A navigation vector field-based dynamic feedback control method for target tracking of quadrotor unmanned aerial vehicles

Abstract

This invention relates to a dynamic feedback control method for target tracking of a quadrotor unmanned aerial vehicle (UAV) based on a navigation vector field. First, it constructs the error dynamic equation between the velocity components and the velocity navigation vector of the quadrotor UAV. Then, based on the construction of the extended state observer corresponding to the position loop of the quadrotor UAV, it constructs the dynamic virtual control law for the velocity of the quadrotor UAV. Next, combining the construction of the extended state observer corresponding to the attitude loop of the quadrotor UAV, it constructs the dynamic virtual control law for the attitude angle and the dynamic control law for the angular velocity of the quadrotor UAV. Finally, it constructs an anti-interference controller for the trajectory and attitude loop of the quadrotor UAV. The entire design method enables the quadrotor UAV to perform orbital tracking of maneuvering targets, overcoming problems such as parameter uncertainty and external interference. It can perform target tracking tasks even when the UAV is subjected to parameter uncertainty and external environmental interference, significantly improving the robustness, stability, and sustainability of the quadrotor UAV in performing target tracking tasks.

Description

Technical Field

[0001] This invention relates to a dynamic feedback control method for target tracking of a quadcopter unmanned aerial vehicle (UAV) based on a navigation vector field, belonging to the field of UAV target tracking technology. Background Technology

[0002] Quadcopter drones, with their advantages of high flexibility, adaptability, wide field of view, and high operational efficiency, are widely used in fields such as power line inspection, disaster relief, and the construction of detailed 3D models. Drone-based orbital tracking, a special form of quadcopter target tracking, refers to the quadcopter maintaining a certain distance from the target while circling it, i.e., flying along a trajectory with the target as the center and a set distance as the radius. It offers advantages such as improving target tracking success rate, expanding the coverage of the target environment observation area, and increasing the precision of target observation. For example, in power line inspection, quadcopters can capture multiple omnidirectional sensor images of power facilities through orbital flight, assisting technicians in improving inspection quality and efficiency. In 3D reconstruction of building facilities, quadcopters can use multi-height orbital imaging to cover the target area, helping to increase the precision of large-scale scene 3D modeling. In geological surveying and disaster relief, quadcopters can easily reach sites inaccessible to personnel or with serious safety hazards, providing workers with real-time, continuous, and accurate terrain data. In conclusion, quadcopter-based drone orbital tracking has urgent practical significance and broad research value.

[0003] There are some key problems with existing quadcopter UAV target tracking: (1) Some UAV target tracking control methods are designed based on the UAV kinematic model, without considering the characteristics of the actual dynamic model of the quadcopter UAV, including the impact of parameter uncertainty and unknown environmental interference on the quadcopter UAV target tracking controller. In fact, these interferences are not negligible in the design of the quadcopter UAV controller; (2) Some target tracking control methods cannot achieve real-time orbit tracking of the target. Orbit tracking can obtain more comprehensive information data and images of the target, while some target orbit tracking control methods require pre-planning of the target orbit trajectory, and the real-time performance and flexibility cannot be fully guaranteed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a dynamic feedback control method for target tracking of a quadrotor UAV based on navigation vector field. The method adopts a novel design and can perform target tracking tasks under the condition that the UAV is subjected to parameter uncertainty and external environmental interference, which greatly improves the robustness, stability and sustainability of the quadrotor in performing target tracking tasks.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention designs a dynamic feedback control method for target tracking of a quadrotor UAV based on a navigation vector field, and executes the following steps A to D to obtain a quadrotor UAV trajectory and attitude loop anti-interference controller, which is used to realize the quadrotor UAV's orbital tracking of a moving target;

[0006] Step A. Based on the motion / dynamics model of the quadrotor UAV, after constructing the basic target tracking model of the quadrotor UAV and combining the basic principles of vector fields, construct the error dynamic equation between the velocity components and the velocity navigation vector of the quadrotor UAV, and then proceed to Step B;

[0007] Step B. Based on the construction of the extended state observer corresponding to the position loop of the quadcopter UAV, and combined with the error dynamic equation, construct the velocity dynamic virtual control law of the quadcopter UAV, and then proceed to step C;

[0008] Step C. Based on the speed dynamic virtual control law of the quadrotor UAV, and combined with the construction of the extended state observer corresponding to the attitude loop of the quadrotor UAV, construct the attitude angle dynamic virtual control law and the angular velocity dynamic control law of the quadrotor UAV, and then proceed to step D.

[0009] Step D. Based on the attitude angle dynamic virtual control law and angular velocity dynamic control law of the quadrotor UAV, construct the trajectory and attitude loop anti-interference controller of the quadrotor UAV.

[0010] As a preferred technical solution of the present invention, step A includes the following steps A1 to A2;

[0011] Step A1. Based on the motion / dynamics model of the quadcopter UAV, construct the relative kinematic equations of the corresponding coordinates between the quadcopter UAV and the moving target, which is the basic model of quadcopter UAV target tracking, and then proceed to step A2.

[0012] Step A2. Based on the basic model of quadcopter UAV target tracking and combined with the basic principle of vector field, construct the error dynamic equation between the velocity component and the velocity navigation vector of the quadcopter UAV, and then proceed to step B.

