One-way channel ship berthing and unberthing planning algorithm

Abstract

The application discloses a one-way channel ship berthing and unberthing planning algorithm, and establishes a mixed integer programming model according to the one-way channel safe navigation rule, so as to improve the navigation efficiency and the utilization rate of the sea port water area, and reasonably plans the ship berthing and unberthing time sequence, specifically comprising the following steps: S1, classifying the ships in different stages, and setting the priority level to 1-5 levels. The application is aimed at the safety problem of ship berthing and unberthing between ships in a harbor basin and a channel, converts the problem into a safety problem of ensuring the berthing and unberthing of any two ships in the harbor basin and the channel, then obtains the berthing and unberthing navigation track according to the ship information and the berthing position, analyzes the influence between any two navigation tracks as basic information, converts the safety problem in the navigation process into a linear constraint, creates a port safety basic information database, efficiently and accurately expresses the mutual influence of the ships in the harbor basin and the channel in the berthing and unberthing process, can reasonably arrange the berthing and unberthing time of the ships, and improves the navigation efficiency.

Description

TECHNICAL FIELD

[0001] The application relates to the field of ship berthing and unberthing planning, in particular to a one-way channel ship berthing and unberthing planning algorithm. BACKGROUND

[0002] During the berthing, unberthing and shifting of a ship, the safety of navigation in a dock and a channel, the berthing of a deep-draft ship according to a tide, the influence of a tugboat on the berthing, unberthing and shifting, the unloading efficiency of a berth and other factors; under the premise of meeting the above factors, reasonably arranging the berthing and unberthing time of the ship can improve the navigation efficiency.

[0003] Therefore, how to reasonably arrange the berthing and unberthing time of the ship and improve the navigation efficiency is a problem to be solved at present; in view of this, the application discloses a one-way channel ship berthing and unberthing planning algorithm. SUMMARY

[0004] The application aims to reasonably arrange the berthing and unberthing time of the ship and improve the navigation efficiency, and discloses a one-way channel ship berthing and unberthing planning algorithm.

[0005] In order to achieve the above object, the application adopts the following technical scheme:

[0006] The one-way channel ship berthing and unberthing planning algorithm is characterized in that a mixed integer programming model is established according to the importance of the ship, and the berthing and unberthing scheme of the ship is reasonably planned, and specifically includes the following steps:

[0007] S1, the characteristics of the ship in different stages are selected, the priority is set to 1-5 levels, and the influence of the importance of the ship itself on the berthing and unberthing of the ship is emphasized;

[0008] S2, a sequence penalty matrix is established, and the theoretical berthing and unberthing sequence is obtained from the ship arrival sequence and the priority;

[0009] S3, positive and negative deviation variables are defined for the decision variables of the berthing time and the unberthing time, and soft constraints are applied to ensure the feasibility and accuracy of the model;

[0010] S4, according to the influence range of different constraint conditions, the optimal calculation range is found, different dock berths are divided, the number of single ship calculation is reduced, and the operation speed is improved;

[0011] S5, according to the safety requirements of the berthing and unberthing of the ship in the dock and the channel, the berthing and unberthing navigation track is obtained according to the ship information and the berthing berth, the correlation between any two navigation tracks is comprehensively analyzed, and the correlation is converted into a constraint condition to ensure the safety in the navigation process;

[0012] S6, converting the influence of the tidal change into a navigable time period, ensuring that the berthing and unberthing process is completed within the navigable time period, and converting it into a linear constraint to ensure that the berthing and unberthing process is restricted by the tide;

[0013] S7, obtaining the start and end times of the use of the tugboat by each ship according to the relationship between the number of tugboats used, the start time and the berthing and unberthing time during the berthing and unberthing process of each ship; considering the sailing time of the tugboat between any two berthing and unberthing processes, ensuring that the tugboat efficiently completes each plan through linear constraints, and further ensuring that the berthing and unberthing plan meets the demand for the use of the tugboat;

[0014] S8, the moving process only affects the in-and-out of the port basin, and the safety problem caused by the moving process is converted into a safety guarantee problem in the moving affected water area, and then the ship sailing track is obtained according to the ship information and the berthing and moving berths, and the correlation between any two sailing tracks is analyzed as basic information, which is converted into a linear constraint to ensure safety during sailing.

