.

[0071] Figure 2 Schematic diagram of the control distribution scheme of the present invention.

[0072] Figure 3 This is a three-dimensional graph of trajectory tracking in an embodiment of the present invention.

[0073] Figure 4 It is a top view of trajectory tracking in an embodiment of the present invention.

[0074] Figure 5 This is an x-direction tracking diagram of hovering shooting in an embodiment of the present invention.

[0075] Figure 6 This is a Y-direction tracking diagram of hovering shooting in an embodiment of the present invention.

[0076] Figure 7 This is a z-direction tracking diagram for hovering shooting in an embodiment of the present invention.

[0077] Figure 8 This is a hover shooting pitch angle tracking diagram in an embodiment of the present invention.

[0078] Fig. 9 This is a hover shooting roll angle tracking diagram in an embodiment of the present invention.

[0079] Fig.10 This is a yaw angle tracking diagram for hovering shooting in an embodiment of the present invention.

[0080] Fig.11 This is the x-direction tracking diagram for tracking shooting in an embodiment of the present invention.

[0081] Fig.12 The Y-direction tracking diagram of the tracking shooting in the embodiment of the present invention is

[0082] Fig.13 This is a z-direction tracking diagram for tracking shooting in an embodiment of the present invention.

[0083] Fig.14 This is a tracking diagram of the pitch angle of tracking shooting in an embodiment of the present invention.

[0084] Fig.15 This is a rolling angle tracking diagram for tracking shooting in an embodiment of the present invention.

[0085] Fig.16 This is a yaw angle tracking diagram for tracking shooting in an embodiment of the present invention. DETAILED DESCRIPTION

[0086] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with 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 intended to limit the present invention.

[0087] Combination Figure 1 The present invention relates to a fully-driven tilt-rotor integrated flying gun model, which adopts an integrated machine / gun "H" type layout, wherein the gun body is the machine body, and the bAxis distribution, rotors 1 and 3 are diagonally distributed and rotate clockwise, and rotors 2 and 4 are diagonally distributed and rotate counterclockwise. The present invention adds two tilting degrees of freedom at each rotor of the flying gun, and controls the rotor of the flying gun to tilt in pitch and roll directions respectively (the tilt angle in pitch direction is α degrees, and the tilt angle in roll direction is β degrees), wherein the tilt angles of the same degree of freedom of different rotors are the same. The above method can be used to simplify the tilt-rotor integrated flying gun into a full-drive system with six inputs and six outputs, wherein the six inputs refer to the pitch direction, the roll direction tilt angle and the four rotor speeds, and the six outputs refer to the position and attitude of the flying gun, thereby realizing the decoupling control of the position and attitude of the UAV, and simplifying the control distribution method. The following steps are included:

[0088] Step 1: Each quadrotor adds two tilting degrees of freedom, and controls the rotor to tilt in pitch and roll respectively. The tilt angles of the same degree of freedom of different rotors are the same. The wing, body, and earth coordinate systems are established to establish the conversion relationship.

[0089] Step 2, constructing a dynamic model of the linear motion and angular motion of the all-drive tilt-rotor integrated flying gun;

[0090] Step 3, designing a backstepping controller based on the dynamics model of the linear motion and angular motion of the all-drive tiltrotor integrated flying gun, and clarifying the virtual control output; the virtual control output includes lift and virtual control torque;

[0091] Step 4, establishing a mapping relationship from the virtual control output to the actuator output; wherein the actuator output includes the rotor tilt angle and the rotor speed.

[0092] Furthermore, the coordinate system and the relationship between coordinate systems in step 1 specifically include:

[0093] Combination Figure 1 The coordinate system involved in the present invention mainly includes the wing coordinate system C wi :{O wi ;X wi ; Y wi ; Z wi}(i=1,2,3,4), body coordinate system C b :{O b ;X b ; Y b ; Z b} and the geodetic coordinate system C e :{O e ;X e ; Y e ; Z e}, in the initial state, the body coordinate system and the earth coordinate system coincide. R y θ、R z ψ represents the rotation of the right-hand coordinate system around the x, y, and z axes respectively The rotation matrix of θ and ψ degrees is defined as counterclockwise.

[0094] From the body coordinate system C b Rotate to the geodetic coordinate system C e The parallel rotation matrix is:

[0095]

[0096] In the above formula is the rolling angle of the flying gun, θ is the pitch angle of the flying gun, and ψ is the yaw angle of the flying gun. In addition, in the present invention, s· represents sin·, c· represents cos·, and · refers to any angle.