[0013] As a preferred embodiment of the present invention, step A1 includes the following:

[0014] Step A1-1. Construct the motion / dynamics model of the quadcopter UAV as follows:

[0015]

[0016] Among them, X P =[X P,1 ,X P,2 ,X P,3] T and X v =[X v,1 ,X v,2 ,X v,3 ] T The quadcopter UAV in inertial coordinate system OeXeYeZe The position vector and velocity vector in X Θ =[X Θ,1 ,X Θ,2 ,X Θ,3 ] T and X ω =[X ω，1 ,X ω，2 ,X ω，3 ] T The quadcopter UAV in the body coordinate system o B x B y B z B The attitude angle vector and angular velocity vector are shown below. This represents the virtual control input for the dynamic position-to-velocity response of a quadcopter drone, where m is the mass of the quadcopter drone, and G = [0, 0, mg]. T Here is the gravity matrix, and g is the gravitational acceleration;

[0017] g1 = [cos(X)] Θ，3 sin(X) Θ，2 cos(X) Θ，1 )+sin(X Θ，3 sin(X) Θ，1 ),sin(X Θ，3 sin(X) Θ，2 cos(X) Θ,1 )-cos(X Θ,3 sin(X) Θ,1 ),cos(X Θ，2 cos(X) Θ，1 )] T This is the position input matrix related to the attitude motion of the quadcopter UAV; u1 represents the total lift of the quadcopter UAV propellers, U ω =[u2,u3,u4] T The torque of the quadcopter drone, u1, u2, u3, u4, and their relationships with the control input signals are: u1 = F1 + F2 + F3 + F4. u3=J θ (lF2-lF4), u4=J ψ (-cF1+cF2-cF3+cF4), where l and c are the distance from the center of mass of the quadcopter drone to the propeller motor and the torque coefficient, respectively, and F1, F2, F3, and F4 are the lift forces of the four propellers of the quadcopter drone; fv (X v )=-Π1X v / m and f ω (X ω )=-J -1 Π2X ω These are the parameterized uncertainty terms in the aerodynamic coefficients that correspond to the velocity and angular velocity of the quadrotor UAV, which cannot be precisely obtained. Π1 and Π2 are the air damping matrices for the preset position and attitude loops of the quadrotor UAV, respectively. It is a positive definite diagonal inertia matrix. J θ J ψ These are the coordinates of the quadcopter UAV in the body coordinate system. B x B y B z B The moment of inertia Δ for rolling, pitching, and yaw motions. v =[Δ v1 ,Δ v2 ,Δ v3 ] T and Δ ω =[Δ ω1 ,Δ ω2 ,Δ ω3 ] T These are the bounded environmental disturbances experienced by the position loop and attitude loop of the quadcopter UAV in three-dimensional coordinates.

[0018] Step A1-2. Define ρ = [X P,1 ,X P,2 ] T Let X be the position vector of the quadrotor UAV in the xy-plane coordinate system, where X... P,1 This represents the coordinate value of the quadcopter drone on the x-axis of the coordinate system. P,2 These are the coordinates of the quadcopter UAV on the y-axis of its coordinate system; and the definition of ρ. t =[X p,t1 ,X p,t2 ] T Let X be the position vector of the tracked target, where X is the position vector of the target. P,t1 X represents the coordinate value on the x-axis of the coordinate system corresponding to the tracked target. P,t2 It is the coordinate value on the y-axis of the coordinate system corresponding to the tracked target; thus, the relative distance between the quadcopter UAV and the moving target is constructed.

[0019] Step A1-3. Construct the positional deviation of the corresponding coordinates between the quadcopter UAV and the moving target.

[0020] Step A1-4. Construct the relative kinematic equations between the quadcopter UAV and the moving target. That is, the basic model for target tracking of quadcopter drones.

[0021] As a preferred embodiment of the present invention, step A2 includes the following:

[0022] Step A2-1. Relative kinematic equations for the corresponding coordinates between the quadcopter UAV and the moving target. Differentiate, construct

[0023] Step A2-2. Construct the velocity navigation vector σ as follows:

[0024]

[0025] Where ζ is the desired orbital radius between the quadcopter UAV and the moving target, μ is a preset positive adjustable parameter, and χ is a preset correction factor. The correction factor χ is related to the moving target's position vector ρ. t =[X p,t1 ,X p,t2 ] T The relationship is as follows:

[0026]

[0027] in,

[0028]

[0029] Step A2-3. Construct the error between the velocity components and the velocity navigation vector σ of the quadcopter UAV.

[0030] Step A2-4. Differentiate the error s to construct the error dynamic equation between the velocity components and the velocity navigation vector σ of the quadcopter UAV. Among them, F v,1 F v,2 These are the virtual control inputs for the quadcopter UAV's corresponding velocities in the x and y directions of the coordinate system.

