A containment control method based on multi-UUV system

Abstract

The present invention discloses a containment control method based on a multi-UUV system, which specifically includes the following steps: S1, obtaining a cluster of underwater unmanned vehicles (UUVs) and constructing a kinematic model and a dynamic model of each UUV; S2, collecting the state information of the navigators of the UUV cluster and initializing them; S3, setting a virtual reference point and designing a control protocol based on the UUV cluster, wherein the control protocol includes a containment control protocol and an inclusion control protocol; S4, designing a path tracking controller using the navigator state information and the kinematic model and the dynamic model; S5, completing the path tracking of a single UUV according to the control protocol and the path tracking controller, obtaining the desired formation and maintaining the formation to navigate to the target area, thereby realizing containment control based on the multi-UUV system.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle control, and in particular relates to a containment control method based on a multi-UUV system. Background Art

[0002] Formation control of unmanned underwater vehicles (UUVs) is a core capability for ocean exploration. With the deepening of research on UUV swarms, centralized leader-follower control structures can maintain formation consistency, but they suffer from significant communication difficulties and computational overhead. The characteristic of containment control is that it achieves overall control with minimal control nodes. In large swarms, safety issues also need to be considered. Inclusive control can address this issue. A small number of UUVs equipped with high-performance sensors form a safe zone to monitor the surrounding environment. When danger arises, a safe area is mapped out. The remaining UUVs, guided by control rates, enter this area and successfully cross the dangerous zone. While containment control can address the problem of consistent control in large swarms, underwater interference can make formation formation more difficult and time-consuming if all units in the formation are required to maintain consistency. In this case, inclusive control strategies are needed to address this issue. Instead of forming a highly precise formation all at once, a rough formation can be generated, forming a loose formation. This can reduce the formation time, and containment control has great potential in realizing large-scale UUV formations. Therefore, a containment control method based on a multi-UUV system is urgently needed to address the shortcomings of existing technologies. Summary of the Invention

[0003] The purpose of this invention is to propose a containment control method based on a multi-UUV system. The containment control protocol is used to effectively reduce the communication difficulty and computational complexity of the system, improve the control performance and robustness of the system, and meet the time constraints of position, velocity, and attitude for three-dimensional trajectory tracking of underactuated UUVs.

[0004] To achieve the above objectives, the present invention provides a containment control method based on a multi-UUV system, which specifically includes the following steps:

[0005] S1. Obtain a cluster of underwater unmanned vehicles (UUVs) and construct kinematic and dynamic models for each UUV.

[0006] S2. Collecting the navigator status information of the UUV cluster and initializing it;

[0007] S3. Setting a virtual reference point and designing a control protocol based on the UUV cluster, wherein the control protocol includes a containment control protocol and an inclusion control protocol;

[0008] S4. Designing a path tracking controller using the navigator state information, the kinematic model, and the dynamic model;

[0009] S5. Complete the path tracking of a single UUV according to the control protocol and the path tracking controller, obtain the desired formation and maintain the formation to navigate to the target area, and realize the containment control based on the multi-UUV system.

[0010] Optionally, the underwater unmanned vehicle (UUV) cluster includes a first-level leader, a second-level leader, and a follower.

[0011] Optionally, the kinematic model is:

[0012]

[0013] The kinetic model is:

[0014]

