Multi-tugboat cooperative berthing controller under complex multiple constraints

Abstract

The invention provides a multi-tugboat collaborative berthing controller under complex multiple constraints. The multi-tugboat collaborative berthing controller comprises a finite time kinematics module, an instruction optimization module and a finite time dynamics module. The finite time kinematics module receives position and course information and expected position and course information of a target tugboat in the finite time kinematics module, and the finite time kinematics module outputs expected speed to the instruction optimization module; the instruction optimization module is used for receiving an expected speed from the finite time kinematics module and position and course information of a target tugboat from the finite time dynamics module; the instruction optimization module generates an optimized speed signal according to the contact force constraint between tugboats and ships, the speed constraint of the tugboats and the ship dynamic constraint and outputs the optimized speed signal to the finite time dynamics module; according to the method, the calculation pressure is greatly reduced, and the resource consumption is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-tugboat collaborative berthing, and more particularly, to a multi-tugboat collaborative berthing controller under complex multi-constraints. Background Art

[0002] With the continuous growth of port operation volume, the demand for large ships to berth and depart has been rising continuously, which has promoted the development of multi-tugboat collaborative berthing technology. The berthing and departing problem of large ships in a complex port environment is the basis for realizing various complex control tasks of ships. However, the complexity of the port waters, the combined interference in the offshore environment, and the increase in ship size have all put more stringent requirements on tugboat collaborative control technology. Currently, multi-tugboat collaborative berthing is mostly completed by manually operating tugboats. The existing collaborative berthing technology far from meets the berthing needs of large ships. Therefore, there is an urgent need to study a new type of multi-tugboat collaborative berthing method that minimizes or completely avoids manual monitoring.

[0003] The existing multi-tugboat collaborative berthing methods have the following problems:

[0004] First, when the collaborative berthing algorithm processes heavy real-time data tasks, it must make decisions quickly and accurately to ensure the safe and efficient berthing of the ship. However, due to the need for prediction iteration, the traditional model predictive control method often requires huge computational resource support, which undoubtedly becomes a huge obstacle to real-time response in the case of limited resources.

[0005] Second, one of the ways to achieve collaborative berthing is to use tow ropes connected to the ship for assistance. However, due to improper operation of the tow ropes by the operator, such as too fast cable release speed, too fast tugboat speed when starting to tow, etc., it may cause excessive force on the tow rope and pose safety problems.

[0006] Third, the existing collaborative berthing methods rarely consider multiple physical constraint limitations and external environmental disturbance effects in a complex port environment at the same time, which may lead to a decline in the performance of the collaborative berthing system or even abnormal operation. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to propose a multi-tugboat collaborative berthing controller under complex multi-constraints to solve the technical problem that the existing multi-tugboat collaborative berthing methods cannot respond in real time under limited resources.

[0008] The technical means adopted by the present invention are as follows:

[0009] A multi-tugboat collaborative berthing controller under complex multi-constraints, characterized in that it includes a finite-time kinematics module, an instruction optimization module, and a finite-time dynamics module;

[0010] The finite-time kinematics module receives the position and heading information ζ1, ζ2 of the target tugboat in the finite-time dynamics module and the desired position and heading information ζ 1d , ζ 2d . The finite-time kinematics module outputs the desired velocity μ 1hc , μ 2hc to the command optimization module;

[0011] The command optimization module receives the desired velocity μ 1hc , μ 2hc from the finite-time kinematics module and the position and heading information ζ1, ζ2 of the target tugboat in the finite-time dynamics module. The command optimization module generates an optimized velocity signal μ 1ho , μ 2ho based on the contact force constraint between the tugboat and the ship, the velocity constraint of the tugboat, and the ship dynamics constraint, and outputs it to the finite-time dynamics module;

[0012] The finite-time dynamics module includes a dynamics controller, an extended state observer based on a robust differentiator, and a target tugboat. The dynamics controller receives the velocity signal μ 1ho , μ 2ho from the command optimization module, the disturbance estimator of the extended state observer based on the robust differentiator, and the current velocity information from the target tugboat. The dynamics controller outputs the tugboat torque to the extended state observer based on the robust differentiator and the target tugboat. The target tugboat receives the tugboat torque and outputs the current velocity information to the dynamics controller and the extended state observer based on the robust differentiator.

