Route planning system and route planning method

Abstract

Provided are a device and a method for assisting in safe navigation while avoiding collision between a moving body such as a ship and an obstacle such as another ship. The present invention is provided with: a planned route acquisition unit that acquires planned route information indicating a planned route of a moving body; a moving body information acquisition unit that acquires moving body information including a position and a moving direction of the moving body; an obstacle information acquisition unit that acquires obstacle information including a position and a movement direction for each of the plurality of obstacles; a collision risk value calculation unit that calculates a collision risk value on the basis of the moving body information and the obstacle information; a maximum collision risk obstacle selection unit that selects a maximum collision risk obstacle corresponding to the maximum collision risk value from among the obstacles; a congestion risk value calculation unit that calculates a congestion risk value indicating the degree of simultaneous approaching for one or more obstacles including / excluding the obstacle having the maximum collision risk; and a risk evaluation unit that determines, on the basis of the congestion risk value, that the vehicle travels along a route that is different from the planned route.

Description

Technical Field

[0001] The present invention relates to a ship navigation system mainly used to enable a ship to navigate safely, and more specifically, to a route planning system and a route planning method for avoiding collision with these obstacles and thus enabling the ship to navigate safely even when there are multiple obstacles around the ship. Background Art

[0002] Usually, before a ship or other mobile body starts sailing, a navigation plan route (route) is set from the departure point or starting point to the destination. Currently, in order to make the mobile body move safely, a navigation system and device for generating and monitoring the planned route are sometimes placed on the mobile body such as a ship.

[0003] In these existing route planning systems, in order to avoid collisions with other ships or other obstacles, the position of the mobile object such as the ship itself and the positions of nearby obstacles and other ships on the planned route are detected and identified, and multiple sensor units are used for tracking to obtain mobile object information and obstacle information.

[0004] Patent document 1: US2020 / 0310434

[0005] However, during navigation on a planned route, the planned route may need to be changed due to human factors such as nearby obstacles or other ships crossing the planned route. In addition, due to natural factors such as rapid changes in ocean conditions, tides and other external disturbances, the route may need to be changed from the planned route. Summary of the invention

[0006] Therefore, the ship driver (operator) needs to avoid collision with surrounding obstacles and other ships and navigate the mobile body such as the ship safely along the planned route. In addition, it is sometimes necessary to assist navigation in the state of the ocean or the tide.

[0007] The problem to be solved by the present invention is to provide a system, device and method for assisting a ship driver to navigate a mobile body safely by avoiding collisions with multiple obstacles and other ships in accordance with the above needs.

[0008] The route planning system of the present invention comprises: a planned route acquisition unit, which acquires planned route information indicating a planned route of a mobile body moving on water; a mobile body information acquisition unit, which acquires mobile body information including the position and moving direction of the mobile body; and an obstacle information acquisition unit, which acquires obstacle information including the position and moving direction for each of a plurality of obstacles existing around the mobile body. In addition, the system comprises: a collision risk value calculation unit, which calculates a collision risk value indicating the risk degree of collision between the mobile body and each obstacle based on the mobile body information and the obstacle information; a congestion risk value calculation unit, which calculates a congestion risk value indicating the degree of simultaneous approach of obstacles included in the congestion risk obstacle based on the collision risk value corresponding to each obstacle included in the congestion risk obstacle for a congestion risk obstacle including a plurality of the obstacles; and a risk evaluation unit, which determines whether the mobile body needs to navigate on an avoidance route having a route different from the planned route based on the congestion risk value.

[0009] The moving object information also includes the moving speed of the moving object, and the obstacle information may also include the moving speed of the obstacle, which can be calculated based on the position and orientation detected at a predetermined period.

[0010] Here, the risk assessment unit includes: a congestion risk assessment unit that compares the congestion risk threshold set for the congestion risk value with the congestion risk value, outputs a congestion risk assessment result, and can also decide whether it is necessary to navigate on an avoidance path based on the congestion risk assessment result.

[0011] In addition, the route planning system of the present invention further comprises: a maximum collision risk obstacle selection unit, which selects a maximum collision risk obstacle corresponding to a maximum collision risk value from among the obstacles. The risk assessment unit further comprises: a maximum collision risk assessment unit, which compares a collision risk threshold set for the maximum collision risk value with the maximum collision risk value, and outputs a maximum collision risk assessment result. It is also possible to decide whether it is necessary to navigate on an avoidance path based on the congestion risk assessment result and the maximum collision risk assessment result.

[0012] The route planning system of the present invention further comprises: an avoidance route setting unit which sets an avoidance route different from the planned route for a part or all of the untraveled route of the mobile body in the planned route when the risk assessment unit determines that the avoidance route needs to be set.

[0013] Here, the avoidance path setting unit may also include: an avoidance path candidate plan generating unit, which generates one or more avoidance path candidate plans that are different from the planned route between the avoidance starting point on the unnavigated route and the planned route return point as candidates for the avoidance path; and an avoidance path selecting unit, which selects an avoidance path from the avoidance path candidate plans.

[0014] In the route planning system of the present invention, the congestion risk value calculation unit may also calculate the congestion risk value of the planned route based on the value of the logical sum of multiple collision risk values ​​including the maximum collision risk value among the multiple collision risk values. Alternatively, the congestion risk value of the planned route may also be calculated based on the value of the logical sum of multiple collision risk values ​​excluding the maximum collision risk value among the multiple collision risk values.

[0015] In addition, the congestion risk value calculation unit may also calculate the congestion risk value based on the collision risk values ​​corresponding to the selected plurality of obstacles among the plurality of obstacles corresponding to the obstacle information acquired by the obstacle information acquisition unit. The congestion risk value calculation unit may also calculate the congestion risk value based on the collision risk value corresponding to each obstacle in the quasi-maximum collision risk obstacle group, wherein the quasi-maximum collision risk obstacle group includes a quasi-maximum collision risk obstacle corresponding to a quasi-maximum collision risk value that is the second largest collision risk value after the maximum collision risk value, and an obstacle having a collision risk value smaller than the quasi-maximum collision risk value.

[0016] In the route planning system of the present invention, the congestion risk value calculation unit calculates the congestion risk value of the planned route and the congestion risk value of the avoidance path based on the value of the logical sum of the plurality of collision risk values.

[0017] Here, the collision risk value calculation unit calculates the maximum collision risk value for each of the one or more avoidance route candidate solutions, and the congestion risk calculation unit calculates the congestion risk value for each of the one or more avoidance route candidate solutions.

[0018] In addition, the collision risk value calculation unit calculates the maximum collision risk value of the mobile body when navigating according to each of the avoidance path candidate plans, and the avoidance path selection unit selects the avoidance path candidate plan whose maximum collision risk value is below a specified threshold as the avoidance path. The avoidance path selection unit has an avoidance path navigation determination unit, which determines whether the maximum collision risk value corresponding to the selected avoidance path is less than the maximum collision risk value for the planned route, and if so, determines that it is necessary to navigate on the avoidance path.

[0019] Here, the congestion risk value calculation unit calculates the congestion risk value of the avoidance route when the mobile body navigates the selected avoidance route, and the avoidance route selection unit further determines that it is necessary to navigate the selected avoidance route when the congestion risk value of the avoidance route is smaller than the congestion risk value for the planned route.

[0020] The avoidance route selection unit may further consider, for each of the avoidance route candidate plans, the distance that the mobile body has traveled along each of the avoidance route candidate plans, and determine whether avoidance is necessary.

[0021] The avoidance route selection unit may select, as the avoidance route, a candidate navigation route having a minimum navigation distance for the mobile body among the candidate navigation routes for which both the maximum collision risk value and the congestion risk value are less than or equal to a predetermined threshold value.

[0022] In the route planning system of the present invention, the obstacle information can include at least one of the following information: information detected by at least one of radar, LIDAR, SONAR, and image sensors installed on the mobile body; information received by an automatic identification system receiver; information sent by other ships other than the mobile body; information detected by wireless communication at a location other than the mobile body. In addition, the obstacle information may also include at least one of other ships, tidal currents, weather, reefs, and stranded ships.

[0023] The route planning system of the present invention may also include: a display that displays the avoidance path together with the planned route on the display image. Furthermore, it may also include: a route planning unit that provides one or more routes for the navigation of the mobile body from the departure point to the destination; and one or more sensor units that obtain obstacle information.

[0024] The route planning method of the present invention obtains planned route information representing a planned route of a mobile body moving on water, obtains mobile body information including the position, moving direction and moving speed of the mobile body, obtains obstacle information including the position, moving direction and moving speed for each of multiple obstacles existing around the mobile body, calculates a collision risk value representing the risk level of collision between the mobile body and each obstacle based on the mobile body information and the obstacle information, selects a maximum collision risk obstacle corresponding to the maximum collision risk value from among the obstacles, and for a congestion risk obstacle including one or more obstacles including the maximum collision risk obstacle, calculates a congestion risk value representing the degree of simultaneous approach of obstacles included in the congestion risk obstacle based on the collision risk value corresponding to each of the obstacles included in the congestion risk obstacle, and determines whether the mobile body needs to navigate on an avoidance path having a path different from the planned route based on the congestion risk value.