[0015] S9, constructing an objective function according to the above constraints, setting the minimum waiting time of the ship in the port and the highest utilization rate of the berth as the solving goal, and solving the model.

[0016] Preferably, the mixed integer programming model is solved by using a Gurobi optimizer.

[0017] Preferably, the safety problem of the berthing and unberthing of the ships in the port basin and the channel is not included in the moving process in S5.

[0018] Preferably, the safety problem of the berthing and unberthing of the ships in the port basin and the channel is not included in the moving process in S5.

[0019] Preferably, the constraint conditions in S7 include the number of tugboats, the flexible time constraint of each tugboat working on a ship, and the non-conflict constraint of the working time of multiple tugboats.

[0020] Preferably, the non-conflict constraint of the working time of multiple tugboats includes the non-conflict between the working of each tugboat on different ships.

[0021] Preferably, the moving process only affects the in-and-out of the port basin in S8, and the safety problem caused by the moving process is converted into a safety guarantee problem in the port basin, and the safety problem of the berthing and unberthing and the moving is specifically explained as: any M ship berthing, N ship unberthing, Q ship moving, the difference process is M ship berthing-Q ship moving, N ship unberthing-Q ship moving.

[0022] The beneficial effects of the present application are:

[0023] The present application is directed to the safety problem of ship-to-ship berthing and unberthing in a harbor basin and a channel, converts the problem into a safety problem of ensuring the safety of any two ships berthing and unberthing in a harbor basin and a channel, then obtains berthing and unberthing trajectories according to ship information and berthing positions, analyzes the influence between any two trajectories as basic information, converts the influence into linear constraints to ensure safety during navigation, creates a harbor safety database, efficiently and accurately expresses the mutual influence of ships in a harbor basin and a channel during berthing and unberthing, and reasonably arranges the berthing and unberthing time of ships to improve navigation efficiency. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments in the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0025] A one-way channel ship berthing and unberthing planning algorithm, characterized by establishing a mixed integer programming model according to the importance of the ship, and reasonably planning the berthing and unberthing scheme of the ship, specifically comprising the following steps:

[0026] S1, selecting the characteristics of ships in different stages, setting the priority level to 1-5, and emphasizing the influence of the importance of the ship itself on the berthing and unberthing of the ship;

[0027] S2, establishing a sequence penalty matrix, obtaining the theoretical berthing and unberthing sequence from the ship arrival sequence and priority;

[0028] S3, defining positive and negative deviation variables for the decision variables of berthing time and unberthing time, applying soft constraints to ensure the feasibility and accuracy of the model;

[0029] S4, according to the influence range of different constraint conditions, finding the optimal calculation range, dividing different harbor basin berthing positions, reducing the number of single ship calculations, and improving the operation speed;

[0030] S5, according to the safety requirements of ship-to-ship berthing and unberthing in a harbor basin and a channel, obtaining the berthing and unberthing trajectory according to the ship information and berthing position, comprehensively analyzing the correlation between any two trajectories, converting it into a constraint condition to ensure safety during navigation;

[0031] S6, converting the influence of tidal changes into a navigable time period, ensuring that the berthing and unberthing process is completed within the navigable time period, and converting it into a linear constraint to ensure the influence of tidal water during the berthing and unberthing process;

[0032] S7, according to the relationship between the number of tugs used by each ship during the berthing and unberthing process, the starting time and the berthing and unberthing time, the starting and ending time of each ship using the tug is obtained; considering the sailing time of the tug between any two berthing and unberthing dynamics, the linear constraint is used to ensure that the tug efficiently completes each plan, and then ensure that the berthing and unberthing plan meets the demand of the tug;

[0033] S8, the moving process only affects the ships entering and leaving the harbor in the harbor basin, and the safety problem caused by the moving is converted into a safety guarantee problem in the moving affected water area, and then the ship sailing track is obtained according to the ship information and the berthing berth and the moving berth, the correlation between any two sailing tracks is analyzed as basic information, and is converted into a linear constraint to ensure the safety problem in the sailing process.

[0034] S9, according to the above constraint conditions, a target function is constructed, and the minimum waiting time of the ship in the port and the highest utilization rate of the berth are set as the solving target, and the model is solved.

[0035] In the application, the mixed integer programming model is solved by using Gurobi optimizer.

