Route planning system and route planning method

Abstract

Provided are a route planning device and method for sailing safely 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 moving body position and a moving direction; an obstacle information acquisition unit that acquires obstacle information including a position and a movement direction for obstacles in the vicinity of the moving body; a voyage avoidance path acquisition unit for acquiring voyage avoidance path information different from the planned route by using the voyage avoidance starting point as a starting point; a collision risk value calculation unit that calculates a collision risk value between the moving body and each obstacle on the basis of the moving body information and the obstacle information; the maximum collision risk value comparison part is used for calculating and comparing maximum collision risk values for the planned route and the voyage avoiding path respectively; and a route change signal output unit which, when the maximum collision risk value of the voyage avoidance path is lower than the planned route, instructs a route change signal to change the voyage avoidance path.

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 collisions with surrounding obstacles and other ships to make the ship and other mobile bodies navigate safely along the planned route. In addition, sometimes it is necessary to assist navigation in the state of the ocean and tides. In order to meet the above needs, a system, device and method are provided to assist the ship driver to safely navigate the mobile body by setting an avoidance path to avoid collisions with multiple obstacles and other ships.

[0007] However, in order for the ship's pilot to safely navigate the mobile body, the avoidance path set and switched is compared with the original planned path to verify whether the risk of collision is reduced. In addition, when taking an avoidance action based on the verification result, it is expected that the route length of the original planned route and the avoidance path will be compared to be able to more flexibly choose whether to take an avoidance action.

[0008] In order to solve the above-mentioned problems, the route planning system of the present invention comprises: a planned route acquisition unit, which acquires planned route information representing 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; 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; and an avoidance path acquisition unit, which acquires avoidance path information representing an avoidance path different from the planned route, taking an avoidance starting point at which the mobile body starts to avoid as a starting point. The invention also 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 maximum collision risk value comparison unit, which compares the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path, wherein the maximum collision risk value of the planned route is the maximum collision risk value among the collision risk values ​​when the mobile body navigates on the planned route with the avoidance starting point as the starting point, and the maximum collision risk value of the avoidance path is the maximum collision risk value among the collision risk values ​​when the mobile body navigates on the avoidance path with the avoidance starting point as the starting point; and a route change signal output unit, which outputs a route change signal indicating a route change to the avoidance path when the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route.

[0009] The avoidance start point may be the current navigation position of the mobile body on the planned route or moving along the planned route, or may be any position on an unnavigated route on the planned route, or may be the future position of the mobile body calculated based on the current navigation position of the mobile body moving along the planned route.

[0010] In addition, the route planning system of the present invention also has: a distance calculation unit, which calculates the distance of the mobile body when it sails on the planned route for a specified time from the avoidance starting point, and the distance of the mobile body when it sails on the avoidance path for a specified time from the avoidance starting point. The route change signal output unit can also decide whether to output the route change signal based on the distance on the planned route and the distance on the avoidance path.

[0011] The route change signal output unit can also calculate the difference between the distance on the planned route and the distance on the avoidance path, and output the route change signal when the difference is below a specified value. It can also calculate the ratio of the distance on the avoidance path to the distance on the planned route, and output the route change signal when the ratio is below a specified value.

[0012] Furthermore, the route change signal output unit can also output a route change signal when the maximum collision risk value is below a pre-set reference range. When the maximum collision risk value is not less than the reference range, it decides whether to output a route change signal based on the distance on the planned route and the distance on the avoidance path.

[0013] Furthermore, the moving object information may also include information related to the speed of the moving object, and the obstacle information may also include information related to the speed of the obstacle. In addition, these may be appropriately calculated based on changes in the position and moving direction of the moving object.