[0025] Here, whether to navigate on the avoidance path may also be determined by comparing a congestion risk threshold value set for the congestion risk value with the congestion risk value. In addition, whether to navigate on the avoidance path may also be determined by comparing a collision risk threshold value set for the maximum collision risk value with the maximum collision risk value.

[0026] In the route planning method of the present invention, when it is determined that an avoidance route needs to be set, an avoidance route different from the planned route may be set for a part or all of the untraveled route of the mobile body in the planned route.

[0027] Furthermore, one or more alternative avoidance path plans that are different from the planned route and are candidates for the avoidance path may be generated between the avoidance start point on the untraveled route and the planned route return point, and the avoidance path may be selected from the alternative avoidance path plans. In addition, the congestion risk value of the planned route may be calculated based on the value of the logical sum of multiple collision risk values ​​excluding the maximum collision risk value among the multiple collision risk values.

[0028] In the route planning system of the present invention, a maximum collision risk value is calculated for each of one or more alternative flight avoidance paths, and a congestion risk value may also be calculated for each of one or more alternative flight avoidance paths.

[0029] It is also possible to calculate, for each of the alternative avoidance path plans, the maximum collision risk value of the mobile body when navigating according to the alternative avoidance path plan, select the alternative avoidance path plan with the maximum collision risk value below a specified threshold as the avoidance path, and determine whether the maximum collision risk value corresponding to the selected avoidance path is less than the maximum collision risk value for the planned route. If so, it is determined that it is necessary to navigate on the avoidance path.

[0030] Among the avoidance route candidate plans whose maximum collision risk value and congestion risk value are both below a predetermined threshold value, the avoidance route candidate plan having the shortest navigation distance of the mobile body may be selected as the avoidance route.

[0031] The route planning program of the present invention is a computer-executable program, and the computer executes the following steps:

[0032] acquiring planned route information indicating a planned route of a mobile body moving on water,

[0033] Obtaining information about the moving object including its position, moving direction and moving speed,

[0034] Obstacle information including position, moving direction and moving speed is obtained for each of a plurality of obstacles existing around the moving object.

[0035] Based on the moving object information and the obstacle information, a collision risk value indicating the risk level of collision between the moving object and each obstacle is calculated.

[0036] The maximum collision risk obstacle corresponding to the maximum collision risk value is selected from the obstacles.

[0037] For a congestion risk obstacle including one or more obstacles including the maximum collision risk obstacle, a congestion risk value indicating the degree to which the obstacles included in the congestion risk obstacle are simultaneously approached is calculated based on the collision risk value corresponding to each of the obstacles included in the congestion risk obstacle,

[0038] Based on the congestion risk value, it is determined whether the mobile body needs to navigate on an avoidance path having a path different from the planned route.

[0039] In this specification, although the terms "risk value" such as "collision risk value" and "congestion risk value" are described, it may be a risk degree obtained by quantifying the risk based on a prescribed rule. The "collision risk value" is a value obtained by quantifying the degree of possibility of collision with an obstacle (ship) with a risk of collision based on a prescribed criterion, and the "congestion risk value" is a value obtained by quantifying the degree of possibility of collision with any one of the multiple obstacles when there are multiple obstacles with a risk of collision based on a prescribed criterion.

[0040] The planned route is not limited to the entire route from the departure point to the destination, and can be a route before the current position of the mobile body that has already set sail and is navigating in the planned route, or a planned route before the predicted position that will be passed in the future. In addition, an avoidance path for the mobile body can be generated instead of the planned route and applied here instead of the planned route.

[0041] Congestion risk is a concept that represents the degree to which obstacles included in the congestion risk obstacles are approaching at the same time based on the collision risk value corresponding to each of the multiple obstacles that may become congestion risks. As an example, the congestion risk value of the planned route is calculated based on the multiple collision risk values ​​ranging from 0 indicating a state without congestion risk to 1 indicating a congestion risk equivalent to a maximum collision risk value indicating the maximum collision risk among the obstacles. Here, the range of the congestion risk value is represented by a numerical range of 0 to 1, but is not limited to this.

[0042] Furthermore, the congestion risk value of the avoidance path is also determined. The congestion risk value calculation unit calculates the congestion risk values ​​of the planned route and the avoidance path based on multiple collision risk values ​​other than the maximum collision risk value among the multiple collision risk values. As an example of calculation of the congestion risk value based on multiple collision risk values ​​other than the maximum collision risk value, the value of the logical sum of each collision risk value that is the object of calculation is calculated and is set as the congestion risk value. However, the calculation based on the logical sum is only an example, and is not simply based on the logical sum, but is not limited to the above example as long as it represents a numerical value corresponding to the degree of simultaneous approach to obstacles, such as multiplying a high coefficient in the case of high collision risk.

[0043] This is also described in detail in the specific implementation. However, whether the obstacle with the maximum risk value is included in the objects of congestion risk value calculation or excluded from the objects of congestion risk value calculation has its own significance, and either method can be adopted.

[0044] The present invention solves the problem that in the past, when multiple obstacles could not be detected on the planned route, a navigation avoidance path is generated based on the current position of the moving body and the position ahead of the predicted position, so that the ship driver can intuitively use realistic visual information for safe navigation.

[0045] Furthermore, according to the route planning system of the present invention, the ship driver can navigate a mobile object such as the ship safely by avoiding collisions with multiple surrounding obstacles such as ships and terrain, using the avoidance path displayed on the image on the display unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The embodiments illustrated by way of technical means for solving the technical problem can be understood by referring to the accompanying drawings. Here, similar parts are represented by the same reference numerals as a whole. The following description is only one embodiment, representing a specific selected embodiment of a system, device and method consistent with the claimed problem and the technical means for solving the problem.

[0047] Figure 1 This is a block diagram showing the configuration of a route planning system for safely navigating a mobile object moving on water by operating the own ship or the like, which is one embodiment of the route planning system of the present invention.

[0048] Figure 2 This is a diagram for explaining one embodiment, and is a diagram showing the positional relationship between the own ship and other ships in an area surrounding the own ship.

[0049] Figure 3 This is a diagram for explaining one embodiment, and is a diagram showing the positional relationship between the own ship and other ships in the area surrounding the own ship. Here, although the own ship is on the planned route, it is facing in a direction inclined with respect to the course.

[0050] Figure 4 This is a block diagram showing the structure of a route planning system for safely navigating a mobile object moving on water by operating the own ship or the like, which is another embodiment of the route planning system of the present invention.

[0051] Figure 5 This is a diagram showing an example of a risk assessment unit and a configuration related thereto in one embodiment of the route planning system of the present invention.

[0052] Figure 6 The present invention is a diagram showing one embodiment of a route planning system of the present invention, which determines collision risk values ​​associated with obstacles along a planned route.

[0053] Figure 7This is a diagram showing one embodiment of the route planning system of the present invention, which determines the collision risk value when the own ship approaches an obstacle.

[0054] Figure 8 The relationship between the time until the host ship and the obstacle reach the closest distance and the collision risk value is shown for explaining one embodiment.

[0055] Fig. 9 This is a diagram showing another embodiment of the route planning system of the present invention, which determines the collision risk value when the own ship approaches an obstacle.

[0056] Fig.10 This is a diagram showing still another embodiment of the route planning system of the present invention, which determines the collision risk value when the own ship approaches an obstacle.

[0057] Fig.11 This is a block diagram of a route planning system for safely navigating a moving object (or own ship) according to still another embodiment of the route planning system of the present invention.

[0058] Fig.12 This is a block diagram of a route planning system for safely navigating a moving object (or own ship) according to still another embodiment of the route planning system of the present invention.

[0059] Fig.13 This is a diagram showing an example of the configuration of an avoidance route setting unit in the route planning system of the present invention.

[0060] Fig.14 This is a diagram showing an example of generating a candidate avoidance route in the route planning system of the present invention.

[0061] Fig.15 This is a diagram for explaining one embodiment, and shows an avoidance path of the own ship that is set when the own ship (mobile object) follows the avoidance path.

[0062] Fig.16 This is a part of a flowchart showing a route planning method according to an embodiment of the present invention.

[0063] Fig.17 yes Fig.16 A portion of a flowchart follows the flowchart shown.

