Cable-free double-tugboat cooperative carrying controller based on neurodynamics algorithm

Abstract

The invention provides a cable-free double-tugboat cooperative carrying controller based on a neurodynamics algorithm. The cable-free double-tugboat cooperative carrying controller comprises a tugboat kinematics sub-controller, a tugboat speed optimization sub-controller and a tugboat instruction optimization sub-controller. The first tugboat kinematics sub-controller receives position information and course angle information from the first tugboat; receiving expected position information and expected course angle information from the first tugboat; the first tugboat kinematics sub-controller sends speed information to a first tugboat speed optimization sub-controller; the tugboat speed optimization sub-controller comprises a first tugboat speed optimization sub-controller and a second tugboat speed optimization sub-controller; according to the method, obstacle avoidance constraints are converted into explicit mathematical conditions capable of being embedded into a control framework in real time, it is forcibly guaranteed that the tugboat formation carrying process is always in a safe operation area, and the problems of obstacle avoidance response delay and safety constraint softening in a traditional method are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of dual tugboat cooperative control technology, and more particularly to a cableless dual tugboat cooperative transport controller based on a neurodynamics algorithm. Background Technology

[0002] With the continuous growth of global demand for marine logistics and engineering transportation, the handling of large cargoes or offshore platforms at sea is becoming increasingly frequent. These cargoes are enormous in size and weight, and single tugboats, limited by their power output and maneuvering precision, often struggle to complete the handling tasks independently. Therefore, a coordinated control system between two tugboats is essential for efficient handling or precise positioning and installation. In actual operations, the marine environment is complex and ever-changing, with waterways often containing obstacles such as reefs, buoys, and other vessels. Single tugboats not only struggle to meet complex obstacle avoidance requirements but also exhibit slow steering and braking when handling large cargoes, resulting in extremely high obstacle avoidance risks. However, coordinated operation between two tugboats, through contact force constraints, formation constraints, and collision avoidance constraints, can ensure stable cargo transport while achieving efficient obstacle avoidance. This coordinated control mode for two tugboats not only meets the obstacle avoidance requirements of complex waterways but also significantly improves the feasibility and operational efficiency of maritime handling of large cargoes.

[0003] There are still some problems in the existing dual-tugboat cooperative handling control methods that need to be solved: First, existing multi-tugboat collaborative handling control methods mainly focus on system stability and collaborative operation performance optimization, failing to fully consider obstacle avoidance issues in the operating environment. This leads to severe collision risks in practical applications. This lack of collision avoidance capability may not only cause equipment damage and safety accidents, but also significantly reduce the reliability and practicality of the entire collaborative handling system.

[0004] Second, existing multi-tugboat cooperative transport control methods primarily use cables to connect tugboats to surface targets, neglecting the influence of contact forces between the tugboats and the targets. Due to the diversity of surface targets, cable connections face numerous challenges. For example, some smooth-surfaced targets may not provide sufficient friction to secure the cables; and some structurally complex targets may lack ideal locations for cable winding or anchoring, making it difficult to find a fixed position. Therefore, it is necessary to research multi-tugboat cooperative transport control methods that do not rely on cables.

[0005] Third, most existing multi-tugboat cooperative handling control methods fail to adequately consider the impact of the relative positions and heading angles between tugboats on the system's force balance. Due to the lack of precise formation coordination control strategies, tugboats often exhibit asynchronous movement during actual operations. This not only leads to severe swaying and torsion of the transported load but also causes mutual antagonism between tugboats. Therefore, it is necessary to research formation maintenance control methods suitable for cooperative handling processes to improve the safety and efficiency of the handling process. Summary of the Invention

[0006] In view of this, the purpose of this invention is to propose a cableless dual tugboat cooperative transport controller based on a neurodynamic algorithm, so as to solve the technical problem that existing dual tugboat cooperative transport control methods fail to fully consider obstacle avoidance in the working environment.