[0014] The route planning system of the present invention also includes: a congestion risk value calculation unit, which calculates a congestion risk value indicating the degree of simultaneous approach of obstacles included in a congestion risk obstacle based on a collision risk value corresponding to each of the obstacles included in the congestion risk obstacle for a congestion risk obstacle including multiple obstacles; and a congestion risk value comparison unit, which compares the congestion risk value of a planned route when the mobile body navigates on the planned route with the avoidance starting point as the starting point, i.e., the congestion risk value of the planned route, with the congestion risk value of a planned route when the mobile body navigates on the avoidance path with the avoidance starting point as the starting point, i.e., the congestion risk value of the avoidance path. When the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route and the congestion risk value of the avoidance path is lower than the congestion risk value of the planned route, the route change signal output unit may also indicate a route change to the avoidance path.

[0015] In addition, the route planning system of the present invention in the above structure also has: a distance calculation unit, which calculates the distance when the mobile body navigates on the planned route for a specified time from the avoidance starting point, and the distance when the mobile body navigates on the avoidance path for a specified time from the avoidance starting point. The route change signal output unit also determines whether it is necessary to output a route change signal based on the distance on the planned route and the distance on the avoidance path.

[0016] Here, the distance setting unit sets the return point on the planned route for the mobile body navigating on the avoidance path, and calculates the distance between the avoidance starting point and the return point on the planned route, and the distance between the avoidance starting point and the return point on the avoidance path. The route change signal output unit can also decide whether to output the route change signal based on the distance on the planned route and the distance on the avoidance path.

[0017] The route change signal output unit can also calculate the difference between the distance on the planned route and the distance on the avoidance path, and output the route change signal when the difference is below a specified value, or calculate the ratio of the distance on the avoidance path to the distance on the planned route, and output the route change signal when the ratio is below a specified value.

[0018] The route change signal output unit can also output a route change signal when the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is within a pre-set reference range. When the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is outside the reference range, it is determined whether the route change signal needs to be output based on the distance on the planned route and the distance on the avoidance path.

[0019] 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 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 ​​excluding the maximum collision risk value among the multiple collision risk values.

[0020] The congestion risk value calculation unit may also calculate the congestion risk value based on the collision risk values ​​corresponding to the selected multiple obstacles among the multiple obstacles corresponding to the obstacle information acquired by the obstacle information acquisition unit. 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 the quasi-maximum collision risk value of 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. The congestion risk value calculation unit may also calculate 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 multiple collision risk values.

[0021] In the route planning system of the present invention, the collision risk value calculation unit calculates the maximum collision risk value of the mobile body when navigating along each of the avoidance path candidate plans, and the avoidance path selection unit can also select the avoidance path candidate plan as the avoidance path based on the maximum collision risk value.

[0022] Furthermore, in the above configuration, the congestion risk calculation unit may calculate a congestion risk value for each of the one or more avoidance route candidate solutions, and the avoidance route acquisition unit may set the avoidance route based on the maximum collision risk value and the congestion risk value.

[0023] In the above, the obstacle information includes at least one of the following information: information detected by at least one device including radar, LIDAR, SONAR, and image sensor 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.

[0024] The obstacle information also includes information related to other objects including at least one of other ships, currents, weather, reefs, or stranded ships.

[0025] The route planning system of the present invention may also include: a display that displays the avoidance path together with the planned route on a display image. It may also include: a route planning unit that provides one or more routes for the navigation of a mobile body from a departure point to a destination; and one or more sensor units that obtain obstacle information.

[0026] In the route planning system of the present invention, the avoidance path acquisition unit may also acquire the avoidance path information generated outside the mobile body via wireless communication, or may acquire information related to the avoidance path set in the avoidance path setting unit. The avoidance path setting unit includes: an avoidance path candidate plan generation unit that generates one or more avoidance path candidate plans that are candidates for avoidance paths that are different from the planned route between the avoidance start point and the return point on the planned route; and an avoidance path selection unit that selects an avoidance path from the avoidance path candidate plans.

[0027] Furthermore, the avoidance route setting unit may include: a display that displays a nautical chart on which the mobile body is navigating; and a user interface that receives a route set by a user from the nautical chart displayed on the display and acquires information on the avoidance route set therein.