[0064] Description of Reference Numerals

[0065] 1Route planning device

[0066] 2Route Planning Department

[0067] 3. GNSS receivers

[0068] 4 One or more sensor parts

[0069] 5Navigation Control Department

[0070] 6Display unit (display)

[0071] 11Plan route acquisition department

[0072] 12Mobile body information acquisition unit

[0073] 13Obstacle Information Acquisition Unit

[0074] 14Collision risk (danger level) calculation unit

[0075] 15Congestion risk (danger level) calculation department

[0076] 16Risk Assessment Department

[0077] 17 Avoidance Path Setting Unit

[0078] 18 Maximum collision risk value selection section

[0079] 19Congestion Risk Assessment Department

[0080] 20 Maximum Collision Risk Assessment Department

[0081] 21 Avoidance Path Selection Unit

[0082] 22 Avoidance route alternative plan generation unit

[0083] 100 Route Planning System

[0084] 200 Mobile object (own ship)

[0085] 202 planned route

[0086] 204, 206, 902, 904 obstacles

[0087] 212 Avoidance Path

[0088] 302, 304, 306, 308, 310, 312 Congestion risk objects and obstacles

[0089] 1102 Avoidance Path Alternative Plan

[0090] WP1 Avoidance start point (from planned route to avoidance path)

[0091] WP4 Return point (from the avoidance path, etc. to the planned route) DETAILED DESCRIPTION

[0092] Here, an embodiment of the route planning system of the present invention is described by way of example. Other exemplified embodiments or features may be further utilized, and other changes may be made without departing from the spirit or scope of the subject matter presented in this specification.

[0093] The exemplary embodiments described in this specification are not limited. The embodiments of the present invention can be arranged, replaced, combined, separated, and designed in various different structures as shown in the drawings generally described in this specification, all of which can be easily understood in this specification.

[0094] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof.

[0095] Figure 1 This is a block diagram showing the configuration of a route planning system 100 for safely navigating a moving object 200 according to an embodiment of the present invention. Figure 2 and Figure 3 This is a predetermined area around the own ship 200, which represents one embodiment of the route planning system of the present invention. Hereinafter, the moving object 200 is also referred to as the own ship 200 as appropriate.

[0096] The route planning system 100 can be installed on the ship 200 itself and is used to navigate the ship 200 from the departure point to the destination. When the voyage starts, the route planning system 100 monitors whether the ship 200 is accurately navigating along the planned route 202 that the ship 200 should follow between the departure point and the destination.

[0097] The route planning system 100 is used to enable the ship 200 to navigate safely without colliding with ships identified as obstacles, adverse sea conditions or weather, and surrounding obstacles that are other obstacles. The ship driver, i.e., the operator driving the ship 200, receives assistance from the route planning system 100 to navigate the ship 200 along the planned route 202.

[0098] like Figure 2 and Figure 3 As shown, in this embodiment, the planned route 202 is a route that should be followed in order for the ship 200 to navigate and arrive at the destination safely. The planned route 202 shows the route of the ship 200 and the heading direction from the current position of the ship 200.

[0099] The route planning unit 2 is configured to store a plurality of routes for the navigation of the ship 200. In the present embodiment, in order to perform various functions according to the functions of the route planning system, the ship driver can operate various peripheral devices operably connected to the route planning system 100. For example, the user can provide the route planning system 1 with various instructions regarding the location of the departure point and the destination of the navigation of the ship 200 by operating peripheral devices such as a keyboard and a mouse.

[0100] The route planning unit 2 can provide one or more routes for the navigation of the ship 200 from the departure point to the destination based on the information such as the location and destination of the source of the message acquired from the user. In this embodiment, each route can include the date and time of the navigation, weather conditions, tidal conditions, etc., and can be associated with such information.

[0101] The route planning unit 2 receives user input from the ship driver or related personnel as a path selection of the planned route 202 used in the navigation of the ship 200 from the departure point to the destination. In the present embodiment, the ship driver selects the path to be moved, but as another embodiment, the route planning unit 2 itself may select the best path based on the current weather conditions, travel time, tide or current conditions, etc.

[0102] The route planning system 1 uses information related to other moving bodies 200 such as other ships and multiple obstacles 204 and 206 in the area around the ship 200 in order to safely navigate the ship 200 along the planned route 202 from the departure point to the destination. A global navigation satellite system (GNSS) receiver 3 is generally installed on the ship 200 to obtain moving body information such as the position, moving direction, and speed of the ship 200. The GNSS receiver 3 receives satellite signals and accurately obtains the above-mentioned moving body information related to the ship 200.

[0103] One or more sensor units 4 obtain obstacle information including position, moving direction, and speed of multiple obstacles 204, 206 that may hinder the navigation of the ship 200. The sensor unit 4 may also correspond to one or more marine electronic equipment. As a specific structure of the sensor unit 4, it may be a wireless detection ranging (RADAR) device, a light detection ranging (LIDAR) device, an acoustic navigation ranging (SONAR) device, an automatic identification system (AIS) receiver, a camera or a video recorder mounted on the ship 200, and other image sensors with detection or detection functions. The sensor unit 4 only needs to be able to detect obstacles to the navigation of the ship 200, and is not limited to the above, and is not limited to sensors installed on the ship, and may also be based on information sent from other ships, land management agencies, etc.

[0104] In this embodiment, obstacle information includes: information detected by any one or at least one of radar, LIDAR device, SONAR device, image sensor, information acquired by an AIS receiver, information sent from other ships, and information acquired by wireless communication detection at locations outside the ship 200.

[0105] In this embodiment, for ease of understanding, there are only two obstacles 204 and 206 along the planned route 202, but the number of obstacles is not limited to two and may be more than two. In other embodiments, the obstacles that are planned to cross or approach the planned route 202 or have such a tendency may also include any number of obstacles more than two without departing from the scope of the present invention.

[0106] In this embodiment, the obstacle information also includes information related to other moving objects including at least one of other ships, tides, weather, reefs, and stranded ships. The information related to other moving objects can be obtained by the same method as that of obtaining the information of the plurality of obstacles 204 and 206.

[0107] like Figure 1 As shown, the route planning system 1 includes a planned route acquisition unit 11, a mobile body information acquisition unit 12, an obstacle information acquisition unit 13, a collision risk value calculation unit 14, a congestion risk value calculation unit 15, and a risk assessment unit 16. Figure 1 In addition, refer to Figure 2 and Figure 3 Provide explanation.

[0108] The planned route acquisition unit 11 can be operatively connected to the route planning unit 2 for receiving the planned route selected by the ship driver as the planned route 202. The mobile body information acquisition unit 12 can be operatively connected to the GNSS receiver 3 for receiving mobile body information associated with the ship 200. Furthermore, the mobile body information acquisition unit 12 is configured to store the received mobile body information.

[0109] The obstacle information acquisition unit 13 is used to receive obstacle information associated with multiple obstacles 204, 206, and can be operably connected to and communicate with one or more sensor units 4. The obstacle information acquisition unit 13 is configured to receive obstacle information, which includes the position, moving direction, and speed of each obstacle of the multiple obstacles 204, 206 that cross the planned route passed by the ship 200 or approach the planned route detected by the sensor unit 4. In this embodiment, the planned route is the planned route 202 that the ship 200 is scheduled to sail. The obstacle information acquisition unit 13 is also configured to store the above-mentioned obstacle information.

[0110] In the present embodiment, the moving body information acquisition unit 12 periodically acquires the moving body information of the host ship 200 , and the obstacle information acquisition unit 13 periodically acquires the obstacle information of the plurality of obstacles 204 and 206 .

[0111] The collision risk value calculation unit 14 can be operably connected to the planned route acquisition unit 11, the mobile body information acquisition unit 12, and the obstacle information acquisition unit 13 and communicate with them respectively. The collision risk value calculation unit 14 receives the planned route 202 as the route of the scheduled navigation, the mobile body information of the own ship 200, and the obstacle information of the plurality of obstacles 204 and 206, and calculates the risk value of the collision with the own ship 200 in numerical form based on these. The specific calculation of the collision risk value and the congestion risk value will be described later.

[0112] The collision risk value calculation unit 14 is further configured to calculate a plurality of collision risk values ​​for a plurality of obstacles 204, 206 that are expected to be located on the planned route 202 based on the moving body information and the obstacle information. The plurality of collision risk values ​​may be calculated based on the positions, moving directions, and speeds of the ship 200 and the plurality of obstacles 204, 206. The plurality of collision risk values ​​represent risk values ​​of collision between the ship 200 and the plurality of obstacles 204, 206.

[0113] In this embodiment, when obstacles 204 and obstacle 206 are navigating along predicted future paths 208 and 210 respectively, and the ship 200 continues to navigate along the planned route, the predicted future paths 208 and 210 and the planned route of the ship 200 interfere with each other at the points shown in the figure, and there is a possibility of collision.

[0114] exist Figure 2 and Figure 3 In the case shown, if the multiple collision risk values ​​associated with the planned route are high, the collision risk between the ship 200 and the multiple obstacles 204 and 206 becomes high. Figures 6 to 10 The determination of the collision risk value associated with obstacle 204 will be described in detail.

[0115] return Figure 1 The congestion risk value calculation unit 15 is configured to be operably connected to the collision risk value calculation unit, communicate with the collision risk value calculation unit 14, and receive a plurality of collision risk values ​​related to the plurality of obstacles 204 and 206 along the planned route 202. Further, here, the congestion risk value calculation unit 15 is configured to determine the congestion risk value associated with the planned route 202 along the current path direction based on the plurality of collision risk values. The congestion risk value indicates the degree of simultaneous approach of the obstacles included in the risk obstacles located in the congested area based on the collision risk values ​​corresponding to the obstacles included in the risk obstacles located in the congested area.