[0015] in, is the differential of the north coordinate, u is the longitudinal velocity, ψ is the heading angle, θ is the pitch angle, v is the lateral velocity, is the differential of the easting coordinate, is the differential of the depth coordinate, is the differential of the pitch angle, q is the pitch angular velocity, is the differential of the heading angle, r is the yaw angular velocity, is the differential of the longitudinal velocity, m is the weight of the UUV, Respectively represent the differentials of the external forces X, Y, and N on the hull velocities u, v, and r, w is the velocity in the direction perpendicular to the deck, τ u is the longitudinal thrust, t is the time, T′=[T′1,0,0,T′2,T′3] T is the unknown bounded time delay of the input of the longitudinal, pitch and bow actuators in the rigid coordinate system, ω=[ω u ,ω v ,ω w ,ω q ,ω r ] T For unknown bounded interference in the environment, is the differential of the transverse velocity, is the differential of the velocity in the direction perpendicular to the deck, is the differential of the pitch angular velocity, Iy For Y b The moment of inertia of the shaft, represents the differential of the external force M to the hull velocity u, B is the buoyancy of the UUV, is the longitudinal metacenter height, τ q is the thrust in the direction of the pitch angle, is the differential of the heading angular velocity, I z For Z b Moment of inertia of the shaft, τ r is the bow thrust, X u 、X u|u| 、Y v 、Y v|v| 、Z w 、Z w|w| 、M q 、M q|q| 、N r 、N r|r| is the hydrodynamic damping coefficient.

[0016] Optionally, the navigator status information includes position information, attitude information and speed information.

[0017] Optionally, the containment control protocol includes a first-level navigator control protocol, a second-level navigator control protocol, and a follower control protocol;

[0018] The first-level pilot control protocol is:

[0019]

[0020] here And right Set the following protocol:

[0021]

[0022] The secondary pilot control protocol is:

[0023]

[0024] The follower control protocol is:

[0025]

[0026] in, is the differential of the desired position, is the desired speed, x di is the desired horizontal position, y di is the expected longitudinal position, T is the transposition, is a real number, is the change in the desired lateral position, is the change in the desired longitudinal position, is the sum of some elements of the matrix, k is the weight constant, j is the jth neighbor aircraft, a ij is the element in row i and column j in the adjacency matrix, are the expected value of its own estimation and the expected value of its neighbors, d j d i are the relative distance to itself and the relative distance to its neighbors, k c is a constant, sgn(·) is a sign function, is the change in the relative distance of neighbors, Γ is the containment rate, c is a constant, representing whether the current node spacecraft is restrained by the first-level navigator, i is the current spacecraft, and N is the set of restrained nodes. is the set of non-pinned nodes, is the change in the expected position of the neighbor.

[0027] Optionally, the inclusion control protocol is:

[0028]

[0029] Among them, L f1 is the Laplace matrix between the first-level and second-level leaders, d f is the in-degree of the degree matrix, L f2 is the Laplace matrix between the two-level leaders, I2 is the identity matrix, p l is the position of the navigator, p f The position of the follower.

[0030] Optionally, designing the path tracking controller using the navigator state information and the kinematic model and the dynamic model includes:

[0031] According to the pilot state information, a non-singular terminal sliding surface is designed and obtained. The sliding surface is:

[0032]

[0033] Through the sliding surface, the derivative of the sliding surface is obtained as:

[0034]

[0035] Importing the dynamic model and the kinematic model into the derivatives of the sliding surface respectively to obtain the path tracking controller;

[0036] The path tracking controller is:

[0037]

[0038] The path tracking controller includes a dynamic path tracking controller and a kinematic path tracking controller;

[0039] Among them, s i1 is the sliding surface, u ei is the speed tracking error, c1 is a positive real number, p1 and q1 are both positive odd numbers, and 1<p1 / q1<2, is the derivative of the sliding surface, is the change in longitudinal velocity, Expected change in longitudinal velocity, v i is the speed, r i is the heading angular velocity, d 11 =-X u -X u|u| |u|,X u represents the differential of the external force X to the hull velocity u, X u|u| is the higher-order term after Taylor expansion, u i is the longitudinal velocity, τ i1 For longitudinal thrust.

[0040] Optionally, the dynamic path tracking controller is:

[0041]

[0042] Among them, k1 is the weight.

[0043] Optionally, the kinematic path tracking controller is:

[0044]

[0045] Among them, τ i3 is the bow thrust, d 33 =-N r -N r|r| |r|,N r Represents the differential of the external force N to the hull velocity r, N r|r| is the higher-order term after Taylor expansion, is the desired heading angular acceleration, q2 is an odd number greater than zero, c2 is a constant greater than zero, p2 is an odd number greater than zero, is the error between the heading angular velocity and the expected value, k2 is the weight, s i2 is the sliding surface.

