Method for route planning for marine vessels in a confined space

Abstract

This invention provides a computer implementation method for generating routes in waterways for the automatic control of marine vessels. [Solution] A computer implementation method for generating a route P in a channel 40 for the automatic control of an ocean vessel 10, comprising: acquiring position data of the ocean vessel; determining, based on the position data, that the ocean vessel is approaching or in the channel; identifying the starboard portion of the channel relative to the position of the ocean vessel from geographic map data; determining a collision-free route in the starboard portion 52 of the channel while moving through the channel; and providing an output of the determined collision-free route for the automatic control of the ocean vessel along the determined collision-free route.

Description

[Technical Field]

[0001] The present invention generally relates to a computer implementation method for generating a waterway route for an offshore vessel, a control unit for performing the method, an offshore vessel equipped with the control unit, and a corresponding computer program product. [Background technology]

[0002] Route planning algorithms play a crucial role in optimizing performance and ensuring the successful execution of missions for marine vessels. These algorithms are responsible for generating positional trajectories and speed profiles while considering various constraints, such as propulsion capabilities and obstacles in the sea. Navigation in restricted waters, such as narrow waterways and shipping lanes, presents additional significant challenges due to limited space and the need to comply with maritime safety regulations.

[0003] However, current route planning methods for marine vessels often focus on optimizing operational efficiency, such as reducing travel time and minimizing energy consumption. This can lead to unsafe trajectories, particularly when vessels are turning in narrow passages where they might take "shortcuts" to reduce distance, potentially resulting in violations of navigation rules. [Overview of the Initiative]

[0004] In consideration of the aforementioned and other drawbacks of the prior art, the object of the present invention is to provide a method for route planning in waterways for marine vessels that at least partially mitigates the drawbacks of the prior art.

[0005] According to a first aspect of the present invention, a computer implementation method for generating a route in a waterway for the automatic control of an ocean vessel is provided, the method comprising: acquiring position data of an ocean vessel; determining, based on the position data, that the ocean vessel is approaching or in a waterway; identifying the starboard portion of the waterway relative to the position of the ocean vessel from geographic map data; determining a collision-free route in the starboard portion of the waterway while moving through the waterway; and providing an output of the determined collision-free route for the automatic control of the ocean vessel along the determined collision-free route.

[0006] This invention is at least in part based on realizing the incorporation of requirements in route planning for ocean vessels to maintain on the starboard side of channels. This is particularly important in confined spaces and even more so when there are bends in the route with confined space. Conventional route planning methods take shortcuts to save time and energy, which increases the risk of collision. The method proposed herein keeps the vessel on the correct side of the route at all times while providing a collision-free route.

[0007] The safety of ocean maritime navigation has been improved by mandating compliance with the so-called COLREG (International Convention for the Prevention of Collisions at Sea) Rule 9, which specifies the requirements that ocean maritime vessels must maintain on their starboard side.

[0008] This method may involve controlling the thrusters of an ocean vessel to move along a predetermined collision-free path through a waterway.

[0009] In an embodiment, the method may comprise determining from geographical map data that the width of a waterway is less than a predetermined threshold and, in response thereto, identifying a right - hand side portion. In other words, it is first determined whether the waterway is a narrow waterway where the method is most efficient. That is, only when the waterway is sufficiently narrow does the method proceed with the identification of the right - hand side portion of the waterway and subsequent steps. Further, a marine vessel may dynamically recognize when strict navigation rules (such as Rule 9) must be applied. By automatically detecting narrow waterways, the method enables a marine vessel to adjust its route - planning behavior without manual input, ensuring safe and efficient navigation in a constrained space. Further, an automated mechanism for evaluating the waterway width is incorporated into the vessel.

[0010] In an embodiment, the right - hand side portion of the waterway may be a section that is half of the width of the waterway. In other words, the right - hand side of half of the waterway width is considered the right - hand side of the waterway. This provides maximum space and flexibility in a collision - free route that saves travel time and energy consumption. In other embodiments, the right - hand side portion is less than half of the width to provide a buffer distance up to the remaining half where a secondary vessel can move.

[0011] In an implementation form, determining a collision - free route may comprise determining a collision - free route that optimizes at least the travel time and energy consumption of the route in the waterway. Advantageously, the required fuel can be reduced, providing a more environmentally friendly operation of the marine vessel. Further, this improves the efficiency of the marine vessel and reduces the fuel usage and transit time while maintaining compliance with navigation rules, such as staying on the right - hand side.