[0116] The congestion risk value calculation unit 15 determines the congestion risk value corresponding to the planned route 202 based on the value of the logical sum of the plurality of collision risk values, as an example of calculation corresponding to the plurality of obstacles 204 and 206. In the present embodiment, the congestion risk value calculation unit 15 obtains the congestion risk value of the planned route 202 based on the value of the logical sum of the plurality of collision risk values ​​excluding the maximum collision risk value among the plurality of collision risk values.

[0117] The "logical sum" mentioned here means that when one or both of the two propositions mentioned in the logical operation are true, the result is true; when both are false, the result is false. In other words, it is based on the logic that the logical sum of the two inputs based on the logic circuit or binary value is 1 when one or both of them are 1, and 0 when both are 0. For example, suppose there are four obstacles Obs(1), Obs(2), Obs(3), and Obs(4), and the collision risk values ​​are 0.3, 0.5, 0.7, and 0.9 respectively. The maximum collision risk value is 0.9 for Obs(4), and the logical sum of the other three obstacles Obs(1) to Obs(3) is 0.7.

[0118] Figure 4 This is a block diagram showing the structure of a route planning system for safely navigating a mobile object moving on water by operating the own ship or the like, which is another embodiment of the route planning system of the present invention. Figure 1 The difference is that in Figure 4 In the illustrated embodiment, a maximum collision risk value selection unit 18 is provided.

[0119] The maximum collision risk value selection unit 18 selects an obstacle having the largest collision risk value, i.e., an obstacle having the highest collision risk, from the collision risk values ​​for each of the plurality of obstacles calculated by the collision risk value calculation unit 14. In the present embodiment, as described above, the possibility of collision must be evaluated with the highest priority for the obstacle having the largest collision risk value, and avoidance action is taken as necessary.

[0120] On the other hand, for obstacles other than the obstacle with the maximum collision risk, the collision risk caused by the degree of simultaneous approach, that is, the congestion risk, is evaluated. To perform this processing, for a set of one or more obstacles having collision risk values ​​other than the maximum collision risk value, the congestion risk value calculation unit 15 inputs these collision risk values ​​and calculates the congestion risk value.

[0121] In addition, in the present embodiment, the collision risk with the obstacle having the maximum collision risk value is evaluated separately, so it can be excluded, but it can also be included. In addition, when excluding the obstacle having the maximum collision risk value to calculate the congestion risk value, including the obstacle having the quasi-maximum risk value after the maximum risk value to calculate the congestion risk value can more accurately calculate the congestion risk value.

[0122] However, in the evaluation of collision risk, it is preferred to calculate the congestion risk value based on the respective collision risk values ​​of one or more other obstacles after excluding the obstacle with the maximum collision risk value, and evaluate the maximum collision risk value and the congestion collision risk value separately. This is because the top priority should be given to avoiding collision with the obstacle with the maximum collision risk value. Then, when taking collision avoidance action, other collision risks are considered, such as the collision risk with obstacles including the obstacle with the quasi-maximum collision risk value having the second highest collision risk value. However, the maximum collision risk value may also be included in the calculation of the congestion risk value.

[0123] Figure 5 The maximum obstacle risk value selected by the maximum collision risk value selection unit 18 is directly evaluated by the maximum collision risk evaluation unit 20 in the risk evaluation unit 16 by comparing it with a predetermined maximum collision risk threshold value.

[0124] On the other hand, collision risk values ​​other than the maximum collision risk value are input to the congestion risk value calculation unit 15 to calculate the congestion risk value, which is then compared with a predetermined congestion risk threshold value in the congestion risk assessment unit 19 of the risk assessment unit 16 for risk assessment.

[0125] In this embodiment, if both the maximum collision risk value and the congestion risk value are below their respective prescribed thresholds, the risk assessment unit 16 determines that there is no collision risk and outputs the risk assessment result. Even if one exceeds the threshold, it is determined that there is a collision risk. However, if the maximum collision risk value is lower than the threshold, even if the congestion risk value exceeds the threshold, it can be determined that the emergency collision risk is small.

[0126] As described above, the risk assessment unit 16 and the congestion risk value calculation unit 15 can work in conjunction to obtain the congestion risk value associated with the planned route 202. The risk assessment unit 16 also determines whether the ship 200 should avoid the planned route 202 or continue to sail along the planned route 202 based on the congestion risk value associated with the planned route 202. The potential collision risk can be determined by evaluating the congestion risk value of the planned route 202. When the congestion risk value is high, the ship 200 avoids the planned route 202 and sails on other routes such as the avoidance path 212 to avoid collisions with multiple obstacles 204 and 206.

[0127] In this embodiment, when the risk assessment unit 16 determines that the ship 200 needs to avoid the planned route 202 based on the congestion risk value, Figure 2 and Figure 3 As shown, the route planning system 1 urges the ship driver to navigate the ship 200 from the current position of the ship 200 or the predicted position of the ship's future navigation, i.e., these reference points (or heading points) 214 as starting points, along the avoidance route 212. This can be assumed to be various means such as warning display on the image, sound, etc.

[0128] In this embodiment, the scheduled route that the ship 200 should navigate when it is sailing according to the planned route 202 is the planned route 202, but those skilled in the art will appreciate that the scope of the present invention is not limited thereto. As another embodiment, the route that the ship 200 should navigate when it follows the avoidance path 212 can be assumed to be the avoidance path 212 without departing from the scope of the present invention.

[0129] As another embodiment, when the ship 200 is sailing along the avoidance path 212, the collision risk value calculation unit 14 calculates multiple collision risk values ​​associated with multiple obstacles 204, 206 along the avoidance path 212 (a path predetermined for avoidance) based on the moving body information and the obstacle information.

[0130] The congestion risk value calculation unit 15 calculates the congestion risk value associated with the avoidance path 212 based on the plurality of collision risk values. For example, as described above, the congestion risk value calculation unit 15 calculates the congestion risk value corresponding to the avoidance path 212 based on the value of the logical sum of the plurality of collision risk values ​​corresponding to the plurality of obstacles 204 and 206. In the present embodiment, the congestion risk value calculation unit 15 determines the congestion risk value of the avoidance path 212 based on the value of the logical sum of the plurality of collision risk values ​​excluding the maximum collision risk value among the plurality of collision risk values.

[0131] The risk assessment unit 16 determines whether the ship 200 should deviate from the avoidance path 212 or continue to sail on the avoidance path 212 based on the congestion risk value associated with the avoidance path 212. The route planning system 1 repeatedly performs collision avoidance processing with multiple obstacles 204 and 206 along the planned route that the ship 200 passes, that is, the planned route 202 or the avoidance path 212, and recalculates and resets the avoidance path when the risk of collision on the planned route is high.

[0132] Reference Figure 1 , Figure 2 as well as Figure 3 The navigation control unit 5 may also be operably connected to and communicate with the risk assessment unit 16. The navigation control unit 5 is configured to monitor and control the navigation of the own ship 200 based on the judgment of whether the own ship 200 deviates from and avoids the planned route 202 or the avoidance path 212 set to avoid obstacles, or continues to navigate along the planned route 202 or the avoidance path 212.

[0133] The navigation control unit 5 may deviate from and avoid the avoidance route 212 temporarily set to avoid an obstacle. This is because it is assumed that another obstacle approaches while navigating along the avoidance route 212 and further avoidance is required.

[0134] In order to control the navigation of the ship 200, the navigation control unit 5 can control the position, movement direction, and speed of the ship 200. Based on the judgment that the ship 200 avoids the planned route 202 or the avoidance path 212, the navigation control unit 5 sometimes makes the ship 200 navigate along the avoidance path 212 or the planned route 202, an avoidance path different from the original avoidance path 212, and the like.

[0135] As an example, based on the actual sailing direction of the ship 200, such as Figure 2 As shown, the current navigation direction of the ship 200 is along the planned route 202. As another example, based on the actual navigation direction of the ship 200, as shown in FIG. Figure 3 As shown, the current sailing direction of the own ship 200 is along the avoidance path 212 .

[0136] The display unit 6 is a ship instrument for a purpose described later, and is mounted on the ship 200 or is electrically connected to the risk assessment unit 16 mounted on the ship 200. The display unit 6 displays a planned route 202 that the ship 200 should follow.

[0137] When the ship 200 avoids the planned route 202, the display unit 6 displays the avoidance route 212 for avoiding collision with the plurality of obstacles 204 and 206 that the ship 200 navigates. In addition, when the ship 200 deviates from and avoids the avoidance route 212, the display unit 6 displays another avoidance route for avoiding collision with the plurality of obstacles 204 and 206 that the ship 200 navigates. Thus, the ship operator can avoid collision with the plurality of obstacles 204 and 206, and can navigate the ship 200 safely.

[0138] Figure 6 The present invention shows a case where a collision risk value associated with an obstacle 204 along a planned route is determined in accordance with an embodiment of the route planning system of the present invention. The collision risk value calculation unit 14 calculates a collision risk value for the obstacle 204 based on the moving body information and the obstacle information. Here, the collision risk value for the obstacle 204 is determined based on the position, moving direction, and speed of the ship 200 and the obstacle 204.