[0013] Furthermore, the mathematical model of the target tugboat includes a kinematic model and a dynamic model, and the expressions are as follows:

[0014]

[0015] where is the position of the i-th tugboat in the earth coordinate system, χ i is the yaw angle of the i-th tugboat, i ∈ {1, 2}; are the surge velocity, sway velocity, and yaw angular velocity vectors in the carried hull coordinate system, respectively; is the inertia matrix; and represent the Coriolis centripetal matrix and the damping matrix, respectively; is the control input vector; represents the environmental disturbance vector;

[0016] is the rotation matrix, expressed as:

[0017]

[0018] Rewrite the kinematic model and the dynamic model in the Earth coordinate system as follows:

[0019]

[0020] Where, represent the velocity vector, the control input vector, and the superimposed disturbance vector in the Earth coordinate system, respectively.

[0021] Furthermore, the establishment steps of the finite-time kinematic module are as follows:

[0022] Assume that the ship to be towed enters the port and finally parallels the port shoreline. The port shoreline is as follows:

[0023] i b = e b a + f b b + g b

[0024] Where, e b , f b and g b are constants;

[0025] When the ship to be towed completes berthing, the direction of the tugboat is perpendicular to the port shoreline. The desired yaw angle χ id of the tugboat is as follows:

[0026]

[0027] Where, χ s = atan2(-e b / f b ) is the angle of the port shoreline. ζ s is designed using χ

[0028] ζ 1d = [a 1d , b 1d , χ 1d T and χ 2d = [a 1d + dcos(χ s ), b 1d + dsin(χ s ), χ 2d T ;

[0029] To complete the multi-tugboat collaborative berthing task, the tracking errors w i1 = [c i1 , h​​i2 , χ i3 T Written as:

[0030] w i1 = χ i -χ id

[0031] A finite-time speed controller is designed in the Earth coordinate system, i.e.:

[0032]

[0033] where P i1 = diag{j iu1 , j iv2 , j ir3} is a control gain matrix.

[0034] Furthermore, the steps for establishing the finite-time dynamics module are as follows:

[0035] Design an observer as follows based on the extended state observer with a robust differentiator:

[0036]

[0037] where is the estimated speed error, P io1 = diag{j io1 , j io2 , j io3} and P io2 = diag{j io4 , j io5 , j io6} are observer gain matrices;

[0038] Define and Using the kinematic model and dynamic model in the Earth coordinate system, the error dynamics of the extended state observer with a robust differentiator are:

[0039]

[0040] According to the super-twisting control technique, the calculation formula for the dynamic sliding surface is c i = [c i1 , c i2 , c i3 T = μ ih -μ iho , and its time derivative is:

[0041]

[0042] ​​Design the finite-time dynamics module in the Earth coordinate system:

[0043]

[0044] Among them, P id1 = diag{j id1 , j id2 , j id3} and P id2 = diag{j id4 , j id5 , j id6} are control gain matrices.