[0046] Optionally, completing the path tracking of a single UUV according to the control protocol and the path tracking controller, obtaining the desired formation, and maintaining the formation to navigate to the target area includes:

[0047] Complete path tracking of a single UUV according to the control protocol and the path tracking controller to obtain a formation result;

[0048] determining whether the formation result satisfies an expected formation, and if the formation result satisfies the expected formation, continuing to maintain the formation result until the formation reaches a target area;

[0049] When the formation result does not form the expected formation, the process returns to S4 and continues to execute until the expected formation is obtained and the process navigates to the target area.

[0050] The present invention has the following beneficial effects:

[0051] When the number of clusters is large, the present invention uses the containment control protocol to effectively reduce the communication difficulty and computational complexity of the system, improve the control performance and robustness of the system, and meet the time constraints of position, speed and attitude for the three-dimensional trajectory tracking of under-actuated UUVs; multiple UUVs can maintain the desired formation and smoothly track the desired trajectory with good control performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0053] Figure 1 Schematic diagram of a flow chart of a containment control method based on a multi-UUV system according to an embodiment of the present invention;

[0054] Figure 2 This is a communication topology diagram proposed in an embodiment of the present invention, where 1-3 are second-level leaders, 4-7 are followers, and 8-9 are first-level leaders;

[0055] Figure 3 This is a diagram showing the change in the linear motion trajectory of a formation proposed in an embodiment of the present invention;

[0056] Figure 4 This is a diagram of longitudinal velocity changes during the linear motion of a formation proposed in an embodiment of the present invention;

[0057] Figure 5 This is a diagram of lateral velocity changes during the linear motion of a formation proposed in an embodiment of the present invention;

[0058] Figure 6 This is a diagram showing the change in heading angular velocity during the formation linear motion according to an embodiment of the present invention;

[0059] Figure 7 This is a diagram showing the variation of the formation linear motion error proposed in an embodiment of the present invention;

[0060] Figure 8This is a diagram showing the linear motion trajectory changes of a formation with interference proposed in an embodiment of the present invention;

[0061] Figure 9 A diagram showing changes in longitudinal velocity during linear motion of a formation with interference according to an embodiment of the present invention;

[0062] Figure 10 This is a diagram of lateral velocity changes during linear motion of a formation with interference proposed in an embodiment of the present invention;

[0063] Figure 11 This is a diagram showing the change in heading angular velocity during the linear motion of a formation with interference proposed in an embodiment of the present invention;

[0064] Figure 12 This is a diagram showing the linear motion error variation of a formation with interference proposed in an embodiment of the present invention. DETAILED DESCRIPTION

[0065] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0066] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0067] This paper, focusing on the communication characteristics of under-actuated multi-UUV systems and the computational complexity of their states, discloses a containment control method based on a multi-UUV system. The design of this containment control method for a multi-UUV (under-actuated) system has the following two reasons: (1) the under-actuated design can greatly simplify the UUV hardware system; (2) as the number of formation systems increases, the control cost and difficulty will gradually increase, which may result in the failure to achieve the mission objectives of the entire formation. In summary, the research on the containment control method for under-actuated multi-UUVs is not only of theoretical value, but also meets the actual control needs.

[0068] like Figure 1 As shown, this embodiment provides a containment control method based on a multi-UUV system, which specifically includes the following steps:

[0069] Step 1: Divide the underwater unmanned vehicle (UUV) cluster into a first-level leader, a second-level leader, and followers, establish the motion equation and dynamic equation of each UUV, and divide the first-level leader, the second-level leader, and followers according to their characteristics.