[0097] Regulation R x β, R y α represents the rotation matrix of the right-hand coordinate system rotating around the x and y axes by β and α degrees respectively; if the four rotors simultaneously produce α degrees of pitch tilt and β degrees of roll tilt, then the wing coordinate system C wi Rotate to the body coordinate system C b The parallel rotation matrix is:

[0098]

[0099] Step 2, construct the dynamic model of the linear motion and angular motion of the all-drive tilt-rotor integrated flying gun, including:

[0100] Step 2-1: The lift generated by the rotor rotation is related to O in the rotor coordinate system. wi Z wi The axis direction is consistent, perpendicular to the rotor surface and facing outward; if the four rotors simultaneously produce α degrees of pitch tilt and β degrees of roll tilt, the total lift effect on the gun in the body coordinate system is:

[0101]

[0102] In the formula, F Tx 、F Ty 、F Tz They are the total lift F in the body coordinate system T The components on the x, y, and z axes, T i =[0 0C T w i 2 ], i = 1, 2, 3, 4, are the lift in the four rotor coordinate systems, C T is the lift coefficient, w i is the rotation speed of each rotor.

[0103] The total lift F in the body coordinate system TConverted to the geodetic coordinate system, according to the total lift and gravity in the body coordinate system, the resultant force on the flying gun in the geodetic coordinate system is:

[0104]

[0105] In the formula is the total lift in the geodetic coordinate system, m is the mass of the gun, and g is the local gravitational acceleration;

[0106] Step 2-2, the lift generated by the rotation of the rotor generates a torque relative to the center of the fuselage. After the lift is converted to the fuselage coordinate system, the torque generated by the lift in the fuselage coordinate system is as follows:

[0107]

[0108] Where M tx 、M ty 、M tz It is M t Components on the x, y, and z axes, the lever arm O w b i They are:

[0109]

[0110] d x Indicates the Y coordinate system from the rotor center to the fuselage b Axis distance, d y Indicates the coordinate system X from the rotor center to the fuselage b The distance between the axes;

[0111] Step 2-3, the anti-torque moment generated by the rotor rotation is as follows in the body coordinate system:

[0112]

[0113] Where M qx 、M qy 、M qz It is M q The components on the x, y, and z axes, They are the anti-torque moments in the four rotor coordinate systems, C M is the anti-torque coefficient;

[0114] Step 2-4, the gyroscopic torque generated by the high-speed rotation of the rotor is as follows in the body coordinate system:

[0115]

[0116] Where M gx 、M gy 、M gz It is M gComponents on the x, y, and z axes, Ω = [pqr] T is the angular velocity of the gun body, J p It is the sum of the moments of inertia of the motor rotor and the rotor;

[0117] Step 2-5, according to the Newton-Euler equation:

[0118]

[0119] Among them, M k =[M kx M ky M kz ] T =[qr(J z -J y ) pr(J x -J z ) pq(J y -J x )] T is the Coriolis and centripetal force matrix, M kx 、M ky 、M kz It is M k The components on the x, y, and z axes, N = diag([mmm J x J y J z ]) is the inertia matrix, J x , J y , J z is the moment of inertia of the flying gun rotating around three axes, is the flying gun linear velocity;

[0120] In the case of small disturbance, the attitude angle change is small, and the attitude angular velocity of the flying gun is equal to the angular velocity of the body, that is, Therefore, the model of the flying gun in the geodetic coordinate system is as follows:

[0121]

[0122] in

[0123] Step 3: Design a backstepping controller based on the dynamic model of the linear motion and angular motion of the all-drive tiltrotor integrated flying gun, and clarify the virtual control output, including:

[0124] Step 3-1, establish the nonlinear state space expression of the flying gun:

[0125]

[0126] In the formula That is, the displacement and attitude state variables of the flying gun, f2(x1,x2)=N -1 [00-mg (M g -M k ) T ] T , u=[F ex F ey F ez M x M y M z ] T =[F e T (M t +M q ) T ] T , represents the lift and virtual control torque on the flying gun on the x, y, and z axes, B = N -1 ;

[0127] Step 3-2, design a backstepping controller and calculate the virtual control output; the virtual control output includes lift and virtual control torque;

[0128] Define the error function as e1=x1-x d , x d is the expected position and posture of the flying gun, e2=x2-α, α is the virtual control quantity, which is obtained during the design process; the positive Lyapunov function is taken as but

[0129] Pick K1 is a sixth-order positive diagonal matrix, then

[0130] Pick but

[0131] Pick Where K2 is a sixth-order positive diagonal matrix, then The back-stepping controller makes the flying gun system gradually stable.