[0031] As a preferred embodiment of the present invention, step B includes the following:

[0032] Step B1. The bounded environmental disturbance Δ experienced by the quadcopter UAV at its corresponding position ring in three-dimensional coordinates. v X, as an added state variable in the position loop of the quadrotor UAV η And the first derivative that defines the state variable. The expanded state equations for the position loop of the quadrotor UAV are constructed as follows:

[0033]

[0034] Step B2. Based on the extended state equation of the quadrotor UAV position loop, construct the extended state observer corresponding to the quadrotor UAV position loop as follows:

[0035]

[0036] in, The position vector X of the quadcopter UAV is shown below. p Quadrotor UAV velocity vector X v State variable X η The observed value, σ η It is the preset bandwidth of the extended state observer for the trajectory loop of a quadcopter UAV, and is a preset positive real number greater than zero;

[0037] Step B3. Based on the error dynamic equation, construct the control laws corresponding to the x and y directions in the trajectory loop of the quadcopter UAV. Where, k p =diag(k) p,1 ,k p,2 ) represents the gain matrix of the trajectory loop controller for a quadcopter drone, k p,1 k p,2 The x and y components of the position loop of the quadcopter drone represent the adjustable gain of the controller.

[0038] Step B4. Construct the control law F for the altitude component z in the trajectory loop of the quadcopter UAV. v,3 =-k P,3 (X P,3 -X P,t3 )-k v,3 (X v,3 -X v,t3 )-f v (X v,3 ), where X P,3 This represents the coordinate value of the quadcopter UAV on the z-axis of the coordinate system, X. P,t3 X represents the coordinate value on the z-axis of the coordinate system corresponding to the tracked target. v,3 It is the velocity value on the z-axis of the coordinate system corresponding to the movement of the quadcopter drone, X. v,t3 k represents the velocity value on the z-axis of the coordinate system corresponding to the tracked target. P,3 k represents the controller gain for the position loop height component of a quadcopter drone. v,3 It is the controller gain for the altitude component of the speed loop of a quadcopter drone, f v (X v,3 ) represents the parameterized uncertainty term in the aerodynamic coefficient of the position loop height component of a quadcopter UAV that cannot be precisely obtained;

[0039] Step B5. According to F v =[F v,1 F v,2 F v,3 ] T To obtain the virtual control input F corresponding to the speed of the quadcopter drone v This means obtaining the speed dynamic virtual control law for the quadcopter drone.

[0040] As a preferred embodiment of the present invention, step C includes the following:

[0041] Step C1. Based on the speed dynamic virtual control law of the quadcopter UAV, construct F v The relationship between the magnitude and the total lift u1 of the quadcopter drone's propeller is as follows:

[0042]

[0043] Where u1 represents the total lift of the quadcopter drone's propellers. θ d ψ d These represent the desired roll angle, desired pitch angle, and desired yaw angle of the quadcopter UAV, respectively, generated by the speed loop control signal.

[0044] Step C2. Based on the operator's set yaw angle ψ d Then the total lift u1 of the quadcopter drone propeller and the desired roll angle Desired pitch angle θ d as follows:

[0045]

[0046] Step C3. Based on the vector formed by the desired roll angle, desired pitch angle, and desired yaw angle of the quadcopter UAV generated by the speed loop control signal. Constructing the attitude angle tracking error vector of a quadcopter UAV

[0047] Step C4. Construct the dynamic virtual control law for the attitude angles of the quadcopter UAV as follows:

[0048]

[0049] Where, α ω k represents the attitude angle control vector corresponding to the quadcopter UAV. Θ =diag(k) Θ,1 ,k Θ,2 ,k Θ,3 ) represents the gain matrix of the attitude angle controller for a quadcopter drone, k Θ,1 k Θ,2 kΘ,3 These represent the adjustable gains of the controller corresponding to the three components of the quadcopter drone's attitude angle;

[0050] Step C5. The bounded environmental disturbance Δ experienced by the quadcopter UAV in three-dimensional coordinates corresponding to its attitude loop. ω X, as an added state variable in the attitude loop of the quadcopter UAV γ =Δ ω And the first derivative that defines the state variable. The extended state equations for the attitude loop of the quadrotor UAV are constructed as follows:

[0051]

[0052] Step C6. Based on the extended state equation of the quadrotor UAV attitude loop, construct the extended state observer corresponding to the quadrotor UAV attitude loop as follows:

[0053]

[0054] in, The attitude angle vectors X and X of the quadcopter UAV are respectively. Θ Angular velocity vector X of quadcopter UAV ω State variable X γ State observations, σ γ It is the preset bandwidth of the extended state observer corresponding to the attitude loop of the quadcopter UAV, which is a preset positive real number greater than zero;

[0055] Step C7. Construct the quadcopter UAV angular velocity tracking error vector e ω =X ω -α ω Therefore, the dynamic control law for the angular velocity of the quadcopter UAV is constructed as follows:

[0056]

[0057] Among them, U ω k represents the angular velocity loop control vector corresponding to the quadcopter UAV. ω =diag{k ω1 ,k ω2 ,k ω3} represents the gain matrix of the quadcopter drone's angular velocity controller, k ω,1 k ω,2 k ω,3 These represent the adjustable gains of the controller corresponding to the three components of the quadcopter drone's angular velocity.