[0012] In an embodiment, the collision - free route may be determined based on an objective function that optimizes at least the travel time and energy consumption of the route in the waterway. Using an objective function provides optimizing the collision - free route while balancing various parameters such as travel time and energy consumption.

[0013] Preferably, the objective function minimizes at least the travel time and energy consumption of the route through the waterway while adhering to requirements that must be maintained on the starboard side while moving through the waterway.

[0014] In this embodiment, the objective function can further minimize the speed changes of the offshore vessel in the waterway. Reducing speed changes is one way to reduce energy consumption and also reduce wear and tear on the offshore vessel. Furthermore, a more stable speed provides safer operation in confined spaces.

[0015] In embodiments, the method may comprise determining an initial collision-free path through a waterway that conforms to requirements to be maintained on the starboard side while moving through the waterway, the collision-free path being an improved collision-free path determined based on the initial collision-free path and an objective function. In this way, a relatively accurate starting path is provided to the objective function, thereby providing a more computationally efficient determination of the improved collision-free path. The optimization problem is configured to minimize factors such as travel time, energy consumption, and velocity changes. Using the initial collision-free path determined as the starting point can improve confidence that the generated improved path is not only safe but also optimized for efficiency and performance.

[0016] In this embodiment, the initial collision-free path is generated in accordance with COLREG Rule 9, using a graph search algorithm and a library of predefined feasible movements that the ocean vessel can execute. The use of this predefined movement library enables rapid determination of the initial path, ensuring safe and compliant navigation. This library allows for the rapid calculation of feasible paths, which is particularly beneficial for real-time operations where quick decision-making is crucial for autonomous or semi-autonomous vessels. The use of graph search improves computational efficiency by systematically evaluating the best path options, reducing the time required for decision-making. The predefined feasible movements of the ocean vessel ensure that only reasonable and feasible collision-free paths are generated.

[0017] In some embodiments, the method may include dynamically adjusting the collision-free path based on real-time environmental data, including wind conditions and ocean currents, while maintaining compliance with COLREG Rule 9.

[0018] Preferably, this method can be carried out continuously while the offshore vessel is in operation.

[0019] This method can be performed autonomously for at least partially autonomous ocean vessels.

[0020] According to a second aspect of the present invention, a control unit is provided which is configured to perform the steps described in any one of the embodiments of the first aspect.

[0021] Further effects and features of the second aspect of the present invention are largely similar to those described above in relation to the first aspect of the present invention.

[0022] Further marine vessels equipped with control units will be provided.

[0023] According to a third aspect of the present invention, a computer program product is provided for performing the method described herein, when executed by a control unit.

[0024] The computer program product includes program code for acquiring positional data of an ocean vessel, determining whether the ocean vessel is approaching or in a waterway based on the positional data, identifying the starboard portion of the waterway relative to the ocean vessel's position from geographic map data, determining a collision-free path through the starboard portion of the waterway while the vessel is moving through it, and providing an output of the determined collision-free path for the automatic control of the ocean vessel along the determined collision-free path.

[0025] Further effects and features of the third aspect of the present invention are largely similar to those described above in relation to the first and second aspects of the present invention.

[0026] Further features and advantages of the present invention will become apparent upon consideration of the appended claims and the following description. Those skilled in the art will recognize that different features of the present invention can be combined to create embodiments other than those described below, without departing from the scope of the invention.

[0027] These and other aspects of the present invention will now be described in more detail with reference to the accompanying drawings illustrating exemplary embodiments of the present invention. [Brief explanation of the drawing]

[0028] [Figure 1] A schematic example of an offshore vessel according to an embodiment of the present invention is provided below. [Figure 2A] This is a flowchart of the method steps according to an embodiment of the present invention. [Figure 2B] This is a flowchart of the method steps according to an embodiment of the present invention. [Figure 3] A schematic example of an offshore vessel in a waterway according to an embodiment of the present invention is provided below. [Figure 4] A schematic example of an offshore vessel having a port side and a starboard side according to an embodiment of the present invention is provided. [Modes for carrying out the invention]

[0029] In embodiments for carrying out the present invention, various embodiments of the invention are described herein with reference to specific implementations. Certain technical terms are used for clarity when describing embodiments. However, the present invention is not intended to be limited to such selected technical terms. Certain illustrative embodiments are discussed, but it should be understood that these are for illustrative purposes only. Those skilled in the art will recognize that other components and configurations may be used without departing from the scope of the present invention.

