Double-pod propelling intelligent ship path tracking controller under disturbance of time-varying marine environment

Abstract

The invention provides a double-pod propulsion intelligent ship path tracking controller under time-varying marine environment disturbance. The controller comprises a sideslip angle estimation module; the sideslip angle estimation module receives position, course and resultant velocity signals from the double-pod propelled intelligent ship, and sends a sideslip angle estimation value signal to the path tracking course guidance law module; the path tracking course guidance law module receives a sideslip angle estimation value signal from the sideslip angle estimation module, receives a position signal from the double-pod propelled intelligent ship, and sends a course guidance signal to the anti-interference control law module; according to the invention, under the disturbance of the time-varying complex marine environment, the double-pod intelligent ship can be ensured to realize accurate control of dynamics and accurate tracking of an expected path.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent ships, in particular, especially relates to a path tracking controller of a double-screw propeller intelligent ship under time-varying ocean environment disturbance. BACKGROUND

[0002] As an emerging development field of the shipping industry, intelligent ships provide a safe, efficient, and sustainable transformative solution for modern shipping, which is highly valued by the global shipping industry and the technology industry. Intelligent ships can achieve highly automated and intelligent operations, including automatic navigation, autonomous collision avoidance, automatic detection, autonomous berthing, and autonomous maintenance, through the integration of advanced navigation systems, automatic control technology, and machine learning algorithms. Among them, double-screw propeller intelligent ships can provide flexible power and direction control and have better maneuverability compared to traditional paddle rudder ships due to their unique propulsion and steering characteristics. However, the complexity of their actuators poses greater challenges to the design of navigation control algorithms.

[0003] Intelligent ship path tracking control requires the intelligent ship to track a geometric path that is decoupled from time, which is used for tasks such as narrow channel navigation, autonomous berthing, and other tasks that do not have strict time requirements. Intelligent ships will inevitably be affected by time-varying ocean environment disturbances in actual ocean environments. If disturbances are not reasonably handled when designing path tracking algorithms, it will greatly affect the accuracy of intelligent ship path tracking. Therefore, to adapt to the dynamic changes and uncertainties of the ocean environment, it is of great practical significance to study the path tracking control method of double-screw propeller intelligent ships under time-varying ocean environment disturbance.

[0004] The existing intelligent ship path tracking control method still has the following shortcomings:

[0005] First, the existing side slip compensation method in intelligent ship path tracking control mostly compensates the side slip angle in the saturation arctangent function. However, in actual navigation, due to the influence of external time-varying disturbances such as wind, waves, and currents, the intelligent ship will produce rapidly changing side slip angles, which may lead to insufficient side slip angle compensation and thus adversely affect the path tracking performance.

[0006] Second, the existing intelligent ship path tracking control is mostly designed with thrust and torque as control inputs, but in practice, the motion of the intelligent ship is adjusted by propellers and rudders or pod propellers. Without power distribution, the thrust and torque generated by the controller cannot be directly input as control instructions to the actuator.

[0007] Third, in the existing intelligent ship anti-interference control method, the extended state observer is based on a certain fixed frequency to estimate the disturbance. This design will amplify the high-frequency measurement noise at high bandwidth, and the low bandwidth will weaken the disturbance suppression performance. These defects limit the estimation performance of the disturbance in the complex dynamic environment. SUMMARY

[0008] To solve the problems in the prior art, the application provides a double-slung pod propulsion intelligent ship path tracking controller under time-varying marine environment disturbance, which can guarantee the dynamic precise control and precise tracking of the expected path of the double-slung pod intelligent ship under time-varying complex marine environment disturbance.

[0009] The technical means adopted by the application are as follows:

[0010] A double-slung pod propulsion intelligent ship path tracking controller under time-varying marine environment disturbance comprises:

[0011] A sideslip angle estimation module, which receives position, heading, and combined speed signals from the double-slung pod propulsion intelligent ship, and sends a sideslip angle estimation value signal to a path tracking heading guidance law module;

[0012] A path tracking heading guidance law module, which receives the sideslip angle estimation value signal from the sideslip angle estimation module, receives the position signal from the double-slung pod propulsion intelligent ship, and sends a signal to an anti-interference control law module;

[0013] An anti-interference control law module, which receives the heading guidance signal from the path tracking heading guidance law module, receives the disturbance observation value signal from a parallel extended state observer module, and sends a slung pod rotation angle signal to the double-slung pod propulsion intelligent ship;

[0014] A parallel extended state observer module, which receives the angular velocity signal from the slung pod propulsion intelligent ship, and sends the disturbance observation value signal to the anti-interference control law module.