[0007] The technical means employed in this invention are as follows: A cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm includes a kinematics sub-controller for the tugboats, a speed optimization sub-controller for the tugboats, and a command optimization sub-controller for the tugboats. The tugboat's kinematic controller includes a first tugboat kinematic controller and a second tugboat kinematic controller. The first tugboat kinematic controller receives position information and attitude information from the first tugboat. ; Receive the desired position information and desired attitude information from the first tugboat. The first tugboat kinematic controller sends speed information. To the first tugboat speed optimization sub-controller; The second tugboat's kinematic controller receives position information and attitude information from the second tugboat. ; Receive the desired position information and desired attitude information from the second tugboat. The second tugboat kinematic controller sends speed information. To the second tugboat speed optimization sub-controller; The tugboat speed optimization sub-controller includes a first tugboat speed optimization sub-controller and a second tugboat speed optimization sub-controller; The first tugboat speed optimization sub-controller receives speed information from the first tugboat kinematics sub-controller. The first tugboat speed optimization sub-controller receives position information and attitude information from the first tugboat. The first tugboat speed optimization sub-controller receives speed information from the instruction optimization sub-controller. And the attitude information of the second tugboat. The first tugboat speed optimization sub-controller sends the position information and attitude information of the first tugboat. And the speed information of the first tugboat's motion control unit. The first tugboat speed optimization sub-controller sends optimized speed information to the instruction optimization sub-controller. To the first tugboat; The second tugboat speed optimization sub-controller receives speed information from the second tugboat kinematics sub-controller. The second tugboat speed optimization sub-controller receives position information and attitude information from the second tugboat. The second tugboat speed optimization sub-controller receives speed information from the command optimization sub-controller. And the attitude information of the first tugboat The second tugboat speed optimization sub-controller sends the position information and attitude information of the second tugboat. And the speed information of the second tugboat's motion control unit. The second tugboat speed optimization sub-controller sends the optimized speed information to the instruction optimization sub-controller. To the second tugboat; The instruction optimization sub-controller receives attitude information of the first tugboat from the first tugboat speed optimization sub-controller. and speed information The instruction optimization sub-controller receives attitude information of the second tugboat from the second tugboat speed optimization sub-controller. and speed information The instruction optimization sub-controller sends the attitude information of the second tugboat. and the speed information of the first tugboat The command optimization sub-controller sends the attitude information of the first tugboat to the first tugboat speed optimization sub-controller. and the speed information of the first tugboat To the second tugboat speed optimization sub-controller.

[0008] Furthermore, the kinematic expressions for the first and second tugboats are as follows: (1) In the formula, Representing the tugboat Position vector in a fixed Earth reference coordinate system; , It is the sway velocity component in the ship's coordinate system. It is the sway velocity component in the ship's coordinate system; It is a rotation matrix, expressed as: .

[0009] Furthermore, the steps for establishing the kinematic control laws of the first tugboat kinematic sub-controller and the second tugboat kinematic sub-controller are as follows: trajectory tracking The error is expressed as: (3) In the formula, , It refers to the desired position and course; right Taking the derivative, we get: (4) In the Earth coordinate system, the kinematic control law is: (5) (6) In the formula, and It is a positive number.

[0010] Furthermore, the instruction optimization sub-controller includes tugboat formation constraints, load speed constraints, load speed angle constraints, and static obstacle constraints.

[0011] Furthermore, the formation constraints are as follows: To achieve coordinated transport, the relative distance between the two tugboats remains constant at all times. The formation constraints are as follows: (7) in, , yes The unit vector, and for any ,have ; Formation constraints are used and It is expressed as follows: (8) In the formula, .

[0012] Furthermore, the load speed constraint is as follows: The velocity constraint of the tugboat in the load coordinate system is: (9) In the formula, , , It is perpendicular to unit vector, and It is the optimized speed signal. and It is a positive number; The velocity of the tugboat in the load coordinate system is expressed as follows: (10) In the formula: (11) (12) In the formula, It is a unit vector.

[0013] Furthermore, the load velocity angle constraint is as follows: The angular rate constraint of the load is given as follows: (13) In the formula, It is the load angular velocity. It is the optimized angular velocity. It is a positive number; The load velocity angle constraint is rewritten as follows: (14) (15) .

[0014] Furthermore, the static obstacle constraints are as follows: The control barrier function is defined as follows:

[0015] The control barrier function constraints are specifically described as follows: (17) In the formula, ; It refers to the location of static obstacles. Indicates the safe collision avoidance radius.

[0016] Furthermore, the steps for establishing the speed optimization sub-controller for the tugboat are as follows: A quadratic programming problem is constructed to obtain an optimized velocity signal that satisfies the constraints in the instruction optimization sub-controller. The quadratic programming problem is as follows: (18) (19) (20) (twenty one) In the formula, ; To generate real-time collaborative optimization transport speed signals, a neurodynamic optimization method is used to solve a quadratic programming problem, as shown in the following formula: (twenty two) In the formula, Statement The gradient vector; express The gradient vector; The formula is as follows: (twenty three) Projection function The formula is as follows: (twenty four) In the formula, ; ; ; .