[0058] The present invention provides a dynamic feedback control method for target tracking of a quadrotor UAV based on a navigation vector field. Compared with existing technologies, the above technical solution has the following technical advantages:

[0059] This invention presents a dynamic feedback control method for target tracking of a quadrotor UAV based on a navigation vector field. First, a basic model of quadrotor UAV target tracking is constructed, and based on the fundamental principles of vector fields, an error dynamic equation is built between the velocity components and the velocity navigation vector of the quadrotor UAV. Next, based on the construction of the extended state observer corresponding to the position loop of the quadrotor UAV, and combined with the error dynamic equation, a dynamic virtual control law for the velocity of the quadrotor UAV is constructed. Then, based on the construction of the extended state observer corresponding to the attitude loop of the quadrotor UAV, dynamic virtual control laws for the attitude angle and dynamic control laws for the angular velocity of the quadrotor UAV are constructed. Finally, based on the dynamic virtual control laws for the attitude angle and dynamic control laws for the angular velocity of the quadrotor UAV, an anti-interference controller for the trajectory and attitude loop of the quadrotor UAV is constructed. The entire design method enables the quadrotor UAV to perform orbital tracking of maneuvering targets, overcoming problems such as parameter uncertainty and external interference. It can perform target tracking tasks even when the UAV is subjected to parameter uncertainty and external environmental interference, significantly improving the robustness, stability, and sustainability of the quadrotor UAV in performing target tracking tasks. Attached Figure Description

[0060] Figure 1 This is a control structure block diagram of the target tracking dynamic feedback control method for quadrotor UAVs based on navigation vector fields designed in this invention;

[0061] Figure 2 This is a schematic diagram of the three-dimensional trajectory of a quadcopter UAV target tracking in an inertial coordinate system.

[0062] Figure 3 This is a schematic diagram of the XY plane trajectory of a quadcopter UAV target tracking in an inertial coordinate system.

[0063] Figure 4 This is a schematic diagram of the position response curve of a quadcopter drone;

[0064] Figure 5 This is a schematic diagram of the interference estimation of the extended state observer corresponding to the position loop of a quadcopter UAV;

[0065] Figure 6 This is a schematic diagram of the disturbance estimation of the extended state observer corresponding to the attitude loop of a quadcopter UAV. Detailed Implementation

[0066] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0067] This invention designs a dynamic feedback control method for target tracking of a quadrotor UAV based on navigation vector fields. In practical applications, based on... Figure 1As shown, the specific design executes the following steps A to D to obtain the quadcopter UAV trajectory and attitude loop anti-interference controller, which is used to realize the quadcopter UAV's orbital tracking of moving targets.

[0068] Step A. Based on the quadrotor UAV motion / dynamics model, after constructing the basic model of quadrotor UAV target tracking, and combining the basic principles of vector fields, construct the error dynamic equation between the quadrotor UAV velocity components and the velocity navigation vector, and then proceed to Step B.

[0069] In practical applications, the above step A is specifically designed to be executed as follows: steps A1 to A2.

[0070] Step A1. Based on the quadcopter UAV motion / dynamics model, construct the relative kinematic equations of the corresponding coordinates between the quadcopter UAV and the moving target, which is the basic model of quadcopter UAV target tracking, and then proceed to step A2.

[0071] Step A1. In practical applications, the specific execution is as follows.

[0072] Step A1-1. Construct the motion / dynamics model of the quadcopter UAV as follows:

[0073]

[0074] Among them, X P =[X P,1 ,X P,2 ,X P,3 ] T and X v =[X v,1 ,X v,2 ,X v,3 ] T The quadcopter UAV in inertial coordinate system O e X e Y e Z e The position vector and velocity vector in X Θ =[X Θ,1 ,X Θ,2 ,X Θ,3 ] T and X ω =[X ω，1 ,X ω，2 ,X ω，3 ] T The quadcopter UAV in the body coordinate system o B x B y B z B The attitude angle vector and angular velocity vector are shown below. This represents the virtual control input for the dynamic position-to-velocity response of a quadcopter drone, where m is the mass of the quadcopter drone, and G = [0, 0, mg]. T Let g be the gravity matrix, and g be the gravitational acceleration.

[0075] g1 = [cos(X)] Θ，3 sin(X) Θ，2 cos(X) Θ，1 )+sin(X Θ，3 sin(X) Θ，1 ),sin(X Θ，3 sin(X) Θ，2 cos(X) Θ,1 )-cos(X Θ,3 sin(X) Θ,1 ),cos(X Θ，2 cos(X) Θ，1 )] T This is the position input matrix related to the attitude motion of the quadcopter UAV; u1 represents the total lift of the quadcopter UAV propellers, U ω =[u2,u3,u4] T The torque of the quadcopter drone, u1, u2, u3, u4, and their relationships with the control input signals are: u1 = F1 + F2 + F3 + F4. u3=J θ (lF2-lF4), u4=J ψ (-cF1+cF2-cF3+cF4), where l and c are the distance from the center of mass of the quadcopter drone to the propeller motor and the torque coefficient, respectively, and F1, F2, F3, and F4 are the lift forces of the four propellers of the quadcopter drone; f v (X v )=-Π1X v / m and f ω (X ω )=-J -1 Π2X ω These are the parameterized uncertainty terms in the aerodynamic coefficients that correspond to the velocity and angular velocity of the quadrotor UAV, which cannot be precisely obtained. Π1 and Π2 are the air damping matrices for the preset position and attitude loops of the quadrotor UAV, respectively. It is a positive definite diagonal inertia matrix. J θ J ψ These are the coordinates of the quadcopter UAV in the body coordinate system. B x B y B z B The moment of inertia Δ for rolling, pitching, and yaw motions. v =[Δ v1 ,Δ v2,Δ v3 ] T and Δ ω =[Δ ω1 ,Δ ω2 ,Δ ω3 ] T These are the bounded environmental disturbances experienced by the position loop and attitude loop of the quadcopter UAV in three-dimensional coordinates.