[0070] The mathematical model of underactuated UUV includes kinematic model and dynamic model, which are expressed as follows:

[0071] Kinematic model:

[0072]

[0073] Kinetic model:

[0074]

[0075] Among them, x, y, and z are the coordinates of the UUV in the rigid body coordinate system. x Axis, O y Axis, O z Axis position information, is the differential of the north coordinate, is the differential of the easting coordinate, is the differential of the depth coordinate, is the differential of the pitch angle, is the differential of the heading angle, θ is the trim angle, ψ is the heading angle, u is the longitudinal velocity, v is the transverse velocity, w is the velocity in the vertical direction of the deck, q is the trim angular velocity, r is the yaw angular velocity, is the differential of the longitudinal velocity, m is the weight of the UUV, Respectively represent the differentials of the external forces X, Y, N, M to the hull velocities u, v, r, u, I y For Y b The moment of inertia of the shaft, I z For Z b The moment of inertia of the axis, X u 、X u|u| 、Y v 、Y v|v| 、Z w 、Z w|w| 、M q 、M q|q| 、N r 、N r|r| is the hydrodynamic damping coefficient, X u 、Y v 、Z w 、M q 、N r Respectively represent the differentials of external forces X, Y, Z, M, N on the hull velocity u, v, w, q, r, X u|u| 、Y v|v| 、Z w|w| 、M q|q| 、N r|r| are the high-order terms after Taylor expansion, B is the buoyancy of UUV, is the longitudinal metacenter height, ω=[ω u ,ω v ,ω w ,ωq ,ω r ] T is the unknown bounded interference in the environment, τ u is the longitudinal thrust, t is the time, is the differential of the transverse velocity, is the differential of the velocity in the direction perpendicular to the deck, is the differential of the pitch angular velocity, T′=[T′1,0,0,T′2,T′3] T is the input delay caused by the longitudinal, pitch, and bow-up actuators in the rigid body coordinate system. This delay is an unknown bounded delay, τ q is the thrust in the direction of the pitch angle, is the differential of the heading angular velocity, τ r is the bow thrust.

[0076] Step 2: The UUV collects the navigator status information through the navigation equipment and sensors it carries, and initializes the current position information, attitude information, and speed information;

[0077] The nine UUVs in the formation are initially designated as primary leaders, three secondary leaders, and four followers. The nine UUVs surface, each acquiring its position, attitude, and speed information via BeiDou. The leader uses its sonar equipment to transmit its position, attitude, and speed to adjacent followers, and followers also transmit their attitude information to their adjacent UUVs using their sonar equipment. The nine UUVs descend to the same depth and begin depth-fixing navigation, with the leader transmitting its position, attitude, and speed information to adjacent UUVs.

[0078] Step 3: Introduce virtual reference points and design containment control protocols and inclusion control protocols;

[0079] The following formula is designed for the first-level navigator control protocol:

[0080]

[0081] Here right Set the following protocol:

[0082]

[0083] in, is the differential of the desired position, is the desired speed, x di is the desired horizontal position, y di is the expected longitudinal position, T is the transposition, is a real number, is the change in the desired lateral position, is the change in the desired longitudinal position, is the sum of some elements of the matrix, k c is a constant, k is a weight constant, j is the jth neighbor aircraft, a ij is the element in row i and column j in the adjacency matrix, are the expected value of its own estimation and the expected value of its neighbors, d j d i are the relative distance to itself and the relative distance to its neighbors, sgn(·) is the sign function, is the change in the relative distance of neighbors.

[0084] The secondary pilot control protocol can be further modified into the following formula:

[0085]

[0086] Where Γ is the pinning rate, k c is a constant, c is a constant, representing whether the current node spacecraft is restrained by the first-level navigator, i is the current spacecraft. Assume that N is the set of restrained nodes, is the set of non-pinned nodes, where Γ is designed as follows:

[0087]

[0088] Substituting Equation (5) into (3), we can verify the distributed protocol with the same level of navigator. In practice, the UUV is a rigid structure, which causes its combined velocity to be always greater than zero, and its value is bounded.