[0139] The collision risk value calculation unit 14 is configured to also calculate the closest distance Dc between the ship 200 and the obstacle 204, and both or one of the closest distances Dx and Dy in a specific direction based on the moving body information and the obstacle information. In the present embodiment, the closest distance Dc is the distance between the current position of the ship 200 and the closest point 302. In the figure, the closest distance Dx in the vertical direction (for example, the direction of navigation when viewed from the ship 200) is the distance between the current position of the ship 200 and the closest point 304 in the vertical direction.

[0140] The closest distance Dy in the direction perpendicular to the vertical direction (here, the horizontal direction is referred to as the lateral direction relative to the sailing direction of the ship) is the distance between the current position of the ship 200 and the closest point 306 in the horizontal direction. The collision risk value calculation unit 14 calculates the closest distances Dc, Dx, and Dy when the ship 200 approaches the obstacle 204 based on the positional relationship between the ship 200 and the obstacle 204, the relative speed between the ship 200 and the obstacle 204, and the moving direction and speed of the ship 200 and the obstacle 204.

[0141] The collision risk value calculation unit 14 obtains a collision risk value of the obstacle 204 based on at least one of the closest distance Dc between the host ship 200 and the obstacle 204 and the closest distances Dx and Dy in a specific direction.

[0142] In this embodiment, when the closest distance Dc is less than the prescribed distance and the risk assessment unit 16 determines that the collision risk is high, the ship 200 needs to avoid the obstacle 204. In this case, the ship 200 deviates from the planned route 202 and sails along a different path, that is, the set avoidance path 212. On the other hand, when the closest distance Dc is greater than the prescribed distance, the risk assessment unit 16 determines that the collision risk is low, and the ship 200 can continue to sail on the planned route 202.

[0143] In another embodiment, when the closest distance Dx or Dy in a specific direction is less than a specified distance and the risk assessment unit 16 determines that the collision risk is high, the ship 200 needs to avoid the planned route and sail on another path, that is, the avoidance path to avoid the obstacle 204. On the other hand, when the closest distance in the specific direction Dx and Dy is greater than the specified distance, the risk assessment unit 16 determines that the collision risk is low, in which case the ship 200 may continue to sail on the planned route.

[0144] In this embodiment, the collision risk value can also be calculated by determining the positional relationship between the ship 200 and the obstacle 204 based on both or either of the closest distance Dx in the vertical direction and the closest distance Dy in the horizontal direction. Generally speaking, when the obstacle 204 crosses the front of the ship 200, the risk of collision between the ship 200 and the obstacle 204 becomes higher.

[0145] In the present embodiment, the collision risk value calculation unit 14 is configured to further determine the time Tc required for the own ship 200 to cross the closest distance Dc. The collision risk value calculation unit 14 further calculates the collision risk value of the obstacle 204 when the own ship 200 sails from the starting point (e.g., departure point) of the planned route 202 toward the destination, based on the closest distance Dc and the time Tc required for the other ship that becomes the obstacle 204 to reach the closest distance 302. The time Tc required for the other ship to reach the closest distance 302 is calculated based on the moving body information and the obstacle information.

[0146] If the collision risk value is calculated based on the closest distance Dc between the own ship 200 and the obstacle 204, the collision risk value will increase even if the time until the own ship 200 approaches the obstacle 204 is very long. As a result, the own ship 200 may have to deviate from the planned route in order to avoid a collision with the obstacle 204 after a period of time. Therefore, in this embodiment, the collision risk value associated with the obstacle 204 is determined by considering the closest distance Dc between the own ship 200 and the obstacle 204 and the time Tc required for the own ship 200 to reach the closest point 302.

[0147] As an example, the collision risk value for the obstacle 204 is calculated and determined based on the following formula (1).

[0148] Collision risk value=max(Dx,Dy)×RT c (1)

[0149] Figure 7 The present invention shows a scenario of determining the collision risk value when the own ship 200 approaches the obstacle 204 in one embodiment of the route planning system of the present invention. When the obstacle 204 enters the elliptical area 402 centered on the own ship 200, the collision risk value becomes higher. Here, as an example, the elliptical area 402 is determined based on the area within 1.5 NM (nautical miles) in front, 0.2 NM in the back, and 0.5 NM on the side of the own ship 200. The collision risk value increases as the distance between the own ship 200 and the obstacle 204 decreases.

[0150] Therefore, the collision risk value is inversely proportional to the distance between the host ship 200 and the obstacle 204 .

[0151] Figure 7 The relationship between the collision risk value and the vertical distance between the ship 200 and the obstacle 204, and the relationship between the collision risk value and the horizontal distance between the ship 200 and the obstacle 204 are also shown. Figure 7 The collision risk values ​​of the closest contact distances Dx and Dy in the vertical direction and the horizontal direction are shown in FIG.

[0152] Figure 8 The relationship between the time Tc required for another ship that becomes an obstacle to the own ship 200 to reach the closest point 302 and the collision risk value is shown. When the time Tc is small, the collision risk value becomes high. In the example shown here, when the time Tc is less than the specified time, the collision risk value becomes high, and in this state, it is determined to be the maximum value 1.

[0153] Fig. 9 The present invention shows another embodiment of the route planning system, which determines the collision risk value when the ship 200 approaches the obstacle 204. The obstacle collision avoidance area 602 of the obstacle 204 is determined based on the position, moving direction, and speed of the obstacle 204, i.e., the ship. The obstacle collision avoidance area 602 of the obstacle 204 is located on the predicted future path 206 of the obstacle 204 based on the moving direction of the obstacle 204.

[0154] The obstacle collision avoidance area 602 of the obstacle 204 includes the obstacle 204 and the surrounding area of ​​the obstacle 204. To prevent collision, the obstacle collision avoidance area 602 of the obstacle 204 can be determined based on the safe passing distances 604a, 604b, and 604c, which are the minimum distances allowed on the side, front, and back of the ship 200, respectively.

[0155] In addition, the obstacle collision avoidance zone 602 is equivalent to the approach prohibition zone, and can simultaneously identify the direction in which there is a concern of collision and the distance between the ship 200 and the obstacle 204. Based on the moving body information and the obstacle information, the closest point 606 in the vertical direction or the closest point 608 in the horizontal direction between the ship 200 and the obstacle 204 (relative to the obstacle 204) is determined. When the closest point 606 or 608 in the vertical direction or the horizontal direction between the ship 200 and the obstacle 204 is located outside the obstacle collision avoidance zone 602, there is no concern of collision. Fig. 9 As shown, in this embodiment, the closest point 606 in the vertical direction at a distance Rx from the obstacle 204 and the closest point 608 in the horizontal direction at a distance Ry do not exist in the obstacle collision avoidance area 602, so there is no concern about collision.

[0156] In this embodiment, the collision risk value calculation unit 14 calculates the time required for the ship 200 to enter the obstacle collision avoidance area 602 based on the relative speed between the ship 200 and the obstacle 204. The collision risk value calculation unit 14 also calculates the collision risk value of the obstacle 204 based on the time until the ship 200 enters the obstacle collision avoidance area 602.

[0157] Fig.10 Another embodiment of the route planning system of the present invention is shown, which determines the collision risk value when the own ship 200 approaches the obstacle 204. The movable moving body collision avoidance area 702 of the own ship 200 is determined based on the position, moving direction, and speed of the own ship 200. The moving body collision avoidance area 702 of the own ship 200 is located on the planned route of the own ship 200 (i.e., the planned route 202 of the present embodiment) based on the moving direction of the own ship 200, and includes the own ship 200 and its surrounding area.

[0158] Based on the moving body information and the obstacle information, the closest point 304 in the vertical direction or the closest point 306 in the horizontal direction between the own ship 200 and the obstacle 204 relative to the own ship 200 is calculated. When the closest point 304 in the vertical direction and the closest point 306 in the horizontal direction between the own ship 200 and the obstacle 204 are located outside the moving body collision avoidance area 702, there is no danger of collision.

[0159] like Fig.10 As shown, in this embodiment, the closest point in the vertical direction 304 of the distance Rx from the own ship 200 is located in the movable moving body collision avoidance area 702, so there is a risk of collision. The own ship 200 continues to sail along the planned route in the current direction. If it enters the obstacle collision avoidance area 602 of the obstacle 204, there is a risk of collision.

[0160] In this embodiment, the collision risk calculation unit 14 determines the time required for the movable moving body collision avoidance zone 702 to enter the obstacle collision avoidance zone 602 based on the relative speed between the own ship 200 and the obstacle 204, the respective speeds of the own ship 200 and the obstacle 204, and the distance between the two. The collision risk value calculation unit 14 also calculates the collision risk value associated with the obstacle 204 based on the time required for the moving body collision avoidance zone 702 to enter the obstacle collision avoidance zone 602. The collision risk value associated with the obstacle 204 may also be calculated using the Figures 6 to 10 The collision risk value associated with the obstacle 204 is determined in the same manner as described in .