[0076] Step A1-2. Define ρ = [X P,1 ,X P,2 ] T Let X be the position vector of the quadrotor UAV in the xy-plane coordinate system, where X... P,1 This represents the coordinate value of the quadcopter drone on the x-axis of the coordinate system. P,2 These are the coordinates of the quadcopter UAV on the y-axis of its coordinate system; and the definition of ρ. t =[X p,t1 ,X p,t2 ] T Let X be the position vector of the tracked target, where X is the position vector of the target. P,t1 X represents the coordinate value on the x-axis of the coordinate system corresponding to the tracked target. P,t2 It is the coordinate value on the y-axis of the coordinate system corresponding to the tracked target; thus, the relative distance between the quadcopter UAV and the moving target is constructed.

[0077] Step A1-3. Construct the positional deviation of the corresponding coordinates between the quadcopter UAV and the moving target.

[0078] Step A1-4. Construct the relative kinematic equations between the quadcopter UAV and the moving target. That is, the basic model for target tracking of quadcopter drones.

[0079] Step A2. Based on the basic target tracking model of the quadcopter UAV, and combined with the vector field constructed based on the Lyapunov stability principle, construct the error dynamic equation between the velocity component and the velocity navigation vector of the quadcopter UAV, and then proceed to step B.

[0080] Step A2 is executed as follows.

[0081] Step A2-1. Relative kinematic equations for the corresponding coordinates between the quadcopter UAV and the moving target. Differentiate, construct

[0082] Step A2-2. Construct the velocity navigation vector σ as follows:

[0083]

[0084] Where ζ is the desired orbital radius between the quadcopter UAV and the moving target, μ is a preset positive adjustable parameter, and χ is a preset correction factor. The correction factor χ is related to the moving target's position vector ρ. t =[X p,t1 ,X p,t2 ] T The relationship is as follows:

[0085]

[0086] in,

[0087]

[0088] Step A2-3. Construct the error between the velocity components and the velocity navigation vector σ of the quadcopter UAV.

[0089] Step A2-4. Differentiate the error s to construct the error dynamic equation between the velocity components and the velocity navigation vector σ of the quadcopter UAV. Among them, F v,1 F v,2 These are the virtual control inputs for the quadcopter UAV's corresponding velocities in the x and y directions of the coordinate system.

[0090] Step B. Based on the construction of the extended state observer corresponding to the position loop of the quadrotor UAV, and combined with the error dynamic equation, construct the speed dynamic virtual control law of the quadrotor UAV, that is, the quadrotor UAV trajectory loop anti-interference controller, and then proceed to step C.

[0091] In practical applications, step B above is specifically executed as steps B1 to B5.

[0092] Step B1. The bounded environmental disturbance Δ experienced by the quadcopter UAV at its corresponding position ring in three-dimensional coordinates. v X, as an added state variable in the position loop of the quadrotor UAV η And the first derivative that defines the state variable. The expanded state equations for the position loop of the quadrotor UAV are constructed as follows:

[0093]

[0094] Step B2. Based on the extended state equation of the quadrotor UAV position loop, construct the extended state observer corresponding to the quadrotor UAV position loop as follows:

[0095]

[0096] in, The position vector X of the quadcopter UAV is shown below.p Quadrotor UAV velocity vector X v State variable X η The observed value, σ η It is the preset bandwidth of the extended state observer for the trajectory loop of a quadcopter UAV, and is a preset positive real number greater than zero.

[0097] Step B3. Based on the error dynamic equation, construct the control laws corresponding to the x and y directions in the trajectory loop of the quadcopter UAV. Where, k p =diag(k) p,1 ,k p,2 ) represents the gain matrix of the trajectory loop controller for a quadcopter drone, k p,1 k p,2 The x and y components of the position loop of the quadcopter drone represent the adjustable gain of the controller.

[0098] Step B4. Construct the control law F for the altitude component z in the trajectory loop of the quadcopter UAV. v,3 =-k P,3 (X P,3 -X P,t3 )-k v,3 (X v,3 -X v,t3 )-f v (X v,3 ), where X P,3 This represents the coordinate value of the quadcopter UAV on the z-axis of the coordinate system, X. P,t3 X represents the coordinate value on the z-axis of the coordinate system corresponding to the tracked target. v,3 It is the velocity value on the z-axis of the coordinate system corresponding to the movement of the quadcopter drone, X. v,t3 k represents the velocity value on the z-axis of the coordinate system corresponding to the tracked target. P,3 k represents the controller gain for the position loop height component of a quadcopter drone. v,3 It is the controller gain for the altitude component of the speed loop of a quadcopter drone, f v (X v,3 ) represents the parameterized uncertainty term in the aerodynamic coefficient of the position loop height component of a quadrotor UAV that cannot be precisely obtained.

[0099] Step B5. According to F v =[F v,1 F v,2 F v,3 ] T To obtain the virtual control input F corresponding to the speed of the quadcopter drone v This means obtaining the speed dynamic virtual control law for the quadcopter drone.