[0028] The route planning method of the present invention plans a route from a departure point to a destination, wherein planned route information representing a planned route of a mobile body moving on water is obtained; mobile body information including the position and moving direction of the mobile body is obtained; obstacle information including the position and moving direction is obtained for each of a plurality of obstacles existing around the mobile body; and an avoidance path different from the planned route is obtained with an avoidance starting point at which the mobile body starts to avoid navigation as a starting point. Then, for the collision risk value representing the risk degree of collision between the mobile body and each obstacle, based on the mobile body information and the obstacle information, the maximum collision risk value among the collision risk values ​​when the mobile body navigates on the planned route with the avoidance starting point as the starting point, i.e., the maximum collision risk value of the planned route, and the maximum collision risk value among the collision risk values ​​when the mobile body navigates on the avoidance path with the avoidance starting point as the starting point, i.e., the maximum collision risk value of the avoidance path, are calculated respectively; the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path are compared, and when the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route, a route change signal indicating a route change to the avoidance path is output.

[0029] The avoidance start point may be the current navigation position of the mobile body on the planned route or moving along the planned route, or may be any position on an unnavigated route on the planned route, or may be the future position of the mobile body calculated based on the current navigation position of the mobile body moving along the planned route.

[0030] In addition, the route planning method of the present invention also includes a distance calculation unit, which calculates the distance when the mobile body navigates on the planned route for a specified time from the avoidance starting point, and the distance when the mobile body navigates on the avoidance path for a specified time from the avoidance starting point. The route change signal output unit can also decide whether to output the route change signal based on the distance on the planned route and the distance on the avoidance path.

[0031] The route planning method of the present invention can also output a route change signal when the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is within a pre-set reference range. When the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is outside the reference range, it is determined whether a route change signal needs to be output based on the distance on the planned route and the distance on the avoidance path.

[0032] The route planning method of the present invention can also calculate a congestion risk value representing the degree of simultaneous approach of obstacles included in a 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 multiple obstacles; calculate the congestion risk value of a planned path with the avoidance starting point as the starting point on the planned route, and calculate the congestion risk value of an avoidance path with the avoidance starting point as the starting point on the avoidance path; compare the congestion risk value of the planned path and the congestion risk value of the avoidance path; and indicate a route change to the avoidance path when the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route and the congestion risk value of the avoidance path is lower than the congestion risk value of the planned route.

[0033] In addition, the route planning method of the present invention can also set a regression point for the mobile body to return on the planned route, calculate the distance on the planned route between the avoidance starting point and the regression point, and the distance on the avoidance path between the avoidance starting point and the regression point on the avoidance path, and decide whether to output a route change signal based on the distance on the planned route and the distance on the avoidance path.

[0034] The computer program of the present invention is a computer executable program, wherein the following steps are executed by a computer: obtaining planned route information representing a planned route of a mobile body moving on water; obtaining mobile body information including a position and a moving direction of the mobile body; obtaining obstacle information including a position and a moving direction for each of a plurality of obstacles existing around the mobile body; obtaining an avoidance path different from the planned route with an avoidance starting point as a starting point; for a collision risk value representing the risk level of collision between the mobile body and each obstacle, respectively calculating, based on the mobile body information and the obstacle information, the maximum collision risk value of the planned route, which is the maximum collision risk value among the collision risk values ​​when the mobile body navigates on the planned route with the avoidance starting point as the starting point, and the maximum collision risk value of the avoidance path, which is the maximum collision risk value among the collision risk values ​​when the mobile body navigates on the avoidance path with the avoidance starting point as the starting point; comparing the maximum collision risk value of the planned route with the maximum collision risk value of the avoidance path, and outputting a route change signal indicating a route change to the avoidance path when the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route.

[0035] When the route planning system of the present invention detects multiple obstacles on the planned route, it compares the collision risk between the avoidance path set ahead of the current position or predicted position of the mobile body and the original planned route. Since it is possible to choose whether to take avoidance action based on the result, it is possible to enable mobile bodies such as the ship to navigate safely. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] 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.