[0030] Figure 1 schematically shows a top view of an offshore vessel 10. The offshore vessel 10 may be, for example, a ship or a floating production, storage, and offloading (FPSO) unit. The vessel 10 comprises a number of thrusters, in this case a first thruster 12a, a second thruster 12b, a third thruster 12c, and a fourth thruster 12d. One, some, or all of the thrusters 12a-12d may also be referred to by the reference numeral "12".

[0031] Each thruster 12 is rotatable in different thrust directions within a horizontal plane (parallel to the drawing plane in Figure 1). Each thruster 12 may comprise a propeller and an engine that drives the propeller. The thrust of the thruster 12 can be increased by increasing the engine speed of the engine, and vice versa. Although the thruster 12 is illustrated here as an azimuth thruster, the present invention is not limited thereto.

[0032] The vessel 10 further comprises a control system 14. In this example, the control system 14 comprises a control unit 16 and a memory 18. The memory 18 stores a computer program 20. The computer program 20 comprises program code that, when executed by the control unit 16, causes a data processing device or the control unit 16 to perform or instruct it to perform various steps described herein.

[0033] As shown in Figure 1, a model 21 of the vessel 10 can be stored in memory 18. The model 21 may be, for example, a nonlinear model of the vessel 10 that describes the motion of the vessel 10 in a horizontal plane.

[0034] The vessel 10 in this example further comprises one or more sensors, exemplified here as a position sensor 22. The position sensor 22 is configured to provide position data 24 to a control system 14. The position data 24 indicates the position of the vessel 10 in a horizontal plane. The position sensor 22 may be, for example, a GPS device that further provides map data to the control system 14.

[0035] The vessel 10 may further include at least one sensor 26 for detecting objects near the offshore vessel. These objects may be secondary vessels, harbor structures, islands, or other objects that could obstruct the travel path for the offshore vessel 10. The at least one sensor 26 may be a radar, lidar, or similar sensor capable of providing object data 28 about nearby objects to a control unit 16.

[0036] The control system 14 can also receive position data 24 or data about surrounding objects from the remote control center 36 or the server 36.

[0037] Furthermore, the control unit 16 has access to geographic map data 23 stored in memory 18. The geographic map data 23 includes nautical charts and may also be accessible from the remote server 36.

[0038] When operating the ocean vessel 10 along a route, the control system 14 controls the thrusters 12 to propel the ocean vessel from a first position to a second position. When moving along a route in a constrained space such as a narrow waterway, it is desirable to find a safe route that can avoid collisions with obstacles and provide optimized energy consumption. In narrow waterways, especially when turning in narrow waterways, it is important to find a trade-off between finding the most efficient route and simultaneously minimizing collisions with other vessels. To address this, embodiments of this specification propose generating a waterway route for ocean vessels that complies with COLREG Rule 9 by imposing the stringent requirement that the generated collision-free route lies in the starboard portion of the waterway.

[0039] Figures 2A and 2B are flowcharts of the method steps according to embodiments of the present invention. Figure 3 schematically illustrates an ocean vessel 10 moving along a route in a waterway. Figures 2A and 2B and Figure 3 are described together.

[0040] An ocean vessel 10 is moving through a channel 40. The channel 40 has a width w between neighboring structures 50a, 50b or land parcels.

[0041] The ocean vessel is moving further along the channel in one direction 42. Ahead of the ocean vessel 10 is a secondary ocean vessel 44 moving along the channel 40 in direction 46. The secondary ocean vessel 44 has almost reached a bend in the channel 48 and is approaching the host ocean vessel 10.

[0042] The ocean vessel 10 utilizes a computer implementation method to generate a route P in the waterway 40 for the automatic control of the ocean vessel 10.

[0043] In step S102, the control unit 16 acquires position data 24 for the ocean vessel 10. In step S104, the control unit 16 determines that the ocean vessel 10 is in the waterway 40 by comparing the position data with geographic map data 23.