[0036] For S2, the sequence penalty matrix is established according to the ship arrival sequence and importance, and the theoretical berthing and unberthing sequence is obtained, and the part of the berthing and unberthing sequence changed in the actual scheduling is punished to try to ensure the original berthing and unberthing sequence, and the specific explanation is as follows:

[0037]

[0038] Among them i1 ship berthing is completed after how many minutes i2 berthing (only considering the ship itself);

[0039] Among them i1 ship unberthing is completed after how many minutes i2 unberthing (only considering the ship itself);

[0040] Among them i1 ship berthing is completed after how many minutes i2 unberthing (only considering the ship itself);

[0041] Among them i1 ship unberthing is completed after how many minutes i2 berthing (only considering the ship itself);

[0042] For S3, the positive and negative deviation variables of the decision variables berthing time and unberthing time are defined, and soft constraint is made to ensure the feasibility and accuracy of the model, and the specific explanation is as follows:

[0043]

[0044] Flex_Ship_Arrivali For the elastic time constraint term, the elastic range of berthing time can be limited by controlling the value range of this term (setting the value of const)

[0045]

[0046] Flex_Ship_Leave i For the elastic time constraint term, the elastic range of berthing time can be limited by controlling the value range of this term (setting the value of const).

[0047] In the present application, the safety problem of ship-to-ship berthing and unberthing in the dock and channel in S5 does not include the moving process.

[0048] In the present application, the safety problem of ship-to-ship berthing and unberthing in the dock and channel in S5 does not include the moving process.

[0049] For S5, the specific explanation is as follows,

[0050] · Berthing and berthing: for i1, i2 two berthing ships, the berthing time should have a sequence and not conflict, at this time the assigned berth of each ship is known, wherein const 11 The term indicates that when i1 is assigned to k1 berthing and i2 is assigned to k2 berthing, the interval time needs to be satisfied and is a known quantity, and the specific value is stored in an external excel matrix.

[0051]

[0052]

[0053]

[0054] k1, k2 are known (k1 is the assigned berth of i1, and k2 is the assigned berth of i2)

[0055] · Unberthing and unberthing: for i1, i2 two unberthing ships, the unberthing time should have a sequence and not conflict, wherein const 12 The term indicates that when i1 is assigned to k1 unberthing and i2 is assigned to k2 unberthing, the interval time needs to be satisfied, and const 12 The term is a known quantity, and const 12 The specific value is stored in an external excel matrix.

[0056]

[0057]

[0058]

[0059] k1, k2 are known (k1 is i1 berthing position, k2 is i2 unberthing position)

[0060] Between berthing and unberthing: for any i1 berthing ship, i2 unberthing ship, their berthing and unberthing time should have a sequence and not conflict, where const 131 The term represents the interval time that needs to be met when i1 ship is assigned to k1 first berthing and i2 ship is assigned to k2 later unberthing, const 132 The term represents the interval time that needs to be met when i1 ship is assigned to k1 later berthing and i2 ship is assigned to k2 first unberthing, and here for the assignment of ship berthing position is known, so const 131 And const 132 are known constants stored in external excel matrix.

[0061]

[0062]

[0063] Unberthing, i2 unberthing, i1≠i2, non-moved ship

[0064]

[0065] Unberthing, i2 unberthing, i1≠i2, non-moved ship

[0066] k1, k2 are known (k1 is i1 berthing position, k2 is i2 unberthing position)

[0067] In S6, the tidal restriction is converted into a navigable time period, and the berthing and unberthing process is guaranteed to be completed within the navigable time period, and it is converted into a linear constraint, so as to guarantee the tidal restriction in the berthing and unberthing process, which is specifically explained as follows:

[0068] Berthing: for the i-th berthing ship, according to the tidal restriction, there are s1 segments of navigable time periods in a day, and the berthing time must be between the same segment of the s1 segments of navigable time periods. For the berthing time of each ship, only one of the s1 segments of navigable time periods contains the berthing time, and this s1 virtual variable represents the selection of which segment of the navigable time period, and only one segment takes 1, indicating that the berthing time is in the segment.

[0069]

[0070] Here, Let be the sailing time from the port to the berth when berthing. Berth allocation is already complete, and the berth assigned to each ship is known. Therefore, for a specific berth k, we iterate through its navigable time segment s1, and select a specific berthing navigable time segment using the following summation formula.