[0089] The follower control protocol is designed as follows:

[0090]

[0091] in, is the change in the expected position of the neighbor.

[0092] Current definition in in addition Substituting into formula (7) we get:

[0093]

[0094] Among them, A f =[a ij ],i,j∈{M+1,2,…,n},A l =[a ij], i∈{M+1, 2,…,n}, j∈{k+1,…,M}, D f =diag(d M+1 , d M+1 ,…,d n ).

[0095] To facilitate further analysis of the control protocol, further reasoning on formula (8) yields the inclusive control protocol:

[0096]

[0097] Among them, L f1 is the Laplace matrix between the first-level and second-level leaders, d f is the in-degree of the degree matrix, L f2 is the Laplace matrix between the two-level leaders, I2 is the identity matrix, p l is the position of the navigator, p f The position of the follower.

[0098] According to the above formula, when t→∞, the right half of the formula tends to zero exponentially as a whole, and all Laplace matrices exist. Then we can further deduce that when t→∞, That is, the goal of inclusive control formed by the secondary leader-follower group is achieved.

[0099] Step 4: Using the information from step 2 and the UUV model from step 1, design a dynamic path tracking controller and a kinematic path tracking controller to complete the path tracking of a single UUV.

[0100] Firstly, a trajectory tracking error equation considering the drift angle is constructed based on coordinate transformation. Then, based on the error equation, a kinematic controller based on the line of sight (LOS) method is designed. Finally, a dynamic controller is designed to enable the UUV to track the virtual target point.

[0101] (1) Longitudinal controller

[0102] The non-singular terminal sliding surface is designed as follows:

[0103]

[0104] Where c1 is a positive real number, p1 and q1 are both positive odd numbers, and 1<p1 / q1<2, u ei =u i -u di is the velocity tracking error, and the derivative of the sliding surface is obtained for:

[0105]

[0106] Substituting the UUV dynamic model into the equation, we can obtain:

[0107]

[0108] Speed ​​dynamics controller τ i1 , that is, the dynamic path tracking controller can be designed as:

[0109]

[0110] Among them, τ i1 is the longitudinal thrust, v i is the speed, r i is the heading angular velocity, u i is the longitudinal velocity, is the change in longitudinal velocity, is the expected change in longitudinal velocity, k1>0, u di is the expected speed, k1 is the weight, s i1 is the sliding surface, d 11 =-X u -X u|u| |u|.

[0111] (2) Heading angle controller

[0112] The same as above, the kinematic path tracking controller:

[0113]

[0114] Among them, τ i3 is the bow thrust, k2>0, Expected heading angular acceleration, The error between the heading angular velocity and the expected value, q2 is an odd number greater than zero, c2 is a constant greater than zero, p2 is an odd number greater than zero, k2 is the weight, s i2 is the sliding surface, d 33 =-N r -N r|r| |r|.

[0115] Step 5: Determine whether the desired formation is achieved. If the desired formation is formed, execute step 6. If not, return to step 4 to continue execution.

[0116] Step 6: Maintain formation and sail to the target area.

[0117] The UUV can track the desired trajectory quickly and smoothly with good control performance.

[0118] Simulation experiment verification and analysis

[0119] Consider a formation system consisting of 9 UUVs, where 2 UUVs are first-level leaders, 3 UUVs are second-level leaders, and the remaining 4 UUVs are followers. The communication topology between UUVs is as follows: Figure 2 As shown, it is clear that there is a directed spanning tree in the graph corresponding to the communication topology. According to the definition of the adjacency matrix mentioned in the previous graph theory foundation, it can be concluded that the adjacency matrix of the UUV cluster is expressed as:

[0120]