[0044] In some embodiments, the control unit 16 evaluates the waterway width to determine whether the waterway is classified as narrow. Based on this, in step S105, the control unit determines from geographic map data whether the width w of the waterway 40 is less than a predetermined threshold. If affirmative, the method proceeds to step S106. If negative, the method restarts from step S102.

[0045] A narrow waterway is typically considered a body of water where the width of the waterway limits a vessel's ability to maneuver, requiring it to follow a defined route to avoid grounding or collision. The designation of a narrow waterway can vary depending on factors such as the size and draft of vessels using the waterway, and the presence of navigational hazards. Therefore, the width of a narrow waterway is context-dependent and defined by the local maritime authority or the navigational characteristics of the area.

[0046] In step S106, the control unit 16 identifies the starboard portion 52 of the channel relative to the position of the ocean vessel 10 from the geographic map data 23. The starboard portion 52 is at most half the width w of the channel. In this example, the starboard portion 52 of the channel is a section that is approximately half the width w of the channel. That is, the starboard portion 52 is about half the width w of the channel.

[0047] In step S108, the control unit 16 determines a collision-free path P in the starboard section 52 of the channel 40 while moving along it. The requirement here is to maintain the starboard section 52 throughout the entire path P. This requirement is in accordance with COLREG Rule 9.

[0048] In step S110, the control unit 16 provides an output 60 of the determined collision-free path P. The output data 60 is used by the control system 14 for automatic control of the propulsion of the ocean vessel 10 along the generated path. The output data 60 may include, for example, control signals for controlling the thrusters of the propulsion system so that the generated path P can be followed.

[0049] The control unit may be further configured to control the ocean vessel to move along the generated path P, preferably without human intervention or with only minimal human intervention.

[0050] Determining a collision-free path P involves determining a collision-free path that optimizes at least the travel time and energy consumption of path P in the channel 40, while still adhering to maintaining the starboard side 52.

[0051] Finding such a route P can be achieved using an objective function 62 stored in memory 18, which optimizes at least the travel time and energy consumption of the route through the waterway while adhering to the requirements to be maintained on the starboard side while moving through the waterway. In some embodiments, the objective function further minimizes the speed change of the offshore vessel 10 in the waterway 40.

[0052] Determining a path P can be achieved in various ways other than using an objective function. One possible methodology for generating path P is to utilize techniques such as rule-based methods. These rely on predefined rules and heuristics to derive a path plan without formal optimization. Another possibility is to use machine learning techniques such as reinforcement learning, where the system learns the optimal path through trial and error rather than explicitly optimizing a mathematical function. Additionally, multi-objective optimization can be used, allowing for a more flexible approach that balances multiple performance criteria simultaneously rather than optimizing a single objective function. Other exemplary algorithms include genetic algorithms, convolutional neural networks, or recurrent neural networks, to give a few further examples.

[0053] Here, as an example, an optimization problem for generating a path P that utilizes the objective function is described.

[0054] The objective function includes several terms to ensure time optimality, integration of Rule 9 into the path plan, and energy optimality. The optimization problem is formulated as follows:

[0055]

number

[0056] In an optimization problem, OP1 represents an objective function that includes several terms:

[0057] t f This is the duration of control.

[0058] s r9 This is a slack variable corresponding to the integration in Rule 9.

[0059] q r9This is a weight in the objective function that controls the importance of adhering to Rule 9 compared to other terms in the objective function. It represents a trade-off between optimizing for time / energy and maintaining the distance of waterway 40 from the centerline 64 as specified by Rule 9.

[0060] ||F|| 2 This term represents the force required to be generated by thrusters 12a-d. This term facilitates the finding of the optimal energy solution.

[0061] q F This is a weight that imposes a penalty on the force generated by thrusters 12a to d.

[0062]

number

[0063] This term represents the rate of change of force generated by thrusters 12a-d. This term encourages less aggressive and smoother use of the thrusters.

[0064]

number

[0065] This is a weight that imposes a penalty on the rate of change of thruster force.

[0066] ||F|| 2 This term can be replaced with an energy cost metric such as the mechanical energy consumed by the ocean vessel 10 or the electrical energy used by the propulsion system.

[0067] The decision variables for the optimization problem include the position and velocity trajectories for maneuvering the ocean vessel 10, the forces and torques required to follow these trajectories, and the duration of the maneuvering task.