[0071]

[0072] • Departure: Mechanism is the same as berthing;

[0073]

[0074]

[0075] Here Let s be the sailing time from the berth to the gate when leaving the berth. Here, the berth allocation has been completed, and the berth allocated to each ship is known. Therefore, for a specific berth k, we traverse to find its s2 segment of navigable time, and select a specific segment of navigable time for departure by the following summation formula.

[0076] In this invention, S7 ensures that the tugboats have enough time to complete various plans through linear constraints. The constraints include the number of tugboats, the flexible time constraint that each tugboat works on one ship, and the constraint that the working times of multiple tugboats do not conflict with each other.

[0077] In this invention, the constraint that the working times of multiple tugboats do not conflict with each other includes that the operations of each tugboat do not conflict with those of different vessels.

[0078] Regarding the constraints in S7 that ensure tugboats have sufficient time to complete various plans through linear constraints, including constraints on the number of tugboats, flexible time constraints for each tugboat to work on one vessel, and constraints that prevent conflicts between the working times of multiple tugboats, the specific explanation is as follows:

[0079] Tug quantity constraints

[0080] Mooring:

[0081]

[0082] For the i-th ship, the number of tugboats required for berthing is less than or equal to the number of tugboats allocated to it.

[0083] Departure:

[0084]

[0085] For the i-th ship, the number of tugboats required for it to leave berth is less than or equal to the number of tugboats allocated to it.

[0086] In addition, to ensure that the number of tugboats assigned to each ship is as small as possible, an objective function is added for control.

[0087]

[0088] Flexibility time constraint for each tugboat working one ship.

[0089] • Start working time of tugboat at the berthing ship:

[0090] Time_tugboat_arrival_start ij

[0091] ≤ Time_ship_arrival i - const i + Flex_arrival_start ij

[0092] + M 51 (1 - Distribute_tugboat ij )

[0093] The above equation indicates that the start working time of the jth tugboat working the ith ship should be within a time period before the berthing of the ship, where const i represents how long before the berthing of the ith ship the tugboat needs to start working; Flex_arrival_start ij represents a flexible range for the start working time of the tugboat, which is determined by the following inequality:

[0094]

[0095] • End working time of tugboat at the berthing ship

[0096] The end working time of the jth tugboat working the ith ship should be around the berthing time of the ship, Flex_arrival_end ij represents the flexible time variable.

[0097] Time_tugboat_arrival_end ij

[0098] ≥ Time_ship_arrival i - Flex_arrival_end ij

[0099] - M 52 (1 - Distribute_tugboat ij )

[0100] Pv_separate ij≤Distribute_tugboat ij

[0101] Pv_separate ij is a dynamic virtual variable, which represents the number of tugboats that can be released in advance among the multiple tugboats assigned to the same ship, and Flex_arrival_end ij The variable only acts on the tugboats that can be released in advance, while the working end time of the tugboats that cannot be released in advance is consistent with the berthing time of the ship.

[0102]

[0103] The above formula indicates that at least two tugboats work until the end of the ship's berthing.

[0104]

[0105] The above formula indicates the flexible time range, and const is a constant set by a person.

[0106] · Start working time of the tugboat at the departure ship

[0107]

[0108] · End working time of the tugboat at the departure ship

[0109]

[0110]

[0111] The working times of multiple tugboats do not conflict with each other: each tugboat does not conflict between different ships;

[0112] · Between berthing and berthing: the jth tugboat can work on the next berthing ship after a certain interval after the completion of the work on the previous ship, where i1 and i2 represent different sequences.

[0113]

[0114]

[0115] i2 berthing and all require tugboats, and

[0116] where represents the interval time of the tugboat working between two ships, which is related to the berths of the previous and next ships.

[0117] Between the berthing and the berthing, the jth tugboat can work on the next berthing ship after a certain time interval after the previous ship's work is completed, and i1 and i2 represent different sequences of the first and second ships.

[0118]

[0119]

[0120] i2 berthing and both need a tugboat, and

[0121] wherein represents the time interval between the work of the tugboat between the two ships, which is related to the berths of the previous and next two ships;

[0122] Between the berthing and the berthing, the jth tugboat can work on the next berthing ship after a certain time interval after the previous ship's work is completed, and i1 and i2 represent different sequences of the first and second ships.