[0132] According to the backstepping controller, the virtual control torque M is obtained x 、M y 、M z and the lift F in the geodetic coordinate system ex 、F ey 、F ez , convert the lift force to the body coordinate system, the lift force in the body coordinate system is:

[0133]

[0134] The total lift force on the flying gun is obtained by synthesizing the components on the x, y, and z axes:

[0135]

[0136] Step 4 requires establishing a mapping relationship from the virtual control output to the actuator output.

[0137] Since the position and attitude are decoupled, the position and attitude can be controlled separately;

[0138] From the dynamic model, it can be seen that when the speeds of the four rotors are the same, no control torque will be generated, so the attitude angle of the gun will not change. Position control can be achieved by controlling the rotor tilt angle and the total lift of the gun. On this basis, the speeds of the four rotors can be further distributed to achieve attitude decoupling control, and the control idea is clear. Compared with the conventional overdriven tilt-rotor UAV system, the difficulty of control distribution is reduced. Its overall control distribution scheme is as follows: Figure 2 Specifically including:

[0139] Step 4-1, the lift components of the x, y, and z axes can be obtained by the backstepping controller to determine the rotor tilt angle:

[0140]

[0141] Step 4-2: The virtual control torque can be obtained by the backstepping controller. Combined with the flying gun dynamics model, the mapping relationship between the virtual control output and the rotor speed is as follows:

[0142]

[0143] in

[0144] The rotor speed distribution is as follows:

[0145]

[0146] The present application also provides a fully-driven tilt-rotor integrated flying gun model, which is established according to the method provided in the present application. The model of the flying gun in the geodetic coordinate system is as follows:

[0147]

[0148] in w i , i = 1, 2, 3, 4 is the rotation speed of the four rotors of the flying gun, C T is the lift coefficient; d x The Y coordinate system from the rotor center to the fuselage b Axis distance, d y Indicates the coordinate system X from the rotor center to the fuselageb Axis distance, C M is the anti-torque coefficient; s· represents sin·, c· represents cos·, · refers to any angle, x, y, z are the displacements of the flying gun along the x, y, z axes, θ, ψ are the roll angle, pitch angle, and yaw angle of the gun, α, β are the pitch angle and roll angle of the gun rotor; m is the mass of the gun, g is the local gravity acceleration; p, q, r are the angular velocities of the gun body; J x , J y , J z is the moment of inertia of the flying gun rotating around three axes; M gx 、M gy 、M gz is the gyroscopic moment M g Components on the x, y, and z axes; M kx 、M ky 、M kz is the Coriolis centripetal moment M k The components on the x, y, and z axes. The establishment process method can be found in the method provided in this application, which will not be repeated here.

[0149] The present application is further described below in conjunction with specific embodiments.

[0150] This example focuses on simulating the actual shooting process of the flying gun, and does not consider the impact vibration and wind disturbance that may be generated when the flying gun is shooting. The focus is on studying the performance of the flying gun in different shooting scenarios. The flying gun needs to be able to reliably track the expected displacement and attitude, be able to achieve hovering shooting with pitch angles, and be able to maintain a fixed attitude angle during tracking shooting.

[0151] This embodiment assumes that the flying gun performs climbing motion, translational motion along the x-axis and y-axis, three-dimensional motion, and gyroscopic ascending motion in sequence. Figure 3 and Figure 4 As shown in the figure, the flying guns accurately tracked the set flight trajectory, and there was only a certain adjustment stage when the trajectory suddenly changed. After calculation, the average tracking errors in the x, y, and z directions were 3.13cm, 3.76cm, and 0.25cm, respectively.

[0152] Simulate the hovering shooting of the flying gun, that is, the "static-moving" shooting mode. Within 0-5 seconds, the simulated shooting target moves in front of the flying gun, and the flying gun constantly adjusts its pitch angle to shoot; within 5-10 seconds, the simulated shooting target makes uniform circular motion around the flying gun, and the flying gun maintains a certain pitch angle and then makes uniform motion at the yaw angle. During the shooting process, the changes in position and posture are as follows: Figure 5-Figure 10As shown in the figure, in the process of adjusting the pitch angle and yaw angle, the changes in position and roll angle are extremely small and can be ignored, which proves that the model has achieved the decoupling of position and attitude. At the same time, the attitude angle accurately tracks the set target value. The average tracking errors of the pitch angle and yaw angle are calculated to be 0.033mrad and 0.117mrad respectively, which meet the requirements of hovering shooting.