[0121] Assume that all UUVs have been stabilized in the z-axis direction, and that the UUVs move only on a two-dimensional horizontal plane. The hydrodynamic coefficient is m = 185, and I z =40,X u =-70, X u|u| =-100, Y v =-100, Y |v|v =-200, N r =-50, N |r|r =-100. The initial position state is η0 = [44.7, -75.3, -1.87] T , η1=[-1.6, -31.0, 2.06] T , η2=[-40.5,-93.8,-2.23] T , η3=[-22.4,8.9,2] T , η4=[-82.7, 34.6, -0.9] T , η5=[-13.6,-27.2,-1.34] T , η6=[-94.0,-37.3,-1.07] T , η7=[-100.0,-27.3,-1.07] T , η8=[30.0,-37.3,-2] T The desired path of the UUV formation is set as a straight line, which is divided into undisturbed and interfered.

[0122] like Figure 3 The following is the trajectory diagram of the UUV formation without interference, as shown in Figure 4 The figure shows the longitudinal velocity variation of the UUV formation in linear motion. Figure 5 The figure shows the lateral velocity variation of the UUV formation in linear motion; Figure 6 The figure shows the change of the angular velocity of the UUV formation in the straight line motion. Figure 7 The figure shows the variation of UUV formation motion error in linear motion. Figure 3-7It can be seen that the overall cluster control works well without interference.

[0123] External interference such as:

[0124]

[0125] Make a UUV formation simulation Figure 8 As shown in the figure, it is the trajectory diagram of the UUV formation under interference conditions, such as Figure 9 The figure shows the longitudinal velocity change of the UUV formation under interference. Figure 10 The figure shows the lateral velocity change of the UUV formation under interference. Figure 11 The figure shows the change of the UUV formation's bow angular velocity under interference. Figure 12 The figure shows the change of UUV formation motion error under interference. Figure 8-12 It can be seen that the overall cluster control effect remains good under interference conditions.

[0126] The above description is merely a preferred embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A containment control method based on a multi-UUV system, characterized in that: The specific steps include: S1. Obtain a cluster of underwater unmanned vehicles (UUVs) and construct kinematic and dynamic models for each UUV. The underwater unmanned vehicle (UUV) cluster includes a first-level leader, a second-level leader, and a follower; S2. Collecting the navigator status information of the UUV cluster and initializing it; S3. Setting a virtual reference point and designing a control protocol based on the UUV cluster, wherein the control protocol includes a containment control protocol and an inclusion control protocol; The containment control protocol includes a first-level leader control protocol, a second-level leader control protocol, and a follower control protocol; The first-level pilot control protocol is: here And right Set the following protocol: The secondary pilot control protocol is: The follower control protocol is: in, is the differential of the desired position, is the desired speed, x di is the desired horizontal position, y di is the expected longitudinal position, T is the transpose, R is a real number, is the change in the desired lateral position, is the change in the expected longitudinal position, Z is the sum of the matrix elements, k is the weight constant, j is the jth neighbor aircraft, a ij is the element in row i and column j in the adjacency matrix, are the expected value of its own estimation and the expected value of its neighbors, d j d i are the relative distance to itself and the relative distance to its neighbors, k c is a constant, sgn(·) is a sign function, is the change in the relative distance of neighbors, Γ is the containment rate, c is a constant, representing whether the current node spacecraft is restrained by the first-level navigator, i is the current spacecraft, and N is the set of restrained nodes. is the set of non-pinned nodes, is the change in the expected position of the neighbor; The inclusion control protocol is: Among them, L f1 is the Laplace matrix between the first-level and second-level leaders, d f is the in-degree of the degree matrix, L f2 is the Laplace matrix between the two-level leaders, I2 is the identity matrix, p l is the position of the navigator, p f for the follower's position; S4. Designing a path tracking controller using the navigator state information, the kinematic model, and the dynamic model; S5. Complete the path tracking of a single UUV according to the control protocol and the path tracking controller, obtain the desired formation and maintain the formation to navigate to the target area, and realize the containment control based on the multi-UUV system.