[0037] Figure 1 This is a block diagram showing the structure of one embodiment of the route planning system of the present invention.

[0038] Figure 2 This is a diagram showing the positional relationship between a ship sailing on a planned route and other ships approaching the ship in one embodiment of the route planning system of the present invention.

[0039] Figure 3 This is a diagram showing the positional relationship between a mobile object (own ship) and an obstacle (another ship) for calculating a collision risk value in one embodiment of the route planning system of the present invention.

[0040] Figure 4This is a diagram showing collision risk values ​​corresponding to positional relationships between the own ship and other ships in one embodiment of the route planning system of the present invention.

[0041] Figure 5 This is a diagram showing the relationship between the time until the own ship and another ship reach the closest distance and the collision risk value in one embodiment of the route planning system of the present invention.

[0042] Figure 6 The diagram is a diagram showing the positional relationship between the own ship and other ships for calculating the collision risk value in one embodiment of the route planning system of the present invention, and is a diagram showing the collision avoidance area set around the other ships.

[0043] Figure 7 It means in Figure 6 The diagram shown further shows a diagram in which a collision avoidance area (area) is set around the ship.

[0044] Figure 8 This is a diagram showing an example of the relationship between the own ship and other ships in the route planning system of the present invention.

[0045] Fig. 9 The present invention is a diagram showing changes in the distance between the own ship and other ships when the own ship is navigating on a planned route and changes in the distance between the own ship and other ships when the own ship is navigating on an avoidance path in one embodiment of the route planning system of the present invention.

[0046] Fig.10 This is a diagram showing the relationship between the maximum collision risk value when the ship navigates on the planned route and the maximum collision risk value when the ship navigates on the avoidance path in one embodiment of the route planning system of the present invention.

[0047] Fig.11 is a diagram showing the structure of another embodiment of the route planning system of the present invention, Figure 1 The structure shown is a block diagram of the structure of a distance calculation unit.

[0048] Fig.12 It is a graph showing the relationship between the maximum collision risk value when the ship is navigating the planned route and the maximum collision risk value when navigating the avoidance path in another embodiment of the route planning system of the present invention, and is a graph showing a preset reference range.

[0049] Fig.13 It is a graph showing the relationship between the maximum collision risk value when the ship is navigating the planned route and the maximum collision risk value when navigating the avoidance path in another embodiment of the route planning system of the present invention, and is a graph showing a value outside a preset reference range.

[0050] Fig.14 This is a diagram showing an example of the relationship between the distance from the avoidance start point to the return point when the ship is navigating on the planned route and the distance from the avoidance start point to the return point when navigating on the avoidance path in another embodiment of the route planning system of the present invention.

[0051] Fig.15 This is another diagram showing another example of the relationship between the distance from the avoidance start point to the return point when the ship is navigating on the planned route and the distance from the avoidance start point to the return point when navigating on the avoidance path in another embodiment of the route planning system of the present invention.

[0052] Fig.16 is a diagram showing the structure of another embodiment of the route planning system of the present invention, Figure 1 The structure shown is a block diagram of the structure further including a congestion risk value calculation unit and a congestion risk value comparison unit.

[0053] Fig.17 This is a diagram showing an example of a state in which a host ship and a plurality of other ships are present around the host ship in still another embodiment of the route planning system of the present invention.

[0054] Fig.18 is a diagram showing the structure of another embodiment of the route planning system of the present invention, Figure 1 The structure shown is a block diagram of the structure that further includes a congestion risk value calculation unit, a congestion risk value comparison unit, and a distance calculation unit.

[0055] Fig.19 This is a diagram showing the relationship between the congestion risk value when the ship navigates on the planned route and the congestion risk value when the ship navigates on the avoidance route in another embodiment of the route planning system of the present invention.