[0045] Furthermore, the instruction optimization module is established as follows:

[0046] The instruction optimization module optimizes the speed signal output by the finite-time kinematics module considering the contact force constraint between the tugboat and the ship to be towed, the speed constraint of multiple tugboats, and the ship constraint;

[0047] Contact force constraint between the tugboat and the ship to be towed; Considering the relative distance d between two tugboats, we get:

[0048]

[0049] Among them, q1(t) and q2(t) are the positions of two tugboats;

[0050] When and only when the following first constraint condition is satisfied, the relative distance of multiple tugboats should be maintained as

[0051]

[0052] Among them, is the unit vector along the x-axis of the tugboat, and r 1ho = [u 11o , v 12o T , r 2Eo = [u 21o , v 22o T ;

[0053] In the presence of the first constraint condition, the ideal balance of the target tugboat is maintained as ‖q (1,2) ‖ = d, and the first constraint condition is linear in μ 1h and μ 2h , written in the following form:

[0054] p T μ ho = 0(14)

[0055] ​​Among them, and

[0056] the speed constraints of multiple tugboats; the tugboats for collaborative handling by multiple tugboats include a bow tunnel thruster and two stern azimuth thrusters; in the Earth coordinate system, the boundaries of the surge speed, sway speed, and yaw angular velocity are as follows:

[0057]

[0058] where u i1min , v i2min , r i3min and u i1max , v i2max , r i3max are the lower boundary and the upper boundary respectively;

[0059] Ship constraints; the speed constraint conditions of the tugboat in the coordinate system of the hull to be carried, that is, the second constraint condition, are as follows:

[0060]

[0061] where and are positive constants;

[0062] and are the velocity components defined in the coordinate system of the hull to be carried, as shown below:

[0063]

[0064] where is the unit vector perpendicular to , and the second constraint condition is written as:

[0065] A1μ ho ≤f1

[0066] where A1 is a sparse matrix;

[0067]

[0068] On the premise of considering the rotational inertia of the ship to be carried, the angular rate constraint condition in the coordinate system of the hull of the ship to be carried is expressed as:

[0069]

[0070] where is the optimized angular rate; is a positive constant; the angular rate constraint condition with μ ho is expressed as:

[0071] A2μ ho ≤f2

[0072] Wherein,

[0073] Based on the above constraints, a QP problem is constructed by using the first constraint, the boundaries of surge velocity, sway velocity and yaw angular velocity, the second constraint and the angular rate constraint. The calculation formula is as follows:

[0074]

[0075] s.t.A1μ ho ≤b1

[0076] A2μ ho ≤b2

[0077] f T μ ho =0

[0078]

[0079] Wherein, μ ho =[u 11min ,v 12min ,r 13min ,u 21min ,v 22min ,r 23min T and respectively represent the lower limit and the upper limit,

[0080] The present invention also provides a storage medium, which includes a stored program. When the program runs, it executes the multi-tugboat collaborative berthing controller under any one of the above-mentioned complex multi-constraints.

[0081] The present invention also provides an electronic device, which includes a memory, a processor and a computer program stored on the memory and executable on the processor. The processor runs through the computer program to execute the multi-tugboat collaborative berthing controller under any one of the above-mentioned complex multi-constraints.

[0082] Compared with the prior art, the present invention has the following advantages:

[0083] First, compared with the currently widely used multi-tugboat berthing technology based on model prediction, the present invention introduces a linear quadratic programming method. The innovation lies in that it abandons the cumbersome iterative prediction steps, thereby greatly reducing the computational pressure and effectively reducing the resource consumption.

[0084] ​Second, compared with the existing multi-tugboat collaborative berthing method, the present invention satisfies the contact force constraint and the ship constraint, and realizes the collaborative operation of tugboats. During the multi-tugboat collaborative berthing process, the proposed method can reduce the dependence on the towing rope when the tugboats maneuver the ship to be towed.

[0085] Third, compared with the existing multi-tugboat collaborative berthing method, the present invention designs a finite-time motion controller, an extended state observer (ESO) based on a robust exact differentiator (RED), and a finite-time dynamics controller, and the closed-loop control system realizes finite-time input-to-state stability (ISS). The error of the closed-loop control system can converge to a small neighborhood of zero within a finite time. Description of the Drawings

[0086] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0087] Figure 1 It is a schematic structural diagram of the present invention.