[0100] Step C. Based on the speed dynamic virtual control law of the quadcopter UAV, and combined with the construction of the extended state observer corresponding to the attitude loop of the quadcopter UAV, construct the attitude angle dynamic virtual control law and the angular velocity dynamic control law of the quadcopter UAV, and then proceed to step D.

[0101] In practical applications, step C above is specifically executed as steps C1 to C7.

[0102] Step C1. Based on the speed dynamic virtual control law of the quadcopter UAV, construct F v The relationship between the magnitude and the total lift u1 of the quadcopter drone's propeller is as follows:

[0103]

[0104] Where u1 represents the total lift of the quadcopter drone's propellers. θ d ψ d These represent the desired roll angle, desired pitch angle, and desired yaw angle of the quadcopter UAV, respectively, generated by the speed loop control signal.

[0105] Step C2. Based on the operator's set yaw angle ψ d Then the total lift u1 of the quadcopter drone propeller and the desired roll angle Desired pitch angle θ d as follows:

[0106]

[0107] Step C3. Based on the vector formed by the desired roll angle, desired pitch angle, and desired yaw angle of the quadcopter UAV generated by the speed loop control signal. Constructing the attitude angle tracking error vector of a quadcopter UAV

[0108] Step C4. Construct the dynamic virtual control law for the attitude angles of the quadcopter UAV as follows:

[0109]

[0110] Where, α ω k represents the attitude angle control vector corresponding to the quadcopter UAV. Θ =diag(k) Θ,1 ,k Θ,2 ,k Θ,3 ) represents the gain matrix of the attitude angle controller for a quadcopter drone, k Θ,1 k Θ,2 k Θ,3 These represent the adjustable gains of the controller corresponding to the three components of the quadcopter drone's attitude angle.

[0111] Step C5. The bounded environmental disturbance Δ experienced by the quadcopter UAV in three-dimensional coordinates corresponding to its attitude loop. ω X, as an added state variable in the attitude loop of the quadcopter UAV γ =Δ ω And the first derivative that defines the state variable. The extended state equations for the attitude loop of the quadrotor UAV are constructed as follows:

[0112]

[0113] Step C6. Based on the extended state equation of the quadrotor UAV attitude loop, construct the extended state observer corresponding to the quadrotor UAV attitude loop as follows:

[0114]

[0115] in, The attitude angle vectors X and X of the quadcopter UAV are respectively. Θ Angular velocity vector X of quadcopter UAV ω State variable X γ State observations, σ γ It is the preset bandwidth of the extended state observer corresponding to the attitude loop of the quadcopter UAV, and is a preset positive real number greater than zero.

[0116] Step C7. Construct the quadcopter UAV angular velocity tracking error vector e ω =X ω -α ω Therefore, the dynamic control law for the angular velocity of the quadcopter UAV is constructed as follows:

[0117]

[0118] Among them, U ω k represents the angular velocity loop control vector corresponding to the quadcopter UAV. ω =diag{k ω1 ,k ω2 ,k ω3} represents the gain matrix of the quadcopter drone's angular velocity controller, k ω,1 k ω,2 k ω,3 These represent the adjustable gains of the controller corresponding to the three components of the quadcopter drone's angular velocity.

[0119] Step D. Based on the attitude angle dynamic virtual control law and angular velocity dynamic control law of the quadrotor UAV, construct the trajectory and attitude loop anti-interference controller of the quadrotor UAV.

[0120] The above-designed dynamic feedback control method for target tracking of a quadrotor UAV based on navigation vector fields was applied in practice. The initial position and velocity of the quadrotor UAV are as follows:

[0121] [X p,1 ,X p,2 ,X p,3 ,X v,1 ,X v,2 ,X v,3 ] = [0,0,0,0,0,0]

[0122] The trajectory of the tracked target is as follows:

[0123]

[0124] Set external disturbance:

[0125]

[0126]

[0127] To achieve better controller performance, the position loop observer bandwidth σ is selected. η =7, Attitude loop observer bandwidth σ γ =15, Gain k of the quadcopter drone trajectory loop controller p =diag(k) p,1 ,k p,2 =diag(2,2), where k is the gain k of the position loop altitude component controller in the trajectory loop of a quadcopter UAV. p,3 =5, Gain k of the velocity loop altitude component controller in the trajectory loop of a quadcopter UAV v,3 =2.5, adjustable parameter μ=5, orbital radius ζ=3, quadcopter UAV attitude angle controller gain k Θ =diag(k) Θ,1 ,k Θ,2 ,k Θ,3 =diag(20,20,20), where k is the gain of the quadcopter drone's angular velocity controller. ω =diag{k ω1 ,k ω2 ,k ω3} = diag{10,10,10}.

[0128] Based on this, in practical applications, steps A to D are executed sequentially to obtain the quadcopter UAV attitude loop anti-interference controller, which is used to realize the quadcopter UAV's orbital tracking of a moving target. In practical applications, the three-dimensional trajectory of the quadcopter UAV target tracking in the inertial coordinate system is shown in the figure below. Figure 2 As shown in the figure, the XY plane trajectory of a quadcopter UAV target tracking in the inertial coordinate system is illustrated in the figure. Figure 3 As shown in the figure, the position response curve of the quadcopter UAV is illustrated in the figure. Figure 4 As shown, the disturbance estimation of the extended state observer corresponding to the position loop of the quadcopter UAV is illustrated in the figure. Figure 5 As shown, the disturbance estimation of the extended state observer corresponding to the attitude loop of the quadcopter UAV is illustrated in the figure below. Figure 6 As shown.