[0056] Fig. 20 In another embodiment of the route planning system of the present invention, a graph showing the relationship between the congestion risk value when the ship is navigating the planned route and the congestion risk value when navigating the avoidance route is outside a preset reference range.

[0057] Fig.21 This is a flowchart showing the processing in one embodiment of the route planning method of the present invention.

[0058] Fig. 22 Yes means Fig.21 The following is a continuation of the flowchart of the processing in one embodiment of the route planning method of the present invention.

[0059] Description of Reference Numerals

[0060] 1Route planning device

[0061] 2Route Planning Department

[0062] 3. GNSS receivers

[0063] 4 One or more sensor parts

[0064] 5Navigation Control Department

[0065] 6Display unit (display)

[0066] 7Avoidance route setting unit

[0067] 8 Avoidance route alternative plan generation unit

[0068] 9 Avoidance Path Selection Unit

[0069] 11Plan route acquisition department

[0070] 12Mobile body information acquisition unit

[0071] 13Obstacle Information Acquisition Unit

[0072] 14 Avoidance Path Acquisition Unit

[0073] 15Collision risk (danger level) calculation unit

[0074] 16 Maximum collision risk value comparison unit

[0075] 17 Route change signal output unit

[0076] 18Distance calculation unit

[0077] 19Congestion Risk Calculation Department

[0078] 20 Congestion Risk Comparison Department

[0079] 100 Route Planning System

[0080] 200 Mobile object (own ship)

[0081] 202 planned route

[0082] 204, 206, 902, 904 obstacles

[0083] 212 Avoidance Path

[0084] 302, 304, 306, 308, 310, 312 Congestion risk objects and obstacles

[0085] 1102 Avoidance Path Alternative Plan

[0086] WP1 Avoidance start point (from planned route to avoidance path)

[0087] WP4 Return point (from the avoidance path to the planned route) DETAILED DESCRIPTION

[0088] 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.

[0089] 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.

[0090] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof.

[0091] Figure 1 This is a block diagram showing the configuration of a route planning system 100 for safely navigating a mobile object 200 according to an embodiment of the present invention. Figure 2 This is a diagram showing the positional relationship between a ship sailing on a planned route and other ships approaching the ship in one embodiment of the route planning system of the present invention.

[0092] Hereinafter, the mobile object 200 is also referred to as the own ship 200 as appropriate.

[0093] 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.

[0094] The route planning system 100 is used for the purpose of enabling the ship 200 to navigate safely without colliding with a ship recognized as an obstacle, adverse sea conditions or weather, or surrounding obstacles as other obstacles. The ship driver, i.e., the operator driving the ship 200, receives assistance from the route planning system 100 or controls the ship based on the navigation control unit 5 while referring to a display 6 appropriately equipped on the ship or assembled in the route planning system 100, so that the ship 200 navigates along the planned route 202.

[0095] The navigation control unit 5 is operably connected to the route change signal output unit 17. The navigation control unit 5 is configured to monitor and control the navigation of the ship 200 based on the judgment of whether the ship 200 deviates from and avoids the planned route 202 or the avoidance path 212 set for avoiding obstacles, or continues to navigate along the planned route 202 or the avoidance path 212.

[0096] like Figure 2As shown, in this embodiment, the planned route 202 is the route that the ship 200 should follow in order to navigate and safely reach the destination. The planned route 202 shows the route of the ship 200 and the heading direction from the current position of the ship 200.

[0097] exist Figure 1 In the present invention, the route planning unit 2 is configured to store a plurality of routes for the navigation of the own 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 on the location of the departure point and the destination of the navigation of the own ship 200 by operating peripheral devices such as a keyboard and a mouse.

[0098] 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.

[0099] The route planning unit 2 receives user input from the ship driver or related personnel, and selects a path of the planned route 202 used for 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.

[0100] The route planning system 100 uses information related to mobile objects 200 such as other ships and a plurality of obstacles 204 and 206 located in the area around the ship 200 in order to safely navigate the ship 200 from the departure point to the destination along the planned route 202 .