[0015] Further, the kinematic model of the double-slung pod propulsion intelligent ship is:

[0016]

[0017] In the formula, p = [x, y] T ∈R 2is the position of the twin-propeller propulsion intelligent ship in the earth coordinate system; ψ is the heading angle; u represents the surge velocity in the body coordinate system; v represents the sway velocity in the body coordinate system; and r represents the yaw angular velocity in the body coordinate system;

[0018]

[0019] wherein m is the mass of the intelligent ship; m x is the added mass of the intelligent ship in the surge direction; m y is the added mass of the intelligent ship in the sway direction; I zz is the moment of inertia of the intelligent ship; J zz is the added moment of inertia of the intelligent ship; H represents the damping; P represents the propeller; R represents the rudder; and D represents the disturbance.

[0020] Further, the design method of the sideslip angle estimation module is as follows:

[0021] The scenario of the intelligent ship tracking a path composed of multiple path points is studied; in the earth coordinate system, the path is defined by two path points p k = [x k , y k ] T and p k+1 = [x k+1 , y k+1 ] T The path tangent angle is calculated by the following formula:

[0022] ψ d = atan2 (y k+1 - y k , x k+1 - x k )

[0023] For the intelligent ship located at (x, y), the longitudinal error x e and the lateral error y e of the path tracking, i.e., the tracking error formula, are defined as follows:

[0024]

[0025] Based on the formula of the kinematic model of the twin-propeller propulsion intelligent ship, the time derivative of the tracking error formula is derived as follows:

[0026]

[0027] wherein β = atan2 (v, u) is the sideslip angle; cos β ≈ 1 and sin β ≈ β; and U is the ship resultant velocity;

[0028] The derivative of the lateral tracking error in the time derivative of the tracking error formula is as follows:

[0029]

[0030] where φ = Ucos(ψ - ψ d )β;

[0031] The extended state observer is designed as follows:

[0032]

[0033] where y is the estimation of y e , and k1 and k2 are observer gains;

[0034] Ucos(ψ - ψ d ) is a known quantity, and the estimation of side slip angle is as follows:

[0035]

[0036] Further, the design method of the path tracking heading guidance law module is as follows:

[0037] Based on the principle of line-of-sight guidance, the path tracking heading guidance law of the intelligent ship is designed as follows:

[0038]

[0039] where Δ is the look-ahead distance;

[0040] When the intelligent ship enters the specified range of the current target waypoint p k , the intelligent ship switches from tracking the target path p k-1 p k to tracking the target path p k p k+1 , with the current target waypoint p k as the center and R as the turning radius; the switching criterion is expressed as:

[0041]

[0042] Further, the design method of the parallel extended state observer module is as follows:

[0043] In the yaw direction, the angular velocity of the intelligent ship is controlled by adjusting the pod rotation angle δ of the propeller; according to Taylor series, sin(δ) is expanded as:

[0044]

[0045] The dynamic formula in the yaw direction is:

[0046]

[0047] wherein,

[0048] Designing a parallel expanding state observer for sigma r Real-time estimation is performed, and the formula is as follows:

[0049]

[0050] wherein, the augmented state is the estimated state r 0rj at the frequency ω j ; the observer gain is selected as is a positive observer gain; the state and the estimated total disturbance are

[0051] Further, the anti-interference control law of the anti-interference control law module is as follows:

[0052]

[0053] wherein, k δ , k ψ , k r are positive gain parameters.

[0054] The application also provides a storage medium, which comprises a stored program, wherein the program performs the path tracking controller of the double-suspension-propeller intelligent ship under time-varying marine environmental disturbance when running.

[0055] The application also provides an electronic device, which comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, and the processor performs the path tracking controller of the double-suspension-propeller intelligent ship under time-varying marine environmental disturbance through the computer program.

[0056] Compared with the prior art, the application has the following advantages:

[0057] Firstly, unlike the existing intelligent ship path tracking control method which uses a saturated inverse tangent function to compensate the sideslip angle, the application uses an expanding state observer to estimate the sideslip angle in real time according to the influence of environmental disturbance on the tracking control when the double-suspension-propeller intelligent ship moves, and directly compensates in the heading guidance law, thereby guaranteeing the tracking performance when the sideslip angle changes rapidly.