[0017] Compared with the prior art, the present invention has the following advantages: First, compared with existing multi-tugboat cooperative handling control methods, this invention proposes a multi-tugboat handling control method based on a control obstacle function. This method transforms obstacle avoidance constraints into explicit mathematical conditions that can be embedded into the control framework in real time, ensuring that the tugboat convoy remains within a safe operating area throughout the handling process. This effectively solves the problems of delayed obstacle avoidance response and softened safety constraints in traditional methods.

[0018] Secondly, compared with existing multi-tugboat collaborative handling control design methods, this invention fully considers and satisfies contact force constraints and ship constraint conditions, successfully realizing efficient collaborative handling operations between tugboats. It eliminates the tugboats' dependence on cables during collaborative handling, effectively improving the efficiency and safety of multi-tugboat collaborative handling operations. Third, compared with existing multi-tugboat collaborative handling and connection strategies, this invention fully considers and satisfies the constraints of the formation between tugboats, successfully achieving formation maintenance between them. By maintaining the formation between tugboats, the operational difficulty is reduced, and the efficiency and accuracy of tugboat control are improved. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the controller of the present invention.

[0021] Figure 2 This is a schematic diagram of two tugboats in the ship's coordinate system.

[0022] Figure 3 This is a schematic diagram of the motion trajectory of two tugboats cooperating in transport under the constraints of this invention.

[0023] Figure 4 This is a schematic diagram illustrating the relative distance between tugboats during collaborative transport, as described in this invention.

[0024] Figure 5 This is a schematic diagram illustrating the optimized speed of the tugboat during the collaborative transport process of this invention.

[0025] Figure 6 This is a schematic diagram illustrating the optimized angular rate of the tugboat during the collaborative transport process of this invention. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] like Figure 1As shown, this invention provides a cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm, including a kinematics sub-controller for the tugboats, a speed optimization sub-controller for the tugboats, and a command optimization sub-controller for the tugboats; a schematic diagram of the two tugboats in the hull coordinate system is shown below. Figure 2 As shown.

[0029] The tugboat's kinematic controller includes a first tugboat kinematic controller and a second tugboat kinematic controller. The first tugboat kinematic controller receives position information and attitude information from the first tugboat. ; Receive the desired position information and desired attitude information from the first tugboat. The first tugboat kinematic controller sends speed information. To the first tugboat speed optimization sub-controller; The second tugboat's kinematic controller receives position information and attitude information from the second tugboat. ; Receive the desired position information and desired attitude information from the second tugboat. The second tugboat kinematic controller sends speed information. To the second tugboat speed optimization sub-controller; The tugboat speed optimization sub-controller includes a first tugboat speed optimization sub-controller and a second tugboat speed optimization sub-controller; The first tugboat speed optimization sub-controller receives speed information from the first tugboat kinematics sub-controller. The first tugboat speed optimization sub-controller receives position information and attitude information from the first tugboat. The first tugboat speed optimization sub-controller receives speed information from the instruction optimization sub-controller. And the attitude information of the second tugboat. The first tugboat speed optimization sub-controller sends the position information and attitude information of the first tugboat. And the speed information of the first tugboat's motion control unit. The first tugboat speed optimization sub-controller sends optimized speed information to the instruction optimization sub-controller. To the first tugboat; The second tugboat speed optimization sub-controller receives speed information from the second tugboat kinematics sub-controller. The second tugboat speed optimization sub-controller receives position information and attitude information from the second tugboat. The second tugboat speed optimization sub-controller receives speed information from the command optimization sub-controller. And the attitude information of the first tugboat The second tugboat speed optimization sub-controller sends the position information and attitude information of the second tugboat. And the speed information of the second tugboat's motion control unit. The second tugboat speed optimization sub-controller sends the optimized speed information to the instruction optimization sub-controller. To the second tugboat; The instruction optimization sub-controller receives attitude information of the first tugboat from the first tugboat speed optimization sub-controller. and speed information The instruction optimization sub-controller receives attitude information of the second tugboat from the second tugboat speed optimization sub-controller. and speed information The instruction optimization sub-controller sends the attitude information of the second tugboat. and the speed information of the first tugboat The command optimization sub-controller sends the attitude information of the first tugboat to the first tugboat speed optimization sub-controller. and the speed information of the first tugboat To the second tugboat speed optimization sub-controller.

[0030] The motion of the tugboats can be described using two frames of reference: an Earth coordinate system and a ship coordinate system. The kinematic expressions for the first and second tugboats are as follows: (1) In the formula, Representing the tugboat Position vector in a fixed Earth reference coordinate system; , It is the sway velocity component in the ship's coordinate system. It is the sway velocity component in the ship's coordinate system; It is a rotation matrix, expressed as: (2) The steps for establishing the kinematic control laws for the first and second tugboat kinematic sub-controllers are as follows: To complete the collaborative transportation task, trajectory tracking The error is expressed as: (3) In the formula, , It refers to the desired position and course; right Taking the derivative, we get: (4) In the Earth coordinate system, the kinematic control law is: (5) (6) In the formula, and It is a positive number.