[0101] The global navigation satellite system (GNSS) receiver 3 is generally installed on the ship 200 to obtain the 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. In addition, the moving body information may also include information related to the speed of the moving body, and the obstacle information may also include information related to the speed of the obstacle. In addition, these may also be appropriately calculated according to the changes in the position and moving direction of the moving body.

[0102] 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.

[0103] 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.

[0104] In this embodiment, for easy understanding, Figure 2 The obstacles shown as existing around the ship are only obstacles 204 and 206, but the number of obstacles is not limited to two and may be more than two. In other embodiments, the plurality of 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.

[0105] 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.

[0106] return Figure 1 The route planning system 100 includes: a planned route acquisition unit 11 that acquires information related to the planned route of the own ship 200 from the route planning unit 2, a moving body information acquisition unit 12 that acquires the position information of the own ship 200 obtained by the GNSS receiver 3, and an obstacle information acquisition unit 13 that acquires obstacle information detected by the sensor 4. In addition, it has an avoidance route acquisition unit 14 that sets an avoidance route for the own ship 200 based on this information.

[0107] 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.

[0108] 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 .

[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] The avoidance route acquisition unit may also acquire avoidance route information generated outside the mobile body via wireless communication such as satellite communication, or may acquire information related to the avoidance route set by the avoidance route setting unit. The avoidance route setting unit includes: an avoidance route candidate plan generation unit that generates one or more avoidance route candidate plans as candidates for the avoidance route, which are different from the planned route between the avoidance start point and the return point on the planned route; and an avoidance route selection unit that selects an avoidance route from the avoidance route candidate plans.

[0111] The avoidance route setting unit includes: a display that displays a nautical chart on which the mobile body is navigating; and a user interface that receives a route set by a user from the nautical chart displayed on the display, and may also acquire information on the set avoidance route.

[0112] Furthermore, the conditions around the ship 200 may be detected at a specified period, and an avoidance path may be set at any time at a specified period. Alternatively, an avoidance path may be set when an obstacle is detected and it is determined that the collision risk value of the obstacle is high.

[0113] Here, the conditions around the ship 200 are detected at a predetermined period, and the avoidance path is set at a predetermined period in the avoidance path setting unit 7. The avoidance path setting unit 7 includes: an avoidance path candidate plan generating unit that automatically generates a avoidance path candidate plan that is a candidate for the avoidance path; and an avoidance path selecting unit that selects an avoidance path from the avoidance path candidate plans according to a predetermined condition, such as evaluating a collision risk value.

[0114] In addition to the above structure, the route planning system 100 of the present invention further includes a collision risk value calculation unit 15, a maximum collision risk value comparison unit 16, and a route change signal 17. The collision risk value calculation unit 15 can be operably connected to the planned route acquisition unit 11, the moving body information acquisition unit 12, and the obstacle information acquisition unit 13 and communicate with them respectively.

[0115] The collision risk value calculation unit 15 receives the planned route 202 as the route of the scheduled navigation, the moving 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. Figures 3 to 7 The calculation of the specific collision risk value will be described in detail later.

[0116] Figure 8 The diagram shows a situation where the ship 200 is sailing on the planned route 202, and other ships 204 and 206 that are obstacles on the planned route 202 are sailing along predicted future paths 208 and 210, respectively, and approaching one after another. If the ship 200 continues to sail along the planned route, the predicted future paths 208 and 210 will interfere with the planned route of the ship 200, and there is a possibility of collision.

[0117] Fig. 9 The diagrams respectively show the change in distance relative to other ships 204 (solid line) and the change in distance relative to other ships 206 (dashed line) when the vessel 200 has sailed for a specified time on the planned route from the avoidance starting point, and the diagrams also show the change in distance relative to other ships 204 (single-dash line) and the change in distance relative to other ships 206 (double-dash line) when the vessel 200 deviates from the planned route at the avoidance starting point and sails on the avoidance path for the same specified time as above.