[0058] Second, unlike existing control methods that rely on ship models that struggle to accurately capture intelligent ship dynamics or analyze local changes and interactions between the hull and actuators, this paper designs an anti-interference path-tracking control method for twin-pod propulsion intelligent ships based on the MMG model. By using propeller speed and pod angle as the system's control inputs, it effectively bridges the gap between theoretical simulations and actual offshore operations.

[0059] Third, unlike the extended state observer designed based on a single frequency estimation in existing anti-interference control methods, the present invention proposes a parallel extended state observer. Under a parallel structure, multiple extended state observers simultaneously estimate disturbances at different frequencies, which has better anti-interference ability and estimation accuracy than traditional extended state observers. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0061] Figure 1 It is a schematic diagram of the controller structure of the present invention.

[0062] Figure 2 It is a force and moment curve diagram of wind disturbance of the present invention.

[0063] Figure 3 This is a navigation trajectory diagram of an intelligent ship according to the present invention.

[0064] Figure 4 It is an estimation effect diagram of the sideslip angle and lateral tracking error of the present invention.

[0065] Figure 5 It is a curve diagram of the rotation angle change of the pod of the present invention.

[0066] Figure 6 This is a diagram showing the angular velocity and heading tracking effects of the intelligent ship of the present invention.

[0067] Figure 7 This is a disturbance observation effect diagram of the parallel extended state observer of the present invention. DETAILED DESCRIPTION

[0068] In order to better understand the technical scheme of the present application, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present application.

[0069] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above-described accompanying drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units need not be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0070] As shown in Figure 1 The present application provides a path tracking controller for a twin- pod propulsion intelligent ship under time-varying ocean environment disturbance, comprising:

[0071] a sideslip angle estimation module; the sideslip angle estimation module receives position, heading, and combined speed signals from the twin-pod propulsion intelligent ship, and sends a sideslip angle estimation value signal to the path tracking heading guidance law module;

[0072] a path tracking heading guidance law module; the path tracking heading guidance law module receives a sideslip angle estimation value signal from the sideslip angle estimation module, and receives a position signal from the twin-pod propulsion intelligent ship, and sends a heading guidance signal to the anti-interference control law module;

[0073] an anti-interference control law module; the anti-interference control law module receives a heading guidance signal from the path tracking heading guidance law module, and receives a disturbance observation value signal from the parallel extended state observer module, and sends a pod rotation angle signal to the twin-pod propulsion intelligent ship;

[0074] a parallel extended state observer module; the parallel extended state observer module receives an angular velocity signal from the twin-pod propulsion intelligent ship, and sends a disturbance observation value signal to the anti-interference control law module.

[0075] The kinematics model of the double-gondola intelligent ship can be described as:

[0076]

[0077] In the formula, p = [x, y] T ∈R 2 is the position of the intelligent ship in the earth coordinate system; ψ is the heading angle; u, v, and r respectively represent the surge velocity, sway velocity, and yaw angular velocity in the ship coordinate system.

[0078] The dynamics model of the double-gondola intelligent ship is:

[0079]

[0080] In the formula, m, m x , m y , I zz , and J zz are respectively the mass of the intelligent ship, the added mass in the surge direction, the added mass in the sway direction, the moment of inertia, and the added moment of inertia; the subscripts H, P, R, and D respectively represent the damping, the propeller, the rudder, and the disturbance.

[0081] (1) Ship viscous hydrodynamic force and moment calculation:

[0082] The viscous hydrodynamic force and moment acting on the ship are as follows:

[0083]

[0084] In the formula, ρ is the water density, L is the ship length, d is the ship draft, is the ship resultant velocity.

[0085] The dimensionless force and moment are modeled as follows:

[0086]

[0087] In the formula, X(u) is the straight-ahead resistance coefficient, X′ (·) , Y′ (·) , and N′ (·) are the dimensionless hydrodynamic derivatives.

[0088] (2) Propeller thrust calculation:

[0089] When the ship is in autonomous navigation mode, the double-gondola propulsion system operates synchronously, that is, δ L = δ R = δ. Then, the force and moment generated thereby are as follows:

[0090]

[0091] where t p is the thrust reduction factor, n is the rotation speed of a single propeller, D P is the diameter of the propeller, l x is the longitudinal coordinate of the pod, the thrust coefficient K T (J P ) is defined as follows:

[0092]

[0093] where a0, a1, a2 are constants. P can be expressed as

[0094]

[0095] where w P is the wake factor at the position of the propeller.