[0161] Fig.11 and Fig.12 Each of the foregoing diagrams is a block diagram of a route planning system 100 for safely navigating a vessel 200, which is another embodiment of the route planning system of the present invention. Fig.11 In the embodiment shown, the maximum collision risk value is included to calculate the congestion risk value, and in Fig.12 The embodiment shown does not differ except that the maximum collision risk value is excluded from the calculation of the congestion risk value. Figure 1 The embodiment of the route planning system of the present invention shown is different in that Fig.11 and Fig.12 The illustrated embodiment further includes an avoidance route setting unit 17 for generating an avoidance route.

[0162] exist Figure 1 and Figure 4 In one embodiment of the route planning system 100 shown, the main purpose is to evaluate the risk of collision with obstacles and decide whether to avoid them. Fig.11 and Fig.12 The embodiment of the route planning system 100 shown in FIG. 1 is different in that when it is determined that an avoidance route is required, an avoidance route is generated, and the collision risk of the avoidance route is evaluated to make a final decision. Fig.12 One embodiment of the structure shown will be described.

[0163] Fig.13 FIG. 1 is a diagram showing an example of the structure of an avoidance route setting unit in the route planning system of the present invention. Fig.13 In the illustrated embodiment of the route planning system of the present invention, the avoidance route setting unit 17 includes an avoidance route candidate proposal generating unit 22 and an avoidance route selecting unit 21 .

[0164] As a result of the collision risk assessment, when it is determined that the host ship 200 has deviated from the planned route and should navigate on an avoidance route, the avoidance route candidate plan generating unit 22 automatically generates one or more avoidance route candidate plans.

[0165] Fig.14 1 is a diagram showing an example of generating an avoidance route candidate plan in the route planning system of the present invention. The avoidance route candidate plan generating unit 22 automatically generates one or more route plans starting from the avoidance starting point WP1 on the planned route 202 and connected to the return point WP4 on the planned route 202. The route plan can pre-store a plurality of nodes connecting two points and a straight line or curve connecting them, and overlap with the avoidance starting point WP1 and the return point WP4 as an avoidance route candidate plan, or a curve can be generated each time by a suitable function.

[0166] In addition, if the positions of the avoidance starting point WP1 and the return point WP4 are also on the planned route 202, they can also be set arbitrarily for each candidate avoidance path. Regarding the avoidance starting point WP1, for example, when the risk of collision increases, it can be appropriately decided to set the current position of the own ship as the avoidance starting point WP1. Regarding the position of the return point WP4, as described later, it can be determined according to the setting policy of the distance of the avoidance path.

[0167] return Fig.13 For each of the plurality of avoidance route candidate solutions generated by the avoidance route candidate solution generation unit 22, the collision risk value calculation unit 14 calculates a collision risk value. Fig.14 As shown, obstacles 204, 302, 304, 306, 308, 310, and 312 with collision risks are captured near the ship. First, the collision risk values ​​are calculated for the above-mentioned multiple obstacles when sailing on the planned route 202, and then the maximum collision risk obstacle with the largest collision risk value is selected, and the maximum collision risk value and the congestion risk value are calculated. Here, since the obstacle 204 is equivalent to the maximum collision risk obstacle and the collision risk is high, it is determined that the avoidance path should be set.

[0168] Next, in the avoidance route candidate plan generation unit 22, a plurality of avoidance route candidate plans 1102 (plans shown by dotted lines) are generated, and for each avoidance route candidate plan 1102, the collision risk value for the plurality of obstacles is calculated in the same manner as described above, and then the maximum collision risk obstacle with the maximum collision risk value is selected, and the maximum collision risk value and the congestion risk value are calculated together. The risk evaluation unit 16 performs risk evaluation on them and selects the best avoidance route 212.

[0169] Next, the collision risk assessment when the ship 200 deviates from the planned route 202 and sails along the avoidance route 212 will be described.

[0170] Fig.15 The diagram shows an area surrounding the ship 200 when the ship 200 is navigating along the avoidance path 212 according to one embodiment of the present invention.

[0171] The route planning system 100 includes a route planning system 1, a route planning unit 2, a GNSS 3, one or more sensor units 4, a navigation control unit 5, and a display unit 6. The route planning system 1 includes a planned route acquisition unit 11, a mobile body information acquisition unit 12, an obstacle information acquisition unit 13, a collision risk value calculation unit 14, a congestion risk value calculation unit 15, a risk assessment unit 16, and an avoidance path setting unit 17. The route planning unit 2, the GNSS 3, one or more sensor units 4, the planned route acquisition unit 11, the mobile body information acquisition unit 12, the obstacle information acquisition unit 13, the collision risk value calculation unit 14, the risk assessment unit 16 and the reference Figure 1 The functions are performed in the same manner as described.

[0172] Here again, refer to Fig.11 The navigation avoidance path setting unit 17 is operably connected to the risk assessment unit 16 and is capable of communicating. The navigation avoidance path setting unit 17 generates the navigation avoidance path 212 of the host ship 200. The navigation avoidance path setting unit 17 uses the current position 214 or the predicted position as the reference point of the host ship 200, such as Figure 1 As shown, the alternative risk assessment unit 16 generates an avoidance route 212 .

[0173] exist Fig.15 In the example, the predicted position of the ship 200 is any one of the predicted position on the current route, the predicted position on the planned route 202, and the predicted position on the avoidance path 212. The avoidance path setting unit 17 can determine the predicted position based on the current speed and the rotation angular velocity of the ship 200. In the present embodiment, the avoidance path setting unit 17 generates the avoidance path 212 based on the maximum collision risk value calculated for the plurality of obstacles 204 and 206 and the congestion risk value associated with the planned route 202, i.e., the planned route.

[0174] When the maximum collision risk value and the congestion risk value calculated for the multiple obstacles related to the planned route 202 are high, the avoidance path setting unit 17 generates an avoidance path 212 of the ship 200 for avoiding collisions with the multiple obstacles 204 and 206. The generated avoidance path 212 can start the avoidance path from the avoidance start point (or way point) WP1 and return to the planned route 202 at the return point (or way point) WP4 to the planned route 202. In order to avoid collisions with the multiple obstacles 902 and 904, the ship driver, that is, the user who drives the ship 200, can navigate the ship 200 along the generated avoidance path 212.

[0175] As another embodiment, the ship 200 follows the avoidance path 212, and the avoidance path setting unit 17 determines whether to regenerate the avoidance path 212 based on a plurality of obstacles such as obstacles 902 and 904 along the avoidance path 212. In this embodiment, the planned route is the avoidance path 212.

[0176] When the avoidance route is newly generated, the collision risk value calculation unit 14 determines the current collision risk value associated with the planned route based on a plurality of collision risk values ​​for a plurality of obstacles that are intended to cross or approach the planned route.

[0177] When the current collision risk value associated with the planned route is high, the risk of the ship 200 colliding with multiple obstacles becomes high. The current collision risk value is sometimes represented by a numerical value from 0 to 1. In addition, the collision risk value is not limited to the above-mentioned numerical value, and the degree of danger can be set within an arbitrary range. In addition, the current collision risk value represents the degree of proximity when the ship 200 is navigating the planned route while maintaining the same speed, focusing on the most dangerous target among the surrounding targets.

[0178] Furthermore, the collision risk value calculation unit 14 calculates the avoidance collision risk value associated with the generated avoidance route based on a plurality of collision risk values ​​for a plurality of obstacles along the avoidance route.

[0179] When the collision avoidance risk value calculated in the avoidance path is high, the risk of collision between the ship 200 and multiple obstacles becomes high. The collision avoidance risk value indicates the degree of danger caused by approaching when the ship 200 focuses on the obstacle with the highest possibility of collision among the surrounding obstacles while maintaining the same speed while navigating the avoidance path. The collision avoidance risk value is sometimes represented by a numerical value between 0 and 1, but it is not limited to the evaluation based on the above numerical value, and the degree of collision possibility can be set within an arbitrary range.

[0180] The congestion risk value calculation unit 15 is configured to further calculate and determine the congestion risk value related to the planned route and the congestion risk value related to the avoidance path. Here, the congestion risk value indicates the degree to which multiple surrounding obstacles other than the obstacle with the greatest possibility of collision approach at the same time when the ship 200 maintains the same speed while sailing on the planned route.

[0181] The congestion risk value is calculated based on the collision risk value for each of the plurality of obstacles, and is calculated here by the value of the logical sum of them. The congestion risk values ​​associated with the planned route and the avoidance path can be represented by numerical values ​​ranging from 0 to 1, respectively, and are represented here by numerical values ​​ranging from 0 to 1. In addition, the method and range of setting the numerical value are not limited thereto, and can be set arbitrarily.

[0182] The congestion risk value for the planned route becomes higher when the number of obstacles approaching the ship 200 at the same time is large. When there is only one obstacle approaching the ship 200, in the example shown here, if the congestion risk value is calculated by excluding the maximum collision risk obstacle that is the object of the maximum collision risk, the congestion risk value is 0. When multiple obstacles (such as other ships) approach the ship 200, the collision risk value and the congestion risk value have different values.