[0118] When the ship 200 is sailing on the planned route, Figure 8 In the situation shown, since the other ship 204 is approaching, the distance between the two is close. Fig. 9, and then the two move away from each other, so the distance increases. Then, the other ship 206 approaches, but in the closest state, the distance is also greater than that of the other ship 204. That is, the collision risk is small. Therefore, the maximum collision risk value on the planned route is calculated based on the closest state of the other ship 204.

[0119] On the other hand, when the ship 200 is avoiding on the avoidance path, Figure 8 In the situation shown, the other ship 204 is still approaching, and the distance between the two is close, as shown by Fig. 9 The change is shown by the single-point dashed line. This distance is greater than the distance when sailing on the planned route. However, the other ship 206 is approaching, and the closest distance is close to the distance shown by the white circle, which is less than the closest distance to the other ship 204 when the own ship 200 is sailing on the planned route. In other words, the collision risk is large. Therefore, the maximum collision risk value of the avoidance path is calculated based on the closest state of the other ship 206, and this value is greater than the maximum risk value of the planned route.

[0120] return Figure 1 The collision risk value calculation unit 15 is configured to calculate the collision risk value of each object expected to be on the planned route 202 based on the moving body information of the own ship 200 and the obstacle information with respect to the other ships 204 and 206 .

[0121] The collision risk value calculation unit 15 uses a certain location of the ship 200, or the planned route or the current position of the ship 200 as the avoidance starting point, and calculates the collision risk value with the obstacle (other ship) when sailing on the planned route based on the information obtained by the mobile body information acquisition unit 12 and the obstacle information 13. Similarly, the collision risk value is calculated when sailing on the avoidance path for the same specified time using the above-mentioned avoidance starting point as the starting point.

[0122] Furthermore, the route planning system of the present invention further comprises a maximum collision risk value comparison unit 16 which receives the collision risk value from the collision risk value calculation unit 15. The maximum collision risk value comparison unit 16 calculates the maximum value of the collision risk value of each of the planned route and the avoidance path and compares the two.

[0123] The maximum collision risk value comparison unit 16 compares the maximum risk value of the planned route and the maximum risk value of the avoidance path based on the calculated values. In one example of the present embodiment shown here, as described above, the maximum collision risk value of the ship 200 for the other ship 206 on the avoidance path is greater than that of the other ship 204 on the planned route, and therefore, the comparison result is output to the route change signal output unit.

[0124] In addition, referring to Fig. 9In the above description, the vessel 200 starts avoiding navigation from the current position on the planned route, which is taken as the avoidance starting point, but the avoidance starting point is not limited to this. There may be a situation where the actual position on the planned route is inconsistent due to the influence of sea conditions, etc., but this may also be the case.

[0125] In addition, it may not be the current position of the ship 200 but an arbitrary point on the untraveled route of the planned route, or it may be a predicted position calculated based on the moving body information of the ship 200 with the above actual position as the base point.

[0126] Fig.10 This is a diagram showing the relationship between the maximum collision risk value when the ship navigates on the planned route and the maximum collision risk value when the ship navigates on the avoidance path in one embodiment of the route planning system of the present invention.

[0127] Here, three cases are shown. That is, in case 1, the maximum risk value of the planned route is 0.71, and the maximum risk value of the avoidance path is 0.38, which is smaller for the avoidance path. In addition, in case 2, both are 0.52, and in case 3, they are 0.36 and 0.73.

[0128] In case 1, it is shown that the maximum collision risk value of the avoidance path is significantly reduced relative to the maximum collision risk value of the planned route, and the collision risk of navigating on the avoidance path is reduced compared to navigating on the planned route. In case 2, it is shown that since the two values ​​are the same, the collision risk does not change even if the planned route is changed to the avoidance path. In case 3, it is shown that the maximum collision risk value of the avoidance path becomes larger, and the collision risk can be suppressed to a lower level when continuing to navigate on the planned route.