[0096] (3) Calculation of the hydrodynamic force and moment of the double-pod:

[0097] The pod produces a force and moment similar to a rudder during the ship's turning process, which can be expressed as follows:

[0098]

[0099] where F N is the normal force, t R is the pod resistance reduction factor, a H is the pod correction factor, x R is the transverse coordinate of the pod force action point in the ship coordinate system.

[0100] In the present application, the simplified form of the pod force and moment is used, which is expressed as follows

[0101]

[0102] where K p and K q are the hydrodynamic derivatives of the pod.

[0103] Substituting equations (5) and (8) into equation (2), the dynamic model of the double-pod intelligent ship in the yaw direction can be written as

[0104]

[0105] The design method comprises the following steps:

[0106] A. Side slip angle estimation

[0107] In the application, the scenario of an intelligent ship tracking a path composed of multiple path points is studied. Considering in the earth coordinate system, by two path points p k=[x k ,y k ] T and p k+1 =[x k+1 ,y k+1 ] T If the straight line segment is defined, the path tangent angle can be calculated as follows:

[0108] ψ d =atan2(y k+1 -y k ,x k+1 -x k ) (11)

[0109] For the smart ship located at (x, y), the longitudinal error x of path tracking is e and lateral error y e The definition is as follows:

[0110]

[0111] Based on the kinematic formula (1), the time derivative of the tracking error formula (12) can be derived as:

[0112]

[0113] Where β = atan2(v,u) is the sideslip angle.

[0114] The sideslip angle is usually small, so cosβ≈1, sinβ≈β. Therefore, the derivative of the lateral tracking error in equation (13) can be expressed as follows:

[0115]

[0116] Where φ=Ucos(ψ-ψ d )β.

[0117] Based on formula (14), with φ as the quantity to be estimated, the extended state observer is designed as follows:

[0118]

[0119] In the formula y e The estimated value of , k1 and k2 are the observer gains. Since Ucos(ψ-ψ d ) is a known quantity, and the estimated value of the sideslip angle can be obtained by the following formula

[0120]

[0121] B. Path-following heading guidance law design

[0122] The line-of-sight guidance method is a guidance method that simulates the behavior of a helmsman maneuvering a ship. Based on the line-of-sight guidance principle, the path-tracking heading guidance law for intelligent ships is designed as follows:

[0123]

[0124] Where Δ is the foresight distance. In formula (17), the estimated value of the sideslip angle is introduced to directly correct the desired heading.

[0125] When the smart ship enters the current target waypoint p k When the target path is within a certain range, the algorithm will make a judgment and make the smart ship change from tracking the target path p k-1 p k Switch to tracking target path p k p k+1 . With the current target waypoint p k is the center of the circle, and R is the turning radius. The switching criterion can be expressed as:

[0126]

[0127] C. Parallel Extended State Observer Design

[0128] In the bowing direction, the angular velocity of the smart ship is controlled by adjusting the propeller pod rotation angle δ. According to the Taylor series, sin(δ) can be expanded as:

[0129]

[0130] Therefore, the dynamic formula in the bowing direction can be written as:

[0131]

[0132] In the formula

[0133] Design a parallel extended state observer for σ r Perform real-time estimation as follows:

[0134]

[0135] In the formula, the augmented state is at frequency ω 0rj The estimated state r j The observer gain is selected as is a positive observer gain. And the estimated total disturbance is

[0136] D. Anti-interference control law design

[0137] The anti-interference control law is designed as follows:

[0138]

[0139] In the formula, k δ , k ψ , k r are positive constants, and the subscripts respectively represent the nacelle rotation angle, the heading, and the angular velocity.

[0140] Embodiment

[0141] The following further describes the application by taking the new Hongqi intelligent ship of the Dalian Maritime University as a simulation ship. Figure 1 The structure diagram of the path tracking controller of the double-nacelle propulsion intelligent ship under the time-varying ocean environment disturbance designed by the application.

[0142] The kinematic model and the dynamic model of the double-nacelle propulsion intelligent ship are as follows:

[0143]

[0144]

[0145] X H , X P , X R , X D The calculation is the same as described in the above formula, and the propeller speed n = 4.