[0183] For example, the collision risk value and the congestion risk value when a plurality of obstacles exist are determined based on the following equations (2) and (3).

[0184] Max(a,b)=(the greater of a and b) (2)

[0185] 1-Π(a,b)(1-(a,b))=1-(1-a)(1-b) (3)

[0186] In this embodiment, the collision risk value Risk can be calculated for each of the multiple obstacles. i , multiple obstacles are labeled with 'N' numbers. In this example, the collision risk values ​​of multiple obstacles are calculated by applying the following equations (2) to (4).

[0187] Risk coll =max i＝1,N (Risk i ) (4)

[0188] Here, N represents the number of the obstacle.

[0189] In this embodiment, by applying the following equations (3) to (5), the collision risk values ​​Risk calculated for each obstacle except for the obstacle with the largest collision risk value are calculated based on i Calculate the congestion risk value.

[0190] Risk cong =1-Π i＝1，N-1 (1-Risk i ) (5)

[0191] Reference Fig.11 The navigation control unit 5 can be operably connected to and communicate with the navigation avoidance path setting unit 17. The navigation control unit 5 is configured to monitor and control the navigation of the own ship 200, and control the own ship 200 to deviate from the planned route 202 to navigate when it is determined that collision avoidance is necessary based on the moving body information and obstacle information. As a result, the ship driver can avoid collision with multiple obstacles when the collision risk value is high, and can safely navigate the own ship 200 along the planned route or the navigation avoidance path.

[0192] In this embodiment, although the display unit 6 is outside the route planning system 1, those skilled in the art should understand that the route planning system of the present invention is not limited thereto. In another embodiment, the display unit 6 is inside the route planning system 1 without departing from the scope of the present invention.

[0193] Refer to appropriately Fig.16 and Fig.17 The flowchart shown illustrates the route planning method 1200 according to an embodiment of the present invention.

[0194] In step 1202, the planned route acquisition unit 11 receives the planned route 202 which is the route of the ship 200. The route planning unit 2 can provide one or more routes for the navigation of the ship 200 from the departure point (departure point) to the destination.

[0195] In step 1204, the obstacle information acquisition unit 13 receives obstacle information from one or more sensor units 4. The obstacle information includes the position, moving direction, and speed of the plurality of obstacles 204, 206 (or 902, 904). The obstacle information may also include one or more information related to other moving bodies such as other ships, tidal currents, weather, reefs, stranded ships, etc.

[0196] In step 1206 , the moving object information acquiring unit 12 receives moving object information such as the position, moving direction, and speed of the ship 200 .

[0197] In step 1208, the collision risk value calculation unit 14 obtains a plurality of collision risk values ​​associated with the planned route of the ship 200 based on the moving body information and the obstacle information. In one embodiment, the route to be navigated is the planned route 202, but in another embodiment, the route to be navigated is the avoidance route 212.

[0198] In step 1210 , the risk assessment unit 16 determines that the collision risk of sailing along the planned route is low, and if it is determined that the ship 200 does not need to deviate from the planned route for avoidance and does not need to generate an avoidance route, step 1204 is executed.

[0199] In step 1210 , when the risk assessment unit 16 determines that the collision risk on the planned route is high and needs to request the ship 200 to generate an avoidance route in order to avoid the planned route, step 1212 is executed.

[0200] In step 1212, the avoidance path setting unit 17 generates an avoidance path for the host ship 200 and displays the avoidance path on the image of the display unit 6. In step 1214, the collision risk value calculation unit 14 determines a plurality of collision risk values ​​associated with a plurality of obstacles along the planned route. The collision risk value calculation unit 14 calculates collision risk values ​​for the planned route and the avoidance path, respectively.

[0201] In step 1216 , the congestion risk value calculation unit 15 calculates and obtains the congestion risk value of the planned route, the congestion risk value of the avoidance route, and the distance to the merging point (return point to the planned route) of the own ship.

[0202] In step 1218, the risk assessment unit 16 excludes the avoidance routes that exceed the congestion risk value of the planned route from the candidates. In step 1220, the avoidance routes that exceed the predetermined congestion risk value are excluded from the candidates.

[0203] In step 1222, the shortest path to the merging point is selected as the avoidance path of the moving object (own ship). Then, in step 1224, the moving object (own ship) navigates along the avoidance path.

[0204] As described above, the route planning system 1 of the present invention enables the ship 200 to navigate safely by avoiding collisions or intersections with multiple surrounding obstacles such as other ships and terrain that serve as obstacles in the planned route (planned route 202 or avoidance path 212) displayed in the image on the display unit 6 and the generated avoidance path (avoidance path 212 or other avoidance paths) through the ship driver, i.e., the operator driving the ship.

[0205] The above is a description of the embodiments of the route planning system and the route planning method of the present invention. However, the various exemplified logic blocks and components described in association with the embodiments of the invention shown here can be implemented or executed by a machine such as a processor.

[0206] The processor may be a microprocessor, but may also be a controller, a microcontroller, a state machine, or a combination thereof. The processor may include circuits configured to process computer executable instructions. In another embodiment, the processor includes an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable devices that do not process computer executable instructions but perform logic operations.

[0207] The processor may be, for example, a combination of a digital signal processor (DSP) and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or other such structures, and the combination may be implemented as a computing device.

[0208] The description herein is mainly based on digital technology, but the processor may also include mainly analog components. For example, part or all of the signal processing algorithms described herein can be implemented by analog circuits or mixed analog and digital circuits.

[0209] The computing environment includes a microprocessor, a mainframe computer, a digital signal processor, a portable computing device, a device controller, or a computer system based on a computing engine within a device, but is not limited thereto and can include any type of computer system.

Claims

1. A route planning system, wherein: have: a planned route acquisition unit that acquires planned route information indicating a planned route of a mobile body moving on water; A moving body information acquisition unit, which acquires moving body information including the position and moving direction of the moving body; an obstacle information acquisition unit for acquiring obstacle information including a position and a moving direction for each of a plurality of obstacles existing around the moving body; a collision risk value calculation unit that calculates a collision risk value indicating a risk level of collision between the moving object and each obstacle based on the moving object information and the obstacle information; a congestion risk value calculation unit that calculates, for a congestion risk obstacle including a plurality of the obstacles, a congestion risk value indicating a degree of simultaneous approach of the obstacles included in the congestion risk obstacle based on a collision risk value corresponding to each of the obstacles included in the congestion risk obstacle; as well as The risk assessment unit determines whether the mobile body needs to navigate an avoidance route having a route different from the planned route based on the congestion risk value.

2. The route planning system according to claim 1, wherein: The risk assessment unit includes: a congestion risk assessment unit that compares a congestion risk threshold value set for the congestion risk value with the congestion risk value and outputs a congestion risk assessment result; The risk assessment unit determines whether it is necessary to navigate on an avoidance route based on the congestion risk assessment result.

3. The route planning system according to claim 2, wherein: The method further comprises: a maximum collision risk obstacle selecting unit for selecting a maximum collision risk obstacle corresponding to a maximum collision risk value from among the obstacles; The risk assessment unit further comprises: a maximum collision risk assessment unit, which compares a collision risk threshold value set for the maximum collision risk value with the maximum collision risk value and outputs a maximum collision risk assessment result; The risk assessment unit determines whether it is necessary to navigate on an avoidance path based on the congestion risk assessment result and the maximum collision risk assessment result.

4. The route planning system according to claim 3, wherein: The method further comprises: an avoidance route setting unit which sets an avoidance route different from the planned route for a part or all of the untraveled route of the mobile body in the planned route when the risk assessment unit determines that the avoidance route needs to be set.

5. The route planning system according to claim 4, wherein: The avoidance path setting unit further comprises: an avoidance route candidate plan generating unit for generating one or more avoidance route candidate plans of routes different from the planned route as candidates for the avoidance route between the avoidance start point on the unnavigated route and the planned route return point; as well as The avoidance path selection unit selects an avoidance path from among the avoidance path candidate proposals.

6. The route planning system according to claim 5, wherein: The congestion risk value calculation unit calculates the congestion risk value of the planned route based on a value of a logical sum of a plurality of collision risk values ​​including a maximum collision risk value among the plurality of collision risk values.

7. The route planning system according to claim 5, wherein: The congestion risk value calculation unit calculates the congestion risk value of the planned route based on a value of a logical sum of a plurality of collision risk values ​​excluding a maximum collision risk value among the plurality of collision risk values.

8. The route planning system according to claim 7, wherein: The congestion risk value calculation unit calculates the congestion risk value based on collision risk values ​​corresponding to a plurality of obstacles selected from among a plurality of obstacles corresponding to the obstacle information acquired by the obstacle information acquisition unit.

9. The route planning system according to claim 8, wherein: The congestion risk value calculation unit calculates the congestion risk value based on the collision risk value corresponding to each obstacle in the quasi-maximum collision risk obstacle group, wherein the quasi-maximum collision risk obstacle group includes a quasi-maximum collision risk obstacle corresponding to a quasi-maximum collision risk value that is the second largest collision risk value after the maximum collision risk value, and an obstacle having a collision risk value smaller than the quasi-maximum collision risk value.