[0068] In the optimization problem, OP2 represents constraints corresponding to the kinematic and kinetic equations of the ocean vessel 10. These constraints ensure that the path generated by solving the optimization problem follows the equations of motion of the ocean vessel 10, thereby guaranteeing dynamic feasibility. In equation (OP2),

[0069]

number

[0070] This diagram illustrates the position and orientation of a vessel represented by a fixed Earth frame, where x and y are the north and east distances from the NED (North, East, and Down coordinate) origin to the vessel's center of gravity, respectively, and φ is the bow azimuth angle. The velocity vector of vessel 10 is:

[0071]

number

[0072] This is illustrated by the following, where u is the fixed velocity of the object in surge (along the longitudinal axis of the ship), v is the fixed velocity of the object in sway (across that axis), and r is the fixed velocity of the object in yaw rate (angular velocity). The rotation matrix R(φ) is given by the following:

[0073]

number

[0074] In equation (OP2), M is the body inertia matrix, which is the sum of the rigid body mass and the hydrodynamically added mass. The C(ν) matrix includes nonlinear terms resulting from the Coriolis effect and centripetal effect. The matrix D(ν) includes the hydrodynamic damping force or drag force.

[0075]

number

[0076] captures the total forces and moments due to thrusters 12a - d, where F x , F y , and M r are the forces and torques acting on surge, sway, and yaw dynamics, respectively. ω is the rate of change of the force generated by the ship's thrusters. [[ID=八]]

[0077] The inequality constraints OP3 and OP4 correspond to the capabilities of the propulsion system of the marine vessel 10. These constraints impose limits on the forces and torques generated by the thrusters of the marine vessel 10 and also on the rate at which the forces generated by each thruster can change. The matrix A τ , B, b τ in (OP3) are calculated based on the positions of the thrusters of the marine vessel 10 and the thruster limitations regarding the magnitude and direction of the forces that the thrusters can generate.

[0078] The equality constraints (OP5) and (OP6) represent the state of the marine vessel 10 when the optimization problem is being solved. These constraints ensure that the optimization problem is initialized with the current position and velocity of the marine vessel 10 and enable the marine vessel 10 to smoothly follow the generated path without sudden maneuvers.

[0079] The inequality constraint OP7 is used to incorporate consistency with Rule 9. In this constraint, s r9 ∈ [0, d ch represents a slack variable,

[0080]

Number

[0081] is the bow azimuth angle at the k - th sample point of the initial path, and d ch (k) is half of the channel width at that particular sample point. This value is calculated as follows.

[0082]

Number

[0083] Here, dS k and dP k These represent the location of the ocean vessel 10 corresponding to the k-th sample of the initial path, and the minimum distance between it and obstacles located on the starboard and port sides, respectively. The denominator of the above equation acts as a soft switch, effectively distinguishing between narrow channels and wider areas. By adding this new inequality to the optimization problem, the optimization algorithm can handle the slack variable s. r9 The effort is directed towards minimizing it, and a value close to zero is sought. This adjustment is at least 0.5 (dS), which is equal to half the width of the channel, from any obstacles located on the port side. k +dP k It is converted into an orbit that maintains the distance between s and s. r9 ga d ch When equal to d, the algorithm can freely use the entire area of ​​the local polygon as needed. The new geometric interpretation of the safety inequality is that all points in the area around the ocean vessel 10 are d ch (k)-s r9 This means that it is shifted by a distance in the opposite direction to the port side. This transformation is a unit vector that points to the port side.

[0084]

number

[0085] This is consistent with matrix A. s , b s This is calculated based on the locations of both stationary and moving obstacles around the ocean vessel 10. These matrices define collision-free polygons, which can then be used by the algorithm to find a safe path. In these two inequalities, c rot (φ) is the rotation matrix from the object frame to the Earth frame, and is given by the following:

[0086]

number

[0087] In some embodiments illustrated in the flowchart of Figure 2B, step S108a comprises a control unit 16 determining an initial collision-free path through the waterway that conforms to the requirements to be maintained on the starboard side while moving through the waterway. The collision-free path is determined in step S108b as an improved collision-free path determined based on the initial collision-free path and the objective function.

[0088] The initial collision-free path is generated in accordance with COLREG rule 9, using a graph search algorithm and a library 70 of predefined feasible movements that the ocean vessel can execute. The library 70 may be stored in onboard memory 18 or accessible from a remote server 36. Here, using the library 70 of predefined feasible movements is illustrated in more detail with reference to Figure 4, purely as an example.