[0031] The instruction optimization sub-controller includes tugboat formation constraints, load speed constraints, load speed angle constraints, and static obstacle constraints.

[0032] The formation constraints are as follows: To achieve coordinated transport, the relative distance between the two tugboats remains constant at all times. The formation constraints are as follows: (7) in, , yes The unit vector, and for any ,have ; Constraint (7) can be used and It is expressed as follows: (8) In the formula, .

[0033] The load speed constraint is as follows: The velocity constraint of the tugboat in the load coordinate system is: (9) In the formula, , , It is perpendicular to unit vector, and It is the optimized speed signal. and It is a positive number; Constraint (9) can be written as: (10) In the formula: (11) (12) In the formula, It is a unit vector.

[0034] The load velocity angle constraint is as follows: The angular rate constraint of the load is given as follows: (13) In the formula, It is the load angular velocity. It is the optimized angular velocity. It is a positive number; Constraint (13) is rewritten as follows: (14) (15) (16) The static obstacle constraints are as follows: The control barrier function is defined as follows:

[0035] The control barrier function constraints are specifically described as follows: (17) In the formula, ; It refers to the location of static obstacles. Indicates the safe collision avoidance radius.

[0036] The steps for establishing the speed optimization sub-controller for the tugboat are as follows: To achieve coordinated tugboat tasks, a quadratic programming problem is constructed to obtain an optimized speed signal that satisfies the constraints in the instruction optimization sub-controller. The quadratic programming problem is as follows: (18) (19) (20) (twenty one) In the formula, ; To generate real-time collaborative optimization transport speed signals, a neurodynamic optimization method is used to solve a quadratic programming problem, as shown in the following formula: (twenty two) In the formula, Statement The gradient vector; express The gradient vector; The formula is as follows: (twenty three) Projection function The formula is as follows: (twenty four) In the formula, ; ; ; .

[0037] This embodiment verifies the effectiveness of the proposed safety-critical control method for collaborative transport of two tugboats through simulation. An open water area is selected to implement the collaborative transport of the two tugboats. The initial positions and angles of the two tugboats are as follows: and The desired position and angle are respectively and The controller parameters are set to... , , , , , , , , , , , The relative distance between the two tugboats The constraint parameters are: , , , , Parameters of static obstacles , , .

[0038] Figure 3 The study revealed the movement trajectory of the tugboats, and the results showed that the method proposed in this study can effectively enable two tugboats to carry out collaborative transport tasks. Figure 4 The relative distance between the two tugboats during the collaborative transport process was described in detail, and the results showed that the distance remained constant. Figure 5 and Figure 6 The velocity component constraints of the tugboat in the coordinate system of the object being transported are clearly shown.

[0039] This study proposes a neurodynamic optimization control method for the cooperative transport problem involving two tugboats without cables. Based on the kinematic model of the tugboats and contact force constraints, a cooperative control strategy applicable to multiple tugboats is designed: a kinematic control law is constructed for each tugboat to track the desired position and heading, and the cooperative velocity signal satisfying the collision avoidance constraint is solved in real time using a neurodynamic optimization method, ensuring that the tugboat formation achieves cooperative optimization of safe collision avoidance and target position tracking during dynamic adjustments. Simulation results show that the proposed method can effectively complete the cooperative transport task of multiple tugboats under complex constraints, verifying its engineering practicality and control effectiveness.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm, characterized in that: This includes the kinematics sub-controller for the tugboat, the speed optimization sub-controller for the tugboat, and the command optimization sub-controller for the tugboat; The tugboat's kinematic controller includes a first tugboat kinematic controller and a second tugboat kinematic controller. The first tugboat kinematic controller receives position information and attitude information from the first tugboat. ; Receive the desired position information and desired attitude information from the first tugboat. The first tugboat kinematic controller sends speed information. To the first tugboat speed optimization sub-controller; The second tugboat's kinematic controller receives position information and attitude information from the second tugboat. ; Receive the desired position information and desired attitude information from the second tugboat. The second tugboat kinematic controller sends speed information. To the second tugboat speed optimization sub-controller; The tugboat speed optimization sub-controller includes a first tugboat speed optimization sub-controller and a second tugboat speed optimization sub-controller; The first tugboat speed optimization sub-controller receives speed information from the first tugboat kinematics sub-controller. The first tugboat speed optimization sub-controller receives position information and attitude information from the first tugboat. The first tugboat speed optimization sub-controller receives speed information from the instruction optimization sub-controller. And the attitude information of the second tugboat. The first tugboat speed optimization sub-controller sends the position information and attitude information of the first tugboat. And the speed information of the first tugboat's motion control unit. The first tugboat speed optimization sub-controller sends optimized speed information to the instruction optimization sub-controller. To the first tugboat; The second tugboat speed optimization sub-controller receives speed information from the second tugboat kinematics sub-controller. The second tugboat speed optimization sub-controller receives position information and attitude information from the second tugboat. ; The second tugboat speed optimization sub-controller receives speed information from the command optimization sub-controller. And the attitude information of the first tugboat The second tugboat speed optimization sub-controller sends the position information and attitude information of the second tugboat. And the speed information of the second tugboat's motion control unit. The second tugboat speed optimization sub-controller sends the optimized speed information to the instruction optimization sub-controller. To the second tugboat; The instruction optimization sub-controller receives attitude information of the first tugboat from the first tugboat speed optimization sub-controller. and speed information The instruction optimization sub-controller receives attitude information of the second tugboat from the second tugboat speed optimization sub-controller. and speed information The instruction optimization sub-controller sends the attitude information of the second tugboat. and the speed information of the first tugboat The command optimization sub-controller sends the attitude information of the first tugboat to the first tugboat speed optimization sub-controller. and the speed information of the first tugboat To the second tugboat speed optimization sub-controller.