[0088] Figure 2 It is the motion trajectory of the multi-tugboats using the proposed safety critical anti-disturbance controller of the present invention.

[0089] Figure 3 It is the tracking error ‖w i1 ‖ and ‖w i2 ‖.

[0090] Figure 4 It is the control input force of the multi-tugboats of the present invention in the coordinate system of the hull to be towed. Detailed Embodiments

[0091] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0092] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present invention are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0093] The present invention provides a multi-tugboat cooperative berthing controller structure and design method that is affected by contact force constraints, ship speed constraints, ship constraints (referring to constraints on the speed of the tugboat in the hull coordinate system being carried and the angular velocity of the ship), and environmental disturbances.

[0094] As Figure 1 shown, a multi-tugboat cooperative berthing controller under complex multi-constraints includes a finite-time kinematics module, an instruction optimization module, and a finite-time dynamics module;

[0095] The finite-time kinematics module receives the position and heading information ζ1, ζ2 of the target tugboat in the finite-time dynamics module and the desired position and heading information ζ 1d , ζ 2d , and the finite-time kinematics module outputs the desired speed μ 1hc , μ 2hc to the instruction optimization module;

[0096] The instruction optimization module receives the desired speed μ 1hc , μ 2hc from the finite-time kinematics module and the position and heading information ζ1, ζ2 of the target tugboat in the finite-time dynamics module. The instruction optimization module generates an optimized speed signal μ 1ho , μ 2ho according to the contact force constraints between the tugboat and the ship, the speed constraints of the tugboat, and the ship dynamic constraints and outputs it to the finite-time dynamics module;

[0097] The finite-time dynamics module includes a dynamics controller, an ESO based on RED, and a target tugboat; the dynamics controller receives the speed signal μ 1ho , μ 2ho, the ESO disturbance estimator based on RED and the current speed information from the target tugboat; the dynamic controller outputs the tugboat moment to the ESO based on RED and the target tugboat; the target tugboat receives the tugboat moment, and the target tugboat outputs the current speed information to the dynamic controller and the ESO based on RED.

[0098] The planar motion of the tugboat can be described by a kinematic and dynamic model with three degrees of freedom, and its expression is:

[0099]

[0100] where is the position of the i-th tugboat in the earth coordinate system, and χ i is the yaw angle of the i-th tugboat, i ∈ {1, 2}. are the surge velocity, sway velocity, and yaw angular velocity vectors in the body coordinate system of the hull being towed, respectively; is the inertia matrix; and represent the Coriolis centripetal matrix and the damping matrix, respectively; is the control input vector; represents the environmental disturbance vector; is the rotation matrix, expressed as:

[0101]

[0102] To achieve the cooperative operation of multiple tugboats, model (1) can be rewritten in the earth coordinate system as follows:

[0103]

[0104] where and represent the velocity vector, control input vector, and superimposed disturbance vector in the earth coordinate system, respectively.

[0105] A. Design of the finite-time kinematic module

[0106] Assume that the ship being towed enters the port and finally parallels the port shoreline, and the port shoreline is as follows:

[0107] i b = e b a + f b b + g b (4)

[0108] where e b , f b and g b are constants.

[0109] When the ship to be towed completes berthing, the direction of the tugboat is perpendicular to the port shoreline. The desired yaw angle χ of the tugboat id is as follows:

[0110]

[0111] where χ s = atan2(-e b / f b ) is the angle of the port shoreline. Using χ s and the relative distance d between the two tugboats, ζ 1d = [a 1d , b 1d , χ 1d T , χ 2d = [a 1d + dcos(χ s ), b 1d + dsin(χ s ), χ 2d T .

[0112] To complete the multi-tugboat collaborative berthing task, the tracking error w of the position and heading i1 = [c i1 , h i2 , χ i3 T can be written as:

[0113] w i1 = ζ i - ζ id (6)

[0114] Differentiating w i1 according to formula (3), we can get:

[0115]

[0116] A finite-time speed controller is designed in the earth coordinate system, that is:

[0117]

[0118] where P i1 = diag{j iu1 , j iv2 , j ir3} is a control gain matrix.