10. The route planning system according to claim 9, wherein: The congestion risk value calculation unit calculates the congestion risk value of the planned route and the congestion risk value of the avoidance route based on a value of a logical sum of the plurality of collision risk values.

11. The route planning system according to any one of claims 5 to 10, wherein: The collision risk value calculation unit further calculates the maximum collision risk value for each of the one or more avoidance path candidate solutions. The congestion risk calculation unit further calculates the congestion risk value for each of the one or more avoidance route candidate solutions.

12. The route planning system according to claim 11, wherein: The collision risk value calculation unit calculates, for each of the avoidance route candidate plans, the maximum collision risk value when the mobile body navigates according to the avoidance route candidate plan. The avoidance route selection unit selects an avoidance route candidate having the maximum collision risk value equal to or less than a predetermined threshold as the avoidance route, The avoidance path selection unit comprises: The avoidance route navigation determination unit determines whether the maximum collision risk value corresponding to the selected avoidance route is smaller than the maximum collision risk value for the planned route, and if so, determines that it is necessary to navigate the avoidance route.

13. The route planning system according to claim 12, wherein: The congestion risk value calculation unit calculates a congestion risk value of the navigation avoidance route when the mobile body navigates along the selected navigation avoidance route. The avoidance route selection unit further determines that it is necessary to navigate along the selected avoidance route when the congestion risk value of the avoidance route is smaller than the congestion risk value for the planned route.

14. The route planning system according to claim 13, wherein: The avoidance route selection unit further considers the distance traveled by the mobile body in each of the avoidance route candidate plans for each of the avoidance route candidate plans, and determines whether avoidance is necessary.

15. The route planning system according to claim 14, wherein: The avoidance route selection unit selects, as the avoidance route, a candidate navigation route having a minimum navigation distance for the mobile body among the candidate navigation routes for which both the maximum collision risk value and the congestion risk value are equal to or less than a predetermined threshold.

16. The route planning system according to any one of claims 1 to 10, wherein: The moving object information includes the moving speed of the moving object.

17. The route planning system according to claim 16, wherein: The obstacle information includes the moving speed of the obstacle.

18. The route planning system according to claim 13, wherein: The obstacle information includes at least one of the following information: Information detected by at least one of a radar, a laser radar, a sonar, and an image sensor installed on the mobile object; Information received by an automatic identification system receiver; Information sent by ships other than the mobile object; Information detected by wireless communication at a location other than the mobile object.

19. The route planning system according to claim 18, wherein: The obstacle information also includes information related to other objects including at least one of other ships, currents, weather, reefs, and stranded ships.

20. The route planning system according to claim 19, wherein: The system further comprises: a display for displaying the avoidance path together with the planned route on a display image.

21. The route planning system of claim 20, wherein: Also features: a route planning unit that provides one or more routes for navigation of the mobile body from the departure point to the destination; and One or more sensor units for acquiring the obstacle information.

22. A route planning method, wherein: acquiring planned route information indicating a planned route of a mobile body moving on water, Acquiring moving object information including the position, moving direction and moving speed of the moving object, Obstacle information including position, moving direction and moving speed is obtained for each of a plurality of obstacles existing around the moving object. Based on the moving object information and the obstacle information, a collision risk value indicating the degree of risk of the moving object colliding with each obstacle is calculated; selecting a maximum collision risk obstacle corresponding to a maximum collision risk value among the obstacles, For one or more of the congestion risk obstacles including the maximum collision risk obstacle, based on the collision risk value corresponding to each of the obstacles included in the congestion risk obstacles, a congestion risk value indicating the degree to which the obstacles included in the congestion risk obstacles are approached at the same time is calculated; Based on the congestion risk value, it is determined whether the mobile object needs to navigate on an avoidance route having a path different from the planned route.

23. The route planning method according to claim 22, wherein: Whether it is necessary to navigate the avoidance route is determined by comparing a congestion risk threshold set for the congestion risk value with the congestion risk value.

24. The route planning method according to claim 23, wherein: Whether it is necessary to navigate along the avoidance path is also determined by comparing a collision risk threshold set for the maximum collision risk value with the maximum collision risk value.

25. The route planning method according to claim 24, wherein: When it is determined that the avoidance route needs to be set, an avoidance route different from the planned route is set for a part or all of the untraveled route of the mobile body in the planned route.

26. The route planning method according to claim 25, wherein: Between the avoidance start point on the unnavigated route and the planned route return point, one or more avoidance route candidate solutions are generated as candidates for the avoidance route, which are different from the planned route. An avoidance path is selected from among the avoidance path candidate solutions.

27. The route planning method according to claim 26, wherein: The congestion risk value of the planned route is calculated based on a value of a logical sum of a plurality of collision risk values ​​excluding a maximum collision risk value among the plurality of collision risk values.

28. The route planning method according to any one of claims 25 to 27, wherein: further calculating the maximum collision risk value for each of the one or more candidate avoidance paths, The congestion risk value is also calculated for each of the one or more avoidance path candidate solutions.

29. The route planning method according to claim 28, wherein: For each of the candidate avoidance paths, the maximum collision risk value when the mobile object navigates according to the candidate avoidance paths is calculated; The candidate avoidance path for which the maximum collision risk value is below a predetermined threshold is selected as the avoidance path, It is determined whether the maximum collision risk value corresponding to the selected avoidance path is smaller than the maximum collision risk value for the planned route, and if so, it is determined that it is necessary to navigate on the avoidance path.

30. The route planning method according to claim 29, wherein: Among the avoidance route candidates for which both the maximum collision risk value and the congestion risk value are less than or equal to a predetermined threshold value, the avoidance route candidate having the shortest navigation distance of the mobile body is selected as the avoidance route.

31. A computer program, which is a computer executable program, wherein: The computer performs the following steps: acquiring planned route information indicating a planned route of a mobile body moving on water, Acquiring moving object information including the position, moving direction and moving speed of the moving object, Obstacle information including position, moving direction and moving speed is obtained for each of a plurality of obstacles existing around the moving object. Based on the moving object information and the obstacle information, a collision risk value indicating the degree of risk of the moving object colliding with each obstacle is calculated; selecting a maximum collision risk obstacle corresponding to a maximum collision risk value among the obstacles, For one or more of the congestion risk obstacles including the maximum collision risk obstacle, based on the collision risk value corresponding to each of the obstacles included in the congestion risk obstacles, a congestion risk value indicating the degree to which the obstacles included in the congestion risk obstacles are approached at the same time is calculated; Based on the congestion risk value, it is determined whether the mobile object needs to navigate on an avoidance route having a path different from the planned route.

32. The route planning system of claim 10, wherein: The congestion risk value calculation unit calculates the congestion risk value of the planned route and the congestion risk value of the avoidance route by the following formula: Risk Cong =1-Π i＝1，N-1 (1-Risk i ) Among them, Risk i Represents the collision risk value of each obstacle, and i is an integer greater than 1.

33. The route planning system of claim 17, wherein: The collision risk value calculation unit further calculates, based on the mobile body information and the obstacle information, a first closest distance between the mobile body and the obstacle, and a second closest distance in the navigation direction of the mobile body and a third closest distance in a direction perpendicular to the navigation direction, both or one of the closest distances. The collision risk value calculation unit obtains a collision risk value of the obstacle based on the first closest distance and at least one of a second closest distance and a third closest distance.

34. The route planning system of claim 33, wherein: When the first closest distance is equal to or smaller than a predetermined distance and the risk assessment unit determines that the collision risk is high, the mobile object needs to avoid the obstacle by avoiding the planned route and navigating on the avoidance path.

35. The route planning system of claim 33, wherein: When the second closest distance or the third closest distance is equal to or smaller than a predetermined distance and the risk assessment unit determines that the collision risk is high, the mobile object needs to avoid the obstacle by avoiding the planned route and navigating on the avoidance path.

36. The route planning system of claim 33, wherein: The collision risk value calculation unit calculates a collision risk value of the mobile object colliding with the obstacle based on the first closest distance and a time required for the obstacle to reach the first closest distance.

37. The route planning system of claim 33, wherein: Determine the obstacle avoidance zone of the obstacle based on the position, moving direction and speed of the obstacle, The collision risk value calculation unit calculates the time required for the moving body to enter the obstacle collision avoidance area based on the relative speed between the moving body and the obstacle, and calculates the collision risk value of the obstacle based on the time until the moving body enters the obstacle collision avoidance area.

38. The route planning system of claim 33, wherein: The obstacle avoidance zone of the obstacle is determined based on the position, moving direction and speed of the obstacle, and the movable mobile body avoidance zone of the mobile body is determined based on the position, moving direction and speed of the mobile body. The collision risk calculation unit determines the time required for the movable mobile body avoidance zone to enter the obstacle avoidance zone based on the relative speed of the mobile body and the obstacle, based on the respective speeds of the mobile body and the obstacle and the distance between the two, and calculates the collision risk value of the obstacle based on the time required for the movable mobile body avoidance zone to enter the obstacle avoidance zone.

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