[0129] The aforementioned technical solution presents a dynamic feedback control method for target tracking of a quadrotor UAV based on a navigation vector field. First, a basic model of quadrotor UAV target tracking is constructed, and based on the fundamental principles of vector fields, an error dynamic equation is built between the velocity components and the velocity navigation vector of the quadrotor UAV. Next, based on the construction of the extended state observer corresponding to the position loop of the quadrotor UAV, and combined with the error dynamic equation, a dynamic virtual control law for the velocity of the quadrotor UAV is obtained. Then, based on the construction of the extended state observer corresponding to the attitude loop of the quadrotor UAV, dynamic virtual control laws for the attitude angle and dynamic control laws for the angular velocity of the quadrotor UAV are obtained. Finally, based on the dynamic virtual control laws for the attitude angle and dynamic control laws for the angular velocity of the quadrotor UAV, an anti-interference controller for the trajectory and attitude loop of the quadrotor UAV is constructed. This entire design method enables the quadrotor UAV to perform orbital tracking of maneuvering targets, overcoming problems such as parameter uncertainty and external interference. It can perform target tracking tasks even when the UAV is subjected to parameter uncertainty and external environmental interference, significantly improving the robustness, stability, and sustainability of the quadrotor UAV in performing target tracking tasks.

[0130] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A dynamic feedback control method for target tracking of a quadrotor unmanned aerial vehicle based on a navigation vector field, characterized in that: Perform steps A to D to obtain the quadcopter UAV trajectory and attitude loop anti-interference controller, which is used to realize the quadcopter UAV's orbital tracking of moving targets. Step A. Based on the motion / dynamics model of the quadrotor UAV, after constructing the basic target tracking model of the quadrotor UAV and combining the basic principles of vector fields, construct the error dynamic equation between the velocity components and the velocity navigation vector of the quadrotor UAV, and then proceed to Step B; Step B. Based on the construction of the extended state observer corresponding to the position loop of the quadcopter UAV, and combined with the error dynamic equation, construct the velocity dynamic virtual control law of the quadcopter UAV, and then proceed to step C; Step C. Based on the speed dynamic virtual control law of the quadrotor UAV, and combined with the construction of the extended state observer corresponding to the attitude loop of the quadrotor UAV, construct the attitude angle dynamic virtual control law and the angular velocity dynamic control law of the quadrotor UAV, and then proceed to step D; Step D. Based on the attitude angle dynamic virtual control law and angular velocity dynamic control law of the quadrotor UAV, construct the trajectory and attitude loop anti-interference controller of the quadrotor UAV; Step A includes the following steps A1 to A2; Step A1. Based on the motion / dynamics model of the quadcopter UAV, construct the relative kinematic equations of the corresponding coordinates between the quadcopter UAV and the moving target, which is the basic model of quadcopter UAV target tracking, and then proceed to step A2. Step A2. Based on the basic model of target tracking for quadrotor UAVs and combined with the basic principles of vector fields, construct the error dynamic equation between the velocity components and the velocity navigation vector of the quadrotor UAV, and then proceed to step B; Step A1 includes the following: Step A1-1. Construct the motion / dynamics model of the quadcopter drone as follows: ； in, and The quadcopter UAV in inertial coordinate system The position vector and velocity vector in the middle. and The quadcopter UAV in the body coordinate system The attitude angle vector and angular velocity vector are shown below. The virtual control input represents the dynamic position-to-velocity response of a quadcopter drone, where, For the mass of the quadcopter drone, Here is the gravity matrix, and g is the gravitational acceleration; It is the position input matrix related to the attitude motion of the quadcopter UAV; This represents the total lift of the propellers of a quadcopter drone. It is the torque of the quadcopter drone. , , , The relationship between each signal and the control input signal: , , , ,in, and These represent the distance from the center of mass of the quadcopter drone to the propeller motor and the torque coefficient, respectively. These are the lift generated by the four propellers of the quadcopter drone; and These are the parameterized uncertainty terms in the aerodynamic coefficients that correspond to the velocity and angular velocity of the quadcopter UAV, respectively, which cannot be precisely obtained. , These are the air damping matrices for the preset position and attitude loops of the quadcopter drone. It is a positive definite diagonal inertia matrix. These are the quadcopter drones in the body coordinate system. The moment of inertia for rolling, pitching, and yaw motions. and These are the bounded environmental disturbances experienced by the position loop and attitude loop of the quadcopter UAV in three-dimensional coordinates. Step A1-2. Definition Let be the position vector of the quadrotor UAV in the xy-plane coordinate system, where . This represents the coordinate value of the quadcopter drone on the x-axis of the coordinate system. These are the coordinates of the quadcopter UAV on the y-axis of its coordinate system; and the definition. Let be the position vector of the tracked target, where The coordinates of the tracked target on the x-axis of the coordinate system. It is the coordinate value on the y-axis of the coordinate system corresponding to the tracked target; thus, the relative distance between the quadcopter UAV and the moving target is constructed. ; Step A1-3. Construct the positional deviation of the corresponding coordinates between the quadcopter UAV and the moving target. ; Step A1-4. Construct the relative kinematic equations of the corresponding coordinates between the quadcopter UAV and the moving target. This refers to the basic model for target tracking of quadcopter drones. Step A2 includes the following: Step A2-1. Relative kinematic equations for the corresponding coordinates between the quadcopter UAV and the moving target. Differentiate, construct ; Step A2-2. Construct the velocity navigation vector as follows: ； in, The desired orbital radius between the quadcopter drone and the moving target. These are preset, positively adjustable parameters; For the preset correction factor, the correction factor With the moving target position vector The relationship is as follows: ； in, , ； Step A2-3. Construct the velocity components and velocity navigation vector of the quadcopter UAV. Error between ; Step A2-4. Regarding the error Differentiate and construct the velocity components and velocity navigation vector of the quadcopter UAV. Error dynamic equation between ,in, , These are the virtual control inputs for the quadcopter UAV's corresponding velocities in the x and y directions of the coordinate system.