[0123]

[0124]

[0125] Berthing, i2 berthing and both need a tugboat,

[0126] wherein represents the time interval between the work of the tugboat between the two ships, which is related to the berths of the previous and next two ships;

[0127] In the present application, the moving process in S8 only affects the ships entering and leaving the harbor, and the safety problem caused by moving is transformed into the safety problem of ensuring the safety of any berthing and moving in the harbor, which is specifically explained as: any M ship berthing, N ship berthing, Q ship moving, the difference between the processes is that M ship berthing-Q ship moving, N ship berthing-Q ship moving; the above specific explanation is:

[0128] Between the berthing and the berthing

[0129] i1 ship is moved from k1 berth to other berths in the same harbor, i2 ship is berthed at k2 berth, when i1 ship leaves k1 berth and affects i2 ship berthing, c is the constant when i1 ship is moved.

[0130]

[0131]

[0132] Unberthing from k1 berth, berthing at i2, i1≠i2

[0133]

[0134] Unberthing from k1 berth, berthing at i2, i1≠i2

[0135] k1, k2 are known (k1 is i1 unberthing berth, k2 is i2 berthing berth)

[0136] Between berthing and unberthing

[0137] i1 ship is unberthing from other berth in the same basin, i2 ship is berthing at k2 berth, when i1 ship unberthing at k1 berth affects i2 ship berthing at k2 berth, the safety problem of i2 ship berthing and i1 ship unberthing needs to be considered, c is the constant of i1 ship unberthing.

[0138]

[0139]

[0140] Unberthing from k1 berth, berthing at i2, i1≠i2

[0141]

[0142] Unberthing from k1 berth, berthing at i2, i1≠i2

[0143] k1, k2 are known (k1 is i1 unberthing berth, k2 is i2 berthing berth)

[0144] Between berthing and unberthing

[0145] i1 ship is unberthing from other berth in the same basin, i2 ship is berthing at k2 berth, when i1 ship unberthing at k1 berth affects i2 ship berthing at k2 berth, the safety problem of i2 ship berthing and i1 ship unberthing needs to be considered, c is the constant of i1 ship unberthing.

[0146]

[0147]

[0148] Unberthing from k1 berth, berthing at i2, i1≠i2

[0149]

[0150] Unberthing from k1 berth, berthing at i2, i1≠i2

[0151] k1, k2 are known (k1 is the i1 moving berth, k2 is the i2 berth)

[0152] between the i2 berth and the i1 moving berth

[0153] The i1 ship is moved from other berths to the k1 berth in the same harbor basin, and the i2 ship is berthed from the k2 berth, and when the i1 ship affects the i2 ship to berth at the k2 berth due to the moving at the k1 berth, the safety problem of the i2 ship berthing and the i1 ship moving needs to be considered, and c is the i1 ship moving time.

[0154]

[0155]

[0156] The i1 ship is moved from other berths to the k1 berth, the i2 ship is berthed, and i1≠i2

[0157]

[0158] The i1 ship is moved from other berths to the k1 berth, the i2 ship is berthed, and i1≠i2

[0159] k1, k2 are known (k1 is the i1 moving berth, k2 is the i2 berth)

[0160] The present application, aiming at the safety problem of the berthing and unberthing of the ships in the harbor basin and the channel, converts the problem into the safety problem of the berthing and unberthing of any two ships in the harbor basin and the channel, then obtains the berthing and unberthing trajectories according to the ship information and the berthing berth, analyzes the influence between any two trajectories as the basic information, converts it into a linear constraint to ensure the safety in the navigation process, and through the creation of the port safety basic information library, efficiently and accurately expresses the mutual influence of the ships in the harbor basin and the channel during the berthing and unberthing process, can reasonably arrange the berthing and unberthing time of the ships, and improves the navigation efficiency.