2. The containment control method based on a multi-UUV system according to claim 1, characterized in that: The kinematic model is: The kinetic model is: in, is the differential of the north coordinate, u is the longitudinal velocity, ψ is the heading angle, θ is the pitch angle, v is the lateral velocity, is the differential of the easting coordinate, is the differential of the depth coordinate, is the differential of the pitch angle, q is the pitch angular velocity, is the differential of the heading angle, r is the yaw angular velocity, is the differential of the longitudinal velocity, m is the weight of the UUV, Respectively represent the differentials of the external forces X, Y, and N on the hull velocities u, v, and r, w is the velocity in the direction perpendicular to the deck, τ u is the longitudinal thrust, t is the time, T'=[T'1,0,0,T'2,T'3] T is the unknown bounded time delay of the input of the longitudinal, pitch and bow actuators in the rigid coordinate system, ω=[ω u ,ω v ,ω w ,ω q ,ω r ] T For unknown bounded interference in the environment, is the differential of the transverse velocity, is the differential of the velocity in the direction perpendicular to the deck, is the differential of the pitch angular velocity, I y For Y b The moment of inertia of the shaft, represents the differential of the external force M to the hull velocity u, B is the buoyancy of the UUV, is the longitudinal metacenter height, τ q is the thrust in the direction of the pitch angle, is the differential of the heading angular velocity, I z For Z b Moment of inertia of the shaft, τ r is the bow thrust, X u 、X u|u| 、Y v 、Y v|v| 、Z w 、Z w|w| 、M q 、M q|q| 、N r 、N r|r| is the hydrodynamic damping coefficient.

3. The containment control method based on a multi-UUV system according to claim 1, characterized in that: Navigator status information includes position information, attitude information and speed information.

4. The containment control method based on a multi-UUV system according to claim 2, characterized in that: Designing the path tracking controller using the pilot state information and the kinematic model and the dynamic model includes: According to the pilot state information, a non-singular terminal sliding surface is designed and obtained. The sliding surface is: Through the sliding surface, the derivative of the sliding surface is obtained as: Importing the dynamic model and the kinematic model into the derivatives of the sliding surface respectively to obtain the path tracking controller; The path tracking controller is: The path tracking controller includes a dynamic path tracking controller and a kinematic path tracking controller; Among them, s i1 is the sliding surface, u ei is the speed tracking error, c1 is a positive real number, p1 and q1 are both positive odd numbers, and 1 <p1 / q1<2, is the derivative of the sliding surface, is the change in longitudinal velocity, Expected change in longitudinal velocity, v i is the speed, r i is the heading angular velocity, d 11 =-X u -X u|u| |u|,X u represents the differential of the external force X to the hull velocity u, X u|u| is the higher-order term after Taylor expansion, u i is the longitudinal velocity, τ i1 For longitudinal thrust.

5. The containment control method based on a multi-UUV system according to claim 4, characterized in that: The dynamic path tracking controller is: Among them, k1 is the weight.

6. The containment control method based on a multi-UUV system according to claim 5, characterized in that: The kinematic path tracking controller is: Among them, τ i3 is the bow thrust, d 33 =-N r -N r|r| |r|,N r Represents the differential of the external force N to the hull velocity r, N r|r| is the higher-order term after Taylor expansion, is the desired heading angular acceleration, q2 is an odd number greater than zero, c2 is a constant greater than zero, p2 is an odd number greater than zero, is the error between the heading angular velocity and the expected value, k2 is the weight, s i2 is the sliding surface.

7. The containment control method based on a multi-UUV system according to claim 1, characterized in that: Completing the path tracking of a single UUV according to the control protocol and the path tracking controller, obtaining the desired formation and maintaining the formation to navigate to the target area includes: Complete path tracking of a single UUV according to the control protocol and the path tracking controller to obtain a formation result; determining whether the formation result satisfies an expected formation, and if the formation result satisfies the expected formation, continuing to maintain the formation result until the formation reaches a target area; When the formation result does not form the expected formation, the process returns to S4 and continues to execute until the expected formation is obtained and the process navigates to the target area.

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