2. The method for dynamic feedback control of target tracking of a quadrotor UAV based on a navigation vector field according to claim 1, characterized in that, Step B includes the following: Step B1. The bounded environmental disturbances experienced by the quadcopter UAV at its corresponding position ring in three-dimensional coordinates. As a state variable added to the position loop of the quadcopter UAV And the first derivative that defines the state variable. The extended state equations of the position loop for the quadrotor UAV are constructed as follows: ； Step B2. Based on the extended state equation of the quadrotor UAV position loop, construct the extended state observer corresponding to the quadrotor UAV position loop as follows: ； in, , , These are the position vectors of the quadcopter UAV. Quadrotor UAV velocity vector State variables The observed values, It is the preset bandwidth of the extended state observer for the trajectory loop of a quadcopter UAV, and is a preset positive real number greater than zero; Step B3. Based on the error dynamic equation, construct the control laws corresponding to the x and y directions in the trajectory loop of the quadcopter UAV. ;in, This represents the gain matrix of the trajectory loop controller for a quadcopter drone. The x and y components of the position loop of the quadcopter drone represent the adjustable gain of the controller. Step B4. Construct the control law for the altitude component z in the trajectory loop of the quadcopter UAV as follows: ,in, This represents the coordinate value on the z-axis of the coordinate system corresponding to the quadcopter UAV. The coordinates of the tracked target on the z-axis of the coordinate system. It is the velocity value on the z-axis of the corresponding coordinate system when the quadcopter drone is moving. The velocity value on the z-axis of the coordinate system corresponding to the tracked target. The controller gain represents the position loop height component of the quadcopter drone. It is the controller gain for the altitude component of the speed loop of a quadcopter drone. This is a parameterized uncertainty term in the aerodynamic coefficient of the position loop height component of a quadrotor UAV that cannot be precisely obtained. Step B5. According to To obtain the virtual control input corresponding to the speed of the quadcopter drone This means obtaining the speed dynamic virtual control law for the quadcopter drone.

3. The method for dynamic feedback control of target tracking of a quadrotor UAV based on a navigation vector field according to claim 2, characterized in that, Step C includes the following: Step C1. Based on the speed dynamic virtual control law of the quadcopter UAV, construct... Size and total lift of the quadcopter drone propeller The relationship is as follows: ； in, This represents the total lift of the propellers of a quadcopter drone. , , These represent the desired roll angle, desired pitch angle, and desired yaw angle of the quadcopter UAV, respectively, generated by the speed loop control signal. Step C2. Based on the operator's set yaw angle The total lift of the quadcopter drone's propellers and expected roll angle Desired pitch angle as follows: ； Step C3. Based on the vector formed by the desired roll angle, desired pitch angle, and desired yaw angle of the quadcopter UAV generated by the speed loop control signal. Construct the attitude angle tracking error vector of a quadcopter UAV ; Step C4. Construct the dynamic virtual control law for the attitude angles of the quadcopter UAV as follows: ； in, This represents the attitude angle control vector for the quadcopter drone. This represents the gain matrix of the attitude angle controller for a quadcopter drone. These represent the adjustable gains of the controller corresponding to the three components of the quadcopter drone's attitude angle; Step C5. Bounded environmental disturbances experienced by the quadcopter UAV in three-dimensional coordinates, corresponding to its attitude loop. As an added state variable in the attitude loop of the quadcopter UAV And the first derivative that defines the state variable. The extended state equations of the attitude loop for the quadrotor UAV are constructed as follows: ； Step C6. Based on the extended state equation of the quadrotor UAV attitude loop, construct the extended state observer corresponding to the quadrotor UAV attitude loop as follows: ； in, , , These are the attitude angle vectors of the quadcopter UAV. Angular velocity vector of quadcopter UAV State variables State observations, It is the preset bandwidth of the extended state observer corresponding to the attitude loop of the quadcopter UAV, which is a preset positive real number greater than zero; Step C7. Construct the angular velocity tracking error vector for the quadcopter UAV. Therefore, the dynamic control law for the angular velocity of the quadcopter UAV is constructed as follows: ； in, This represents the angular velocity loop control vector corresponding to the quadcopter drone. This represents the gain matrix of the angular velocity controller for a quadcopter drone. These represent the adjustable gains of the controller corresponding to the three components of the quadcopter drone's angular velocity.

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