[0146] The research of the application considers the influence of the time-varying environment disturbance, and the main focus is the influence of the wind disturbance. In the navigation process, the wind disturbance has a significant influence on the intelligent ship and the motion control performance. The wind disturbance model used in the present example is as follows:

[0147]

[0148] In the formula, X w , Y w , and N w respectively represent the longitudinal force, the lateral force, and the yaw moment generated by the wind, ρ a is the air density, A f and A s respectively represent the windward surface and the side surface projection area of the intelligent ship above the waterline, L oa is the length of the whole intelligent ship, U w and α w respectively represent the relative wind speed and the wind direction angle, U w and α w are modeled as a first-order Gauss-Markov process:

[0149]

[0150] where w u and w ψ are Gaussian white noise, and μ≥0 is a constant.

[0151] The wind pressure coefficients in the x and y axis directions and the wind pressure moment coefficient about the z axis are represented by variables C wx (α w ), C wy (α w ), and C wn (α w ), respectively:

[0152]

[0153] where c x ∈ {0.50, 0.90}, c y ∈ {0.70, 0.95}, and c n ∈ {0.05, 0.20}.

[0154] The specific wind disturbance model parameters are as follows:

[0155] ρ a = 1.224, A f = 300, A s = 900, and L oa = 100

[0156] μ = 0, c x = 0.7, c y = 0.8, and c n = 0.1

[0157] The controller used in this example satisfies the controller structure described by Equations (19)-(22), and the specific controller parameters are as follows:

[0158] M = 3, ω 0r1 = 10 / 9, ω 0r2 = 10 / 3, and ω 0r1 = 10

[0159] k δ = (30*π) / 180, k ψ = 0.2, and k r = 0.179

[0160] The path points are set as follows:

[0161] p1 = (-400, -400), p2 = (-400, 400), p3 = (600, 700),

[0162] p4 = (1000, 1400), p5 = (2000, 1400), p6 = (2400, 800)

[0163] The simulation parameters of the path following course guidance law are as follows:

[0164] k1 = 20 and k2 = 100 are observer gains, Δ = 3*L, and L = 69.833 is the look-ahead distance.

[0165] The simulation results are shown in Figures 2-6 . Figure 2 is the force and moment of the wind disturbance when the intelligent ship is sailing. Figure 3 is the intelligent ship sailing trajectory, the thin dotted line in the figure is the given desired course, and the solid line is the actual sailing trajectory of the intelligent ship. As can be seen from the figure, the intelligent ship still stably tracks the given desired course under the disturbance of the wind. Figure 4 is the estimation effect of the sideslip angle and lateral tracking error, the solid line in the figure represents the actual sideslip angle and lateral tracking error, and the dashed line represents the observed sideslip angle and lateral tracking error. It can be seen that the observer has good observation effect on the sideslip angle and lateral tracking error. Figure 5 is the change curve of the pod rotation angle of the intelligent ship, and it can be seen from the figure that the pod rotation angle of the intelligent ship is maintained within the set range. Figure 6 is the angular velocity and heading tracking effect of the intelligent ship, and it can be seen that the angular velocity curve is relatively smooth, and the turning control of the ship is relatively stable without sharp fluctuations. The actual heading curve changes synchronously with the target heading curve, has high tracking accuracy, and the heading curve is relatively smooth, indicating that the controller has good dynamic performance. Figure 7 is the disturbance observation effect of the parallel extended state observer, and the solid line in the figure represents the actual disturbance, and the dashed line represents the observed disturbance. It can be seen that the observer has good observation effect on the uncertainty and disturbance.

[0166] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A path tracking controller for a dual-pod propulsion intelligent ship under time-varying ocean environment disturbances, characterized in that: include: Sideslip angle estimation module; The sideslip angle estimation module receives position, heading, and total speed signals from the dual-pod propulsion intelligent ship, and sends a sideslip angle estimation value signal to the path tracking and heading guidance law module; A path tracking and heading guidance law module; the path tracking and heading guidance law module receives a sideslip angle estimation value signal from the sideslip angle estimation module, the path tracking and heading guidance law module receives a position signal from the dual-pod propulsion intelligent ship, and the path tracking and heading guidance law module sends a heading guidance signal to the anti-interference control law module; an anti-interference control law module; the anti-interference control law module receives a heading guidance signal from a path tracking heading guidance law module, the anti-interference control law module receives a disturbance observation value signal from a parallel extended state observer module, and the anti-interference control law module sends a pod rotation angle signal to the dual-pod propulsion intelligent ship; A parallel extended state observer module; the parallel extended state observer module receives an angular velocity signal from a pod-propelled intelligent ship, and the parallel extended state observer module sends a disturbance observation value signal to an anti-interference control law module.