[0161] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method for berthing and unberthing a single channel vessel, characterized in that, Based on ship loading and unloading plans, production operation conditions, and traffic organization rules, a mixed integer programming model is established to rationally plan ship berthing and departure schemes. The specific steps include: S1, based on the ship's size and navigation regulations, selects ships by characteristics, with priority levels set from 1 to 5, emphasizing the impact of the ship's own attributes on berthing and departure; S2, establish the order penalty matrix to obtain the theoretical berthing and departure order from the order of ship arrival and priority; S3 defines positive and negative deviation variables for the decision variables berthing time and departure time, and applies soft constraints to ensure the feasibility and accuracy of the model. S4: Based on the influence range of different constraints, find the optimal calculation range, divide the berths of different harbor basins, reduce the number of calculations per ship, and improve the calculation speed. S5 addresses the safety requirements for berthing and unberthing between vessels in the harbor basin and waterway. Based on vessel information and berthing positions, it obtains berthing and unberthing navigation trajectories, comprehensively analyzes the correlation between any two navigation trajectories, and transforms them into constraints to ensure safety during navigation. It also improves the speed of the algorithm by converting the constraints that would otherwise be extensively written in the program into a harbor basin constraint data table, which significantly reduces the program's redundancy and the number of constraint loops within the program. S6. Select three Hermite interpolations for tide level processing to obtain a minute-by-minute tide level table for the entire time period. Transform the impact of tidal changes into navigable time periods. Iterate through and extract each segment of the start and end time points of each ship as planning time windows. Ensure that the berthing and departure processes are completed within the navigable time periods and transform them into linear constraints to ensure the berthing and departure processes meet the tide requirements. S7. Based on the relationship between the number of tugboats used, the start time and the berthing and departure time during the berthing and departure processes of each ship, the start and end times of tugboat use for each ship are obtained. Considering the sailing time of tugboats between any two berthing and departure dynamics, linear constraints are used to ensure that tugboats efficiently complete various plans, thereby ensuring the berthing and departure plans meet the needs of tugboat use. S8. The shifting process only affects the entry and exit of ships in the harbor basin. The safety issues caused by shifting are transformed into safety assurance issues in the waters affected by shifting. Based on the ship information and the berthing and shifting berths, the ship's navigation trajectory is obtained. The correlation between any two navigation trajectories is analyzed as basic information and transformed into linear constraints to ensure the safety of navigation. S9, constructing the objective function according to the above constraints, , The weights of the ship berthing time, unberthing time and the length of the berthing operation in the target formula are controlled respectively; The relationship between the constraint condition and the target function is established for controlling the virtual variable of each constraint term; The tugboat usage time is controlled, and the allocation and usage efficiency of the tugboat in the same period is maximized; represents the total number of ships participating in the berthing and unberthing scheduling; represents the berthing waiting time of the i-th ship; represents the unberthing waiting time of the i-th ship; represents the berthing operation time of the i-th ship; represents the unberthing operation time of the i-th ship; represents the berthing operation time of the i-th ship; represents the unberthing operation time of the i-th ship; , , The three are weight coefficients, respectively. This indicates the total number of tugboats participating in the dispatch; for each tugboat... , For the usage time of each tugboat, For tugboats Usage time weighting coefficient; The model is solved with the objective of minimizing waiting time for vessels in port and maximizing berth utilization.

2. The method according to claim 1, wherein, The mixed integer programming model is solved using the Gurobi optimizer.

3. The method of claim 1, wherein, The safety issues concerning berthing and unberthing between ships in the harbor basin and waterway mentioned in S5 do not include the shifting berth process.

4. The method of claim 1, wherein, The safety issues arising from shifting berths are transformed into issues concerning the safety assurance within the waters affected by shifting berths; specifically, for any two vessels A and B, the process is as follows: vessel A berths - vessel B berths, vessel A berths - vessel B departs, vessel A departs - vessel B berths, vessel A departs - vessel B departs.

5. The method of claim 1, wherein, The linear constraint in S7 ensures that the tugboat has sufficient time to complete the constraints in the plan, including the number of tugboats, the flexible time constraint of each tugboat working on a ship, and the non-conflict constraint of the working time of multiple tugboats.

6. The method of claim 5, wherein, The non-conflict constraint of the working time of multiple tugboats includes the non-conflict between each tugboat operation on different ships.

7. The method of claim 1, wherein, In S8, the moving process only affects the ships entering and leaving the port in the harbor, and the safety problem caused by the moving is converted into the safety guarantee problem in the water area affected by the moving. Specifically, for any M ships berthing, N ships unberthing, and Q ships moving, the process is different, that is, M ships berthing-Q ships moving, and N ships unberthing-Q ships moving.

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