[0089] Figure 4 schematically illustrates an ocean vessel 10. Motion primitives are predefined, which are feasible movements that the ocean vessel 10 can perform. Motion primitives represent a comprehensive set of actions that the ocean vessel 10 can use to navigate from one state to another, including straight-line movement, changes in heading, speed adjustment, and other basic maneuvers. Using motion primitives ensures computational efficiency and kinematic feasibility of the initial path without violating any constraints on the capabilities of the ocean vessel 10.

[0090] To incorporate Rule 9 into the initial solution generation phase, a specific term is added to the cost function of the graph search algorithm. This term is defined as follows:

[0091]

number

[0092] This equation contains several important variables. Firstly, N p This represents the horizontal length of the motion primitive selected by the algorithm in each iteration. Also, W nc This is the width threshold for identifying a water pipe as narrow. In addition to this, dS i and dP i is the minimum distance between the location of the ocean vessel 10 corresponding to the i-th sample of the motion primitive and the obstacles located on the starboard and port sides, respectively. Some important points regarding this equation are as follows:

[0093] If the position of the ocean vessel 10 in the i-th sample is closer to the obstacle on the starboard side, dS i <dP i And then, J come This implies that the second term in the equation becomes zero. In this case, the trajectory is consistent with rule 9, and therefore no additional penalty is imposed on the selected motion primitive. Conversely, when the position of the ocean vessel 10 in the i-th sample is closer to the port side obstacle, dS i >dP i The following holds true. As a result, dS i and dP i The cost increases in proportion to the difference between the two. In other words, as the trajectory approaches the port-side obstacle, the associated cost of that selection through the algorithm also increases.

[0094]

number

[0095] The denominator given by acts as a soft switch to activate the newly introduced term associated with Rule 9. Specifically, the quantity (dS i +dP i ) represents the width w of the waterway 40 at the i-th sample point. This indicates that the ocean vessel 10 is located outside the narrow waterway (dS i +dP i )≫Wnc In this case, the denominator takes a remarkably large value. From this, J come The second clause within it is substantially reduced, meaning that Rule 9 is not considered. Conversely,

[0096]

number

[0097] In this case, the denominator is close to 1. Therefore, the term consistent with rule 9 is J come It contributes to this.

[0098] Stationary obstacles are represented as polygons, each described by a set of linear equations. This characterization allows for the efficient calculation of the distance from a point to each stationary obstacle. However, the problem arises of how to distinguish between obstacles on the port side and obstacles on the starboard side. To address this, the equation of a straight line 80 passing through the center of gravity of the ship 10 at an inclination equal to the bow azimuth angle is determined. Point A, located on the port side at a distance Δd from the center of gravity, is calculated as follows:

[0099]

number

[0100] A straight line is, f(x,y) = ax + by + c It is expressed as f(x A ,y A The sign of f(x) plays an important role in determining the relationship between the point and the ocean vessel 10. For example, consider a point like point B in Figure 4, f(x B ,y B The sign of f(x A ,y A If the sign of f(x) coincides with that of f(x), then point B is also located on the port side. Conversely, f(x) C ,y C The sign of f(x A ,y A When the sign is opposite to that of (), points such as point C in Figure 4 are classified as being on the starboard side.

[0101] The method described herein can be performed autonomously by a control unit 16 for at least a partially autonomous offshore vessel 10.

[0102] The method described herein generates routes for the automatic control of a vessel and, optionally, optimizes both travel time and energy efficiency. It not only mimics the actions of a skilled human operator but also improves performance criteria such as time and energy. However, unlike a human operator, the control unit can calculate the entire route P for the current maneuvering task from start to finish in a single step.

[0103] The computer program product 20 includes program code for performing the method described herein, which includes at least code for acquiring position data of an ocean vessel; code for determining, based on the position data, that the ocean vessel is approaching or in a waterway; code for identifying the starboard portion of the waterway relative to the position of the ocean vessel from geographic map data; code for determining a collision-free path through the starboard portion of the waterway while moving through the waterway; and code for providing an output of the determined collision-free path.