[0119] B. Design of the finite-time dynamics module

[0120] Based on RED, an ESO is designed as the following observer: ​​​

[0121]

[0122] Among them, is the estimated speed error. P io1 = diag{j io1 , j io2 , j io3} and P io2 = diag{j io4 , j io5 , j io6} are the observer gain matrices.

[0123] According to the super-twisting control technique, the calculation formula of the dynamic sliding surface is c i = [c i1 , c i2 , c i3 T = μ ih - μ iho , and its time derivative along (3) is:

[0124]

[0125] Design the finite-time dynamics module in the earth coordinate system:

[0126]

[0127] Among them, P id1 = diag{j id1 , j id2 , j id3} and P id2 = diag{j id4 , j id5 , j id6} are the control gain matrices.

[0128] C. Instruction Optimization Module Design

[0129] The instruction optimization module optimizes the speed signal output by the finite-time kinematics module considering the contact force constraint between the tugboat and the ship to be towed, the speed constraint of multiple tugboats, and the ship constraint.

[0130] Contact force constraint between the tugboat and the ship to be towed;

[0131] Considering the relative distance d (distance between tugboats) between two tugboats, we can obtain:

[0132]

[0133] Among them, q1(t) and q2(t) are the positions of the two tugboats.

[0134] ​The relative distance of the multi-tugboats should be maintained as

[0135]

[0136] where is the unit vector along the x-axis of the tugboat, and r 1ho = [u 11o , v 12o T , r 2Eo = [u 21o , v 22o T .

[0137] In the presence of the constraint condition (13), the ideal balance of the system (3) is maintained as ‖q (1,2) ‖ = d. For the constraint condition (13), it is linear in μ 1h and μ 2h and can be written in the following form:

[0138] p T μ ho = 0 (14)

[0139] where and

[0140] Speed constraint of multi-tugboats;

[0141] The tugboats used for collaborative handling of multi-tugboats include a bow tunnel thruster and two stern azimuth thrusters. In the earth coordinate system, the boundaries of the surge velocity, sway velocity, and yaw angular velocity are as follows:

[0142]

[0143] where u i1min , v i2min , r i3min and u i1max , v i2max , r i3max are the lower and upper boundaries respectively.

[0144] Ship constraint;

[0145] The speed constraint conditions of the tugboat in the hull coordinate system being carried are as follows:

[0146]

[0147] where and are positive constants. ​​

[0148] and are velocity components defined in the hull coordinate system of the ship being carried, as follows:

[0149]

[0150] where, is a unit vector perpendicular to . The constraint condition (16) can be written as:

[0151] A1μ ho ≤f1(17)

[0152] where, A1 is a sparse matrix;

[0153]

[0154] On the premise of considering the rotational inertia of the ship being carried, the angular rate constraint condition in the hull coordinate system of the ship being carried is expressed as:

[0155]

[0156] where, is the optimized angular rate. is a positive constant. The constraint condition (18) with μ ho is expressed as:

[0157] A2μ ho ≤f2(19)

[0158] where,

[0159] Based on the above constraint conditions, a QP problem is constructed using (14), (15), (17) and (19). The calculation formula is as follows:

[0160]

[0161] s.t.A1μ ho ≤b1

[0162] A2μ ho ≤b2

[0163] f T μ ho =0

[0164]

[0165] where, μ ho =[u 11min ,v 12min, r 13min , u 21min , v 22min , r 23min T and

[0166] represent the lower limit and the upper limit respectively,

[0167] The simulation results are as Figures 2 - 4 shown. Figure 2 The motion trajectories during the collaborative berthing process of multiple tugboats under the controller proposed by the present invention are given. It can be seen that the multiple tugboats achieve collaborative berthing according to the reference trajectory. Figure 3 The tracking errors ‖w i1 ‖ and ‖w i2 ‖ curve graphs during the collaborative berthing of multiple tugboats of the present invention are given. It can be seen that the tracking errors of the multiple tugboats converge to near zero within a finite time, indicating that the proposed method effectively realizes the tracking of the reference trajectory. Figure 4 is the control input force of the multiple tugboats in the hull coordinate system of the ship to be carried. It can be seen that the forces and torques output by the multiple tugboats are basically consistent.