2. The cableless dual-tugboat cooperative transport controller based on neurodynamics algorithm according to claim 1, characterized in that, The kinematic expressions for the first and second tugboats are as follows: （1） In the formula, Representing the tugboat Position vector in a fixed Earth reference coordinate system; , It is the sway velocity component in the ship's coordinate system. It is the sway velocity component in the ship's coordinate system; It is a rotation matrix, expressed as: 。 3. The cableless dual-tugboat cooperative transport controller based on neurodynamics algorithm according to claim 1, characterized in that, The steps for establishing the kinematic control laws for the first and second tugboat kinematic sub-controllers are as follows: trajectory tracking The error is expressed as: （3） In the formula, , It refers to the desired position and course; right Taking the derivative, we get: （4） In the Earth coordinate system, the kinematic control law is: （5） （6） In the formula, and It is a positive number.

4. The cableless dual-tugboat cooperative transport controller based on neurodynamics algorithm according to claim 1, characterized in that, The instruction optimization sub-controller includes tugboat formation constraints, load speed constraints, load speed angle constraints, and static obstacle constraints.

5. The cableless dual-tugboat cooperative transport controller based on neurodynamics algorithm according to claim 4, characterized in that, The formation constraints are as follows: To achieve coordinated transport, the relative distance between the two tugboats remains constant at all times. The formation constraints are as follows: （7） in, , yes The unit vector, and for any ,have ; Formation constraints are used and It is expressed as follows: （8） In the formula, .

6. The cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm according to claim 5, characterized in that, The load speed constraint is as follows: The velocity constraint of the tugboat in the load coordinate system is: （9） In the formula, , , It is perpendicular to unit vector, and It is the optimized speed signal. and It is a positive number; The velocity of the tugboat in the load coordinate system is expressed as follows: （10） In the formula: （11） （12） In the formula, It is a unit vector.

7. The cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm according to claim 6, characterized in that, The load velocity angle constraint is as follows: The angular rate constraint of the load is given as follows: （13） In the formula, It is the load angular velocity. It is the optimized angular velocity. It is a positive number; The load velocity angle constraint is rewritten as follows: （14） （15） 。 8. The cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm according to claim 7, characterized in that, The static obstacle constraints are as follows: The control barrier function is defined as follows: The control barrier function constraint is specifically described as follows: （17） In the formula, ; It refers to the location of static obstacles. Indicates the safe collision avoidance radius.

9. The cableless dual-tugboat cooperative transport controller based on a neurodynamics algorithm according to claim 1, characterized in that, The steps for establishing the speed optimization sub-controller for the tugboat are as follows: A quadratic programming problem is constructed to obtain an optimized velocity signal that satisfies the constraints in the instruction optimization sub-controller. The quadratic programming problem is as follows: （18） （19） （20） （21） In the formula, ; To generate real-time collaborative optimization transport speed signals, a neurodynamic optimization method is used to solve a quadratic programming problem, as shown in the following formula: （22） In the formula, Statement The gradient vector; express The gradient vector; The formula is as follows: （23） Projection function The formula is as follows: （24） In the formula, ; ; ; .

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