[0104] The control unit may include a microprocessor, microcontroller, programmable digital signal processor, or other programmable device. The control unit may also, or instead, include an application-specific integrated circuit, a programmable gate array or programmable array logic, a programmable logic device, or a digital signal processor. If the control unit includes a programmable device such as the aforementioned microprocessor, microcontroller, or programmable digital signal processor, the processor may further include computer executable code that controls the operation of the programmable device.

[0105] In one or more examples, the described functions may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, these functions may be stored as one or more instructions or codes on a computer-readable medium, or transmitted through a computer-readable medium and executed by a hardware-based processing unit. The computer-readable medium may include computer-readable storage media corresponding to tangible media such as data storage media, or communication media including any medium that facilitates the transfer of computer programs from one location to another, for example, according to a communication protocol. Thus, the computer-readable medium may generally correspond to (1) non-transient tangible computer-readable storage media, or (2) communication media such as signals or carrier waves. The data storage medium may be any available medium that can be accessed by one or more computers or one or more processors to retrieve instructions, codes and / or data structures for implementing the techniques described herein. A computer program product may include computer-readable media.

[0106] Such computer-readable storage media may include, but are not limited to, RAM, ROM, EEPROM®, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, flash memory, or any other media that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.

[0107] While the present invention has been described with reference to its specific illustrative embodiments, many different variations, modifications, and similarities will become apparent to those skilled in the art.

[0108] In addition, variations of the disclosed embodiments can be understood and achieved by those skilled in the art when carrying out the claimed invention, based on a review of the drawings, disclosures, and appended claims. In the claims, the word “equips” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude the plural. The mere fact that certain means are described in different dependent claims does not imply that combinations of these means cannot be used advantageously.

Claims

1. A computer implementation method for generating a route (P) in a waterway (40) for the automatic control of an ocean vessel (10), wherein the method is: To acquire position data (24) for the aforementioned ocean vessel (S102), Based on the position data, it is determined that the ocean vessel is approaching or in the waterway (S104), From geographic map data (23), the starboard portion of the channel relative to the position of the ocean vessel is identified (S106), While moving through the waterway, determine a collision-free path in the starboard portion (52) of the waterway (S108), To provide an output (60) of the determined collision-free path for the automatic control of the marine vessel along the determined collision-free path (S110) A method that includes [a certain feature].

2. Based on the aforementioned geographic map data, it is determined that the width (w) of the waterway is less than a predetermined threshold (S105), and in response, the starboard portion is identified. The method according to claim 1, comprising:

3. The method according to claim 1 or 2, wherein the starboard portion of the waterway is a section that is half the width of the waterway.

4. The method according to any one of claims 1 to 3, wherein the requirement to be maintained in the aforementioned starboard portion is COLREG Rule 9.

5. The method according to any one of claims 1 to 4, wherein determining the collision-free path comprises determining the collision-free path that optimizes at least the travel time and energy consumption of the path in the water supply.

6. The method according to claim 5, wherein the collision-free path is determined based on an objective function that optimizes at least the travel time and energy consumption of the path in the waterway.

7. The method according to claim 5 or 6, wherein the objective function minimizes at least the travel time and energy consumption of the path in the waterway while complying with the requirements to be maintained in the starboard portion while moving in the waterway.

8. The method according to any one of claims 5 to 7, wherein the objective function minimizes the change in speed of the offshore vessel in the waterway.

9. The system comprises determining an initial collision-free path in the waterway that conforms to requirements to be maintained on the starboard side while moving through the waterway, wherein the collision-free path is an improved collision-free path determined based on the initial collision-free path and the objective function. The method according to any one of claims 5 to 8.

10. The method according to claim 9, wherein the initial collision-free path conforms to COLREG rule 9 and is generated using a graph search algorithm and a library of predefined feasible movements that the ocean vessel can perform.

11. The method according to any one of claims 1 to 10, comprising dynamically adjusting the collision-free path based on real-time environmental data, including wind conditions and ocean currents, while maintaining compliance with COLREG Rule 9.

12. The method according to any one of claims 1 to 11, wherein the method is performed autonomously for at least a partially autonomous ocean vessel.

13. A control unit (16) configured to perform the method described in any one of claims 1 to 12.

14. An offshore vessel comprising the control unit described in claim 13.

15. A computer program product (20) comprising program code for performing the method according to any one of claims 1 to 12 when executed by a control unit.

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