[0168] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some 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 invention.​

Claims

1. A multi-tugboat collaborative berthing controller under complex multiple constraints, characterized in that, It includes a finite-time kinematics module, an instruction optimization module, and a finite-time dynamics module; The finite-time kinematics module receives the position and heading information ζ1, ζ2 of the target tugboat in the finite-time dynamics module and the desired position and heading information ζ 1d , ζ 2d , and the finite-time kinematics module outputs the desired velocity μ 1hc , μ 2hc to the instruction optimization module; The instruction optimization module receives the desired velocity μ from the finite-time kinematics module 1hc , μ 2hc and the position and heading information ζ1, ζ2 of the target tugboat from the finite-time dynamics module. The instruction optimization module generates an optimized velocity signal μ based on the contact force constraint between the tugboat and the ship, the velocity constraint of the tugboat, and the ship dynamics constraint 1ho , μ 2ho and outputs it to the finite-time dynamics module; The finite-time dynamics module includes a dynamics controller, an extended state observer based on a robust differentiator, and a target tugboat; the dynamics controller receives a velocity signal μ from the command optimization module 1ho , μ 2ho , the disturbance estimation quantity from the extended state observer based on the robust differentiator, and the current velocity information from the target tugboat; the dynamics controller outputs a tugboat torque to the extended state observer based on the robust differentiator and the target tugboat; the target tugboat receives the tugboat torque, and the target tugboat outputs the current velocity information to the dynamics controller and the extended state observer based on the robust differentiator.

2. The multi-tugboat collaborative berthing controller under complex multi-constraints according to claim 1, wherein The mathematical model of the target tugboat includes a kinematic model and a dynamic model, and the expressions are as follows: wherein, is the position of the i-th tugboat in the earth coordinate system, χ i is the yaw angle of the i-th tugboat, i ∈ {1, 2}; are respectively the surge velocity, sway velocity and yaw angular velocity vectors in the hull coordinate system to be transported; is the inertia matrix; and respectively represent the Coriolis centripetal matrix and the damping matrix; is the control input vector; represents the environmental disturbance vector; is a rotation matrix, expressed as: The kinematic model and the dynamic model are rewritten in the Earth coordinate system as follows: where, μ iE = [u ia , v ib , r iχ T = S i (χ i )μ i , υ ih = [υ ia , υ ib , υ iχ T = S i (χ i )M i -1 υ i ; respectively represent the velocity vector, control input vector, and superimposed disturbance vector in the Earth coordinate system.​​ 3. The multi-tugboat collaborative berthing controller under complex multi-constraints according to claim 1, characterized in that The establishment steps of the finite-time kinematics module are as follows: Assume that the ship to be transported enters the port and finally parallels the port shoreline, and the port shoreline is as follows: i b = e b a + f b b + g b Among them, where e b , f b and g b are constants; When the ship to be towed completes berthing, the direction of the tugboat is perpendicular to the port shoreline, and the desired yaw angle χ of the tugboat id is as follows: where χ s = atan2(-e b / f b ) is the angle of the port coastline, and using χ s and the relative distance d between the two tugboats, it is designed that: ζ 1d = [a 1d , b 1d , χ 1d T , χ 2d = [a 1d + d cos(χ s ), b 1d + d sin(χ s ), χ 2d T ;​​ To complete the multi-tugboat collaborative berthing task, the tracking errors w of position and heading i1 = [c i1 , h i2 , χ i3 T is written as:​ A finite-time speed controller is designed in the Earth coordinate system, that is: where, P i1 = diag{j iu1 , j iv2 , j ir3} is a control gain matrix.