2. The dual-pod propulsion intelligent ship path tracking controller under time-varying ocean environment disturbance according to claim 1 is characterized in that: The kinematic model of the dual-pod propulsion intelligent ship is: Where p = [x, y] T ∈R 2 is the position of the twin-pod propulsion intelligent ship in the earth coordinate system; ψ is the heading angle; u represents the longitudinal velocity in the hull coordinate system; v represents the transverse velocity in the hull coordinate system; r represents the bow angular velocity in the hull coordinate system; Where, m is the mass of the smart ship; m x is the additional mass of the intelligent ship in the longitudinal direction; m y I is the additional mass of the intelligent ship in the swaying direction; zz is the rotational inertia of the intelligent ship; J zz The additional moment of inertia for the smart ship; H represents damping; P represents propeller; R represents rudder; and D represents disturbance.

3. The dual-pod propulsion intelligent ship path tracking controller under time-varying ocean environment disturbance according to claim 1 is characterized in that: The design method of the sideslip angle estimation module is as follows: The scenario of an intelligent ship tracking a path consisting of multiple path points is studied. Consider a path consisting of two path points p in the earth coordinate system. k =[x k ,y k ] T and p k+1 =[x k+1 ,y k+1 ] T For a defined straight line segment, the path tangent angle is calculated using the following formula: ψ d =atan2(y k+1 -y k ,x k+1 -x k ) For the smart ship located at (x, y), the longitudinal error x of path tracking is e and lateral error y e That is, the tracking error is defined as follows: Based on the formula of the kinematic model of the dual-pod propulsion intelligent ship, the time derivative of the tracking error is derived as: Where, β = atan2(v,u) is the sideslip angle; cosβ≈1, sinβ≈β; U is the total speed of the ship; The derivative of the lateral tracking error in the time derivative of the tracking error formula is as follows: In the formula, φ = Ucos(ψ-ψ d )b; Taking φ as the quantity to be estimated, the extended state observer is designed as follows: Where, y e The estimated value of , k1 and k2 are the observer gains; Ucos(ψ-ψ d ) is a known quantity, and the estimated value of the sideslip angle is as follows:

4. The dual-pod propulsion intelligent ship path tracking controller under time-varying ocean environment disturbance according to claim 1 is characterized in that: The design method of the path tracking heading guidance law module is as follows: Based on the line-of-sight guidance principle, the path tracking and heading guidance law of the intelligent ship is designed as follows: Where Δ is the foresight distance; When the smart ship enters the current target waypoint p k When the smart ship tracks the target path p k-1 p k Switch to tracking target path p k p k+1 ; Take the current target waypoint p k is the center of the circle, R is the turning radius; the switching criterion is expressed as:

5. The dual-pod propulsion intelligent ship path tracking controller under time-varying ocean environment disturbance according to claim 1 is characterized in that: The design method of the parallel extended state observer module is as follows: In the bowing direction, the angular velocity of the smart ship is controlled by adjusting the propeller pod rotation angle δ. According to the Taylor series, sin(δ) is expanded as: The dynamic formula in the bowing direction is: Where, Design a parallel extended state observer for σ r For real-time estimation, the formula is as follows: In the formula, the augmented state is at frequency ω 0rj The estimated state r j ; The observer gain is selected as is a positive observer gain; the state And the estimated total disturbance is 6. The dual-pod propulsion intelligent ship path tracking controller under time-varying ocean environment disturbance according to claim 1 is characterized in that: The anti-interference control law of the anti-interference control law module is as follows: Where k δ 、k ψ 、k r is a positive gain parameter.

7. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is run, the dual-pod propulsion intelligent ship path tracking controller under time-varying marine environment disturbance described in any one of claims 1 to 6 is executed.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: The processor executes the dual-pod propulsion intelligent ship path tracking controller under time-varying marine environment disturbances as described in any one of claims 1 to 6 through the computer program.

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