[0153] Simulate the tracking shooting of the flying gun, that is, the "moving-moving" shooting mode. Within 0-10s, maintain a fixed pitch angle and yaw angle, and the flying gun moves at a constant speed along the x and y axes respectively. During the position change, the posture remains unchanged. Simulate the most common situation of tracking shooting within 10-20s. During the movement, the flying gun continuously adjusts its pitch angle and yaw angle according to the target information captured by the optoelectronics, which tests the comprehensive tracking ability of the flying gun. According to Figure 11-16 The position and posture can be accurately tracked. Although the roll angle will produce small fluctuations, it will not affect the shooting accuracy.

[0154] The present invention designs a fully-driven tilt-rotor aircraft / gun integrated flying gun, which solves the coupling problem of position and attitude of ordinary four-rotor flying guns, and can realize hovering shooting with pitch angles that ordinary four-rotor integrated flying guns cannot do, greatly reducing the control difficulty of fire control during the mobile shooting process of the flying gun. At the same time, by controlling the tilt angle of the rotor in two dimensions, the tilt-rotor UAV is simplified from an eight-input six-output overdrive system to a six-input six-output full-drive system, simplifying the control allocation strategy, and is suitable for flight / fire control systems with high real-time requirements. The flying gun model can accurately track the set trajectory and set attitude, and the displacement and attitude are decoupled, which can meet the shooting requirements of the flying gun including hovering shooting, mobile shooting, etc.

Claims

1. A backstepping control method for a fully-driven tiltrotor integrated flying gun model. It is characterized in that The method comprises: Step 1: Each quadrotor adds two tilting degrees of freedom, and controls the rotor to tilt in pitch and roll respectively. The tilt angles of the same degree of freedom of different rotors are the same. The wing, body, and earth coordinate systems are established to establish the conversion relationship. Step 2, constructing a dynamic model of the linear motion and angular motion of the all-drive tilt-rotor integrated flying gun; Step 3, designing a backstepping controller based on the dynamics model of the linear motion and angular motion of the all-drive tiltrotor integrated flying gun, and clarifying the virtual control output; the virtual control output includes lift and virtual control torque; Step 4, establishing a mapping relationship between the virtual control output and the actuator output; wherein the actuator output includes the rotor tilt angle and the rotor speed; Each quadrotor adds two tilting degrees of freedom to control the rotor to tilt in pitch and roll respectively. The tilt angles of the same degree of freedom of different rotors are the same. The wing, fuselage, and earth coordinate systems are established, and the conversion relationship is established, including: Establish the following coordinate system: Wing coordinate system C wi :{O wi ;X wi ; Y wi ; Z wi }i=1,2,3,4, body coordinate system C b :{O b ;X b ; Y b ; Z b } and the geodetic coordinate system C e :{O e ;X e ; Y e ; Z e }, in the initial state, the body coordinate system and the earth coordinate system coincide; set up R y θ、R z ψ represents the rotation of the right-handed coordinate system around the x, y, and z axes respectively The rotation matrix of θ and ψ degrees is defined as counterclockwise. From the body coordinate system C b Rotate to the geodetic coordinate system C e The parallel rotation matrix is: In the above formula is the gun roll angle, θ is the gun pitch angle, ψ is the gun yaw angle, s· represents sin·, c· represents cos·, and · refers to any angle; Regulation R x β, R y α represents the rotation matrix of the right-hand coordinate system rotating around the x and y axes by β and α degrees respectively; if the four rotors simultaneously produce α degrees of pitch tilt and β degrees of roll tilt, then the wing coordinate system C wi Rotate to the body coordinate system C b The parallel rotation matrix is: Step 2, construct the dynamic model of the linear motion and angular motion of the all-drive tilt-rotor integrated flying gun, including: Step 2-1: The lift generated by the rotor rotation is related to O in the rotor coordinate system. wi Z wi The axis direction is consistent, perpendicular to the rotor surface and facing outward; if the four rotors simultaneously produce α degrees of pitch tilt and β degrees of roll tilt, the total lift effect on the gun in the body coordinate system is: In the formula, F Tx 、F Ty 、F Tz They are the total lift F in the body coordinate system T The components on the x, y, and z axes, i=1,2,3,4, are the lift in the four rotor coordinate systems, C T is the lift coefficient, w i is the rotation speed of each rotor; The total lift F in the body coordinate system T Converted to the geodetic coordinate system, according to the total lift and gravity in the body coordinate system, the resultant force on the flying gun in the geodetic coordinate system is: In the formula F e is the total lift in the geodetic coordinate system, m is the mass of the gun, and g is the local gravitational acceleration; Step 2-2, the lift generated by the rotation of the rotor generates a torque relative to the center of the fuselage. After the lift is converted to the fuselage coordinate system, the torque generated by the lift in the fuselage coordinate system is as follows: Where M tx 、M ty 、M tz It is M t Components on the x, y, and z axes, the lever arm They are: d x Indicates the Y coordinate system from the rotor center to the fuselage b Axis distance, d y Indicates the coordinate system X from the rotor center to the fuselage b The distance between the axes; Step 2-3, the anti-torque moment generated by the rotor rotation is as follows in the body coordinate system: Where M qx 、M qy 、M qz It is M q The components on the x, y, and z axes, They are the anti-torque moments in the four rotor coordinate systems, C M is the anti-torque coefficient; Step 2-4, the gyroscopic torque generated by the high-speed rotation of the rotor is as follows in the body coordinate system: Where M gx 、M gy 、M gz It is M g Components on the x, y, and z axes, Ω = [pqr] T is the angular velocity of the gun body, J p It is the sum of the moments of inertia of the motor rotor and the rotor; Step 2-5, according to the Newton-Euler equation: Among them, M k =[M kx M ky M kz ] T =[qr(J z -J y )pr(J x -J z )pq(J y -J x )] T is the Coriolis and centripetal force matrix, M kx 、M ky 、M kz It is M k The components on the x, y, and z axes, N = diag([mmm J x J y J z ]) is the inertia matrix, J x , J y , J z is the moment of inertia of the flying gun rotating around three axes, is the flying gun linear velocity; In the case of small disturbance, the attitude angle change is small, and the attitude angular velocity of the flying gun is equal to the angular velocity of the body, that is, Therefore, the model of the flying gun in the geodetic coordinate system is as follows: in 2. The method according to claim 1, It is characterized in that Step 3: Design a backstepping controller based on the dynamic model of the linear motion and angular motion of the all-drive tiltrotor integrated flying gun, and clarify the virtual control output, including: Step 3-1, establish the nonlinear state space expression of the flying gun: In the formula That is, the displacement and attitude state variables of the flying gun, f 2 (x 1 ,x 2 )=N -1 [00-mg (M g -M k ) T ] T , Indicates the lift and virtual control torque on the flying gun on the x, y, and z axes, B = N -1 ; Step 3-2, design a backstepping controller and calculate the virtual control output; the virtual control output includes lift and virtual control torque; Define the error function as e 1 =x 1 -x d , x d is the expected position and posture of the flying gun, e 2 =x 2 -α, α is the virtual control quantity and the Lyapunov function is positive definite. but Pick K 1 is a sixth-order positive diagonal matrix, then Pick but Pick Where K 2 is a sixth-order positive diagonal matrix, then The back-stepping controller makes the flying gun system gradually stable. According to the backstepping controller, the virtual control torque M is obtained x 、M y 、M z and the lift F in the geodetic coordinate system ex 、F ey 、F ez , convert the lift force to the body coordinate system, the lift force in the body coordinate system is: The total lift force on the flying gun is obtained by synthesizing the components on the x, y, and z axes:

3. The method according to claim 2, It is characterized in that Step 4 requires establishing a mapping relationship between the virtual control output and the actuator output, including: Control position and posture separately; Step 4-1, the lift components of the x, y, and z axes can be obtained by the backstepping controller to determine the rotor tilt angle: Step 4-2: The virtual control torque can be obtained by the backstepping controller. Combined with the flying gun dynamics model, the mapping relationship between the virtual control output and the rotor speed is as follows: in The rotor speed distribution is as follows:

4. A fully-driven tilt-rotor integrated flying gun model, It is characterized in that The model is applied to any one of the control methods in claims 1 to 3, and the model includes: The model of the flying gun in the geodetic coordinate system is as follows: in w i , i = 1, 2, 3, 4 is the rotation speed of the four rotors of the flying gun, C T is the lift coefficient; d x The Y coordinate system from the rotor center to the fuselage b Axis distance, d y Indicates the coordinate system X from the rotor center to the fuselage b Axis distance, C M is the anti-torque coefficient; s· represents sin·, c· represents cos·, · refers to any angle, x, y, z are the displacements of the flying gun along the x, y, z axes, θ, ψ are the roll angle, pitch angle, and yaw angle of the gun, α, β are the pitch angle and roll angle of the gun rotor; m is the mass of the gun, g is the local gravity acceleration; p, q, r are the angular velocities of the gun body; J x , J y , J z is the moment of inertia of the flying gun rotating around three axes; M gx 、M gy 、M gz is the gyroscopic moment M g Components on the x, y, and z axes; M kx 、M ky 、M kz is the Coriolis centripetal moment M k Components on the x, y, and z axes.

Images