4. The multi-tugboat collaborative berthing controller under complex multi-constraints according to claim 1, characterized in that The establishment steps of the finite-time dynamics module are as follows: An observer is designed based on the robust differentiator extended state observer as follows: wherein, For estimating the speed error, P io1 = diag{j io1 , j io2 , j io3} and P io2 = diag{j io4 , j io5 , j io6} are observer gain matrices; Definition and Using the kinematic model and dynamic model in the Earth coordinate system, the error dynamics of the extended state observer based on the robust differentiator are as follows: According to the supercoiling control technology, the calculation formula of the dynamic sliding surface is c i =[c i1 ,c i2 ,c i3 T =μ ih -μ iho , and its time derivative is:​ Design the finite-time dynamics module in the Earth coordinate system: where, P id1 = diag{j id1 , j id2 , j id3} and P id2 = diag{j id4 , j id5 , j id6} are control gain matrices.

5. The multi-tugboat collaborative berthing controller under complex multi-constraints according to claim 1, wherein The establishment steps of the instruction optimization module are as follows: The instruction optimization module optimizes the speed signal output by the finite-time kinematics module considering the contact force constraint between the tugboat and the ship to be transported, the speed constraint of multiple tugboats, and the ship constraint; The contact force constraint between the tugboat and the ship to be transported; considering the relative distance d between two tugboats, we get: where q1(t) and q2(t) are the positions of the two tugboats; The relative distances of the multiple tugboats shall be maintained if and only if the following first constraint condition is satisfied : wherein, is a unit vector along the x-axis direction of the tugboat, and r 1ho = [u 11o , v 12o T , r 2Eo = [u 21o , v 22o T ;​​ In the presence of the first constraint, the ideal balance of the target tugboat remains ‖q (1,2) ‖ = d, and the first constraint is linearly related in μ 1h and μ 2h and is written in the following form: Among them, and The speed constraint of multiple tugboats; the tugboats used for the collaborative transportation of multiple tugboats include a bow tunnel thruster and two stern azimuth thrusters; in the Earth coordinate system, the boundaries of the surge speed, sway speed, and yaw angular velocity are as follows: Among them, u i1min 、v i2min 、r i3min and u i1max 、v i2max 、r i3max are the lower boundary and the upper boundary respectively; The ship constraint; the speed constraint condition of the tugboat in the hull coordinate system of the ship to be transported, that is, the second constraint condition, is as follows: wherein, and are positive constants; and are velocity components defined in the hull coordinate system being carried, as follows: Among them, is a unit vector perpendicular to , and the second constraint condition is written as: A1μ ho ≤ f1 Among them, A1 is a sparse matrix; On the premise of considering the rotational inertia of the ship to be transported, the angular rate constraint condition in the hull coordinate system of the ship to be transported is expressed as: Among them, is the optimized angular rate; is a positive constant; with μ ho The angular rate constraint condition is expressed as: A2μ ho ≤f2 Among them, Based on the above constraint conditions, a QP problem is constructed using the first constraint condition, the boundaries of the surge speed, sway speed, and yaw angular velocity, the second constraint condition, and the angular rate constraint condition, and the calculation formula is as follows: s.t. A1μ ho ≤b1 A2μ ho ≤b2 f T μ ho = 0 Among them, and represent the lower limit and the upper limit respectively, 6. A storage medium, characterized in that, The storage medium includes a stored program, wherein when the program runs, it executes the multi-tugboat collaborative berthing controller under complex multi-constraints described in any one of claims 1 to 5.

7. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor runs through the computer program to execute the multi-tugboat collaborative berthing controller under complex multi-constraints described in any one of claims 1 to 5.

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