[0129] As described above, the route planning system 100 of the present invention can examine whether the collision risk is reduced by the avoidance route set for the purpose of avoiding obstacles.

[0130] Next, refer to Figures 3 to 7 The figures in the figure illustrate the calculation of the collision risk between the own ship and the obstacle. Figure 3 FIG. 1 shows a scenario of determining a collision risk value associated with an obstacle 204 along a planned route according to an embodiment of the route planning system of the present invention.

[0131] The collision risk value calculation unit 15 calculates the collision risk value for the obstacle 204 based on the moving object information and the obstacle information. Here, the collision risk value for the obstacle 204 is determined based on the positions, moving directions, and speeds of the ship 200 and the obstacle 204.

[0132] The collision risk value calculation unit 15 is configured to 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.

[0133] 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 15 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.

[0134] The collision risk value calculation unit 15 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.

[0135] 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.

[0136] 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 or 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.

[0137] In the present embodiment, the collision risk value calculation unit 15 is configured to further determine the time Tc required for the other ship to reach the closest distance 302. The collision risk value calculation unit 15 further calculates the collision risk value of the obstacle 204 when the host 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.

[0138] If the collision risk value is calculated based on the closest distance Dc between the ship 200 and the obstacle 204, the collision risk value increases even when the time until the ship 200 approaches the obstacle 204 is very long. As a result, the ship 200 may have to deviate from the planned route to avoid a collision with the obstacle 204 after a period of time.

[0139] Therefore, in this embodiment, the collision risk value associated with the obstacle 204 is determined by taking into account the closest distance Dc between the host ship 200 and the obstacle 204 and the time Tc required for other ships to reach the closest point 302 .

[0140] As an example, the collision risk value for the obstacle 204 is calculated and determined based on the following formula (1).

[0141] Collision risk value=max(Dx,Dy)×R Tc (1)

[0142] Figure 4 Also shown are 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. Here, as an example, the collision risk values ​​of the closest distances Dx and Dy in the vertical direction and the horizontal direction are shown.

[0143] Figure 5 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.

[0144] Figure 6The 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.

[0145] 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.

[0146] 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. Figure 7 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.

[0147] In this embodiment, the collision risk value calculation unit 15 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 15 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.

[0148] Figure 7 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.

[0149] 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.

[0150] like Figure 7 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.

[0151] In this embodiment, the collision risk calculation unit 15 determines the time required for the movable body collision avoidance zone 702 to enter the obstacle collision avoidance zone 602 based on the relative speed between the ship 200 and the obstacle 204, the respective speeds of the ship 200 and the obstacle 204, and the distance between the two.

[0152] The collision risk value calculation unit 15 further calculates the collision risk value associated with the obstacle 204 based on the time required for the mobile body collision avoidance area 702 to enter the obstacle collision avoidance area 602. The collision risk value associated with the obstacle 204 may also be calculated using the Figures 6 to 11 The collision risk value associated with the obstacle 204 is determined in the same manner as described in .

[0153] Next, refer to Fig.11 , in addition to the comparison of the maximum collision risk values, the determination of the necessity of route change taking into account the distances from the avoidance start point of the planned route and the avoidance path is described.

[0154] Fig.11 is a block diagram showing the structure of another embodiment of the route planning system 100 of the present invention, and Figure 1 The difference from the structure of the embodiment shown is that it has a distance calculation unit 18. The distance calculation unit 18 obtains information about the route from the planned route acquisition unit 11 and the avoidance path acquisition unit 14, and calculates the distances of the planned route and the avoidance path from the avoidance start point.

[0155] Here, the distance from the avoidance start point may also be calculated for each of the planned route and the avoidance path as the distance traveled by the host ship 200 after a predetermined time has passed since the start of the avoidance. A return point where the host ship 200 returns from the avoidance path may be set on the planned route, and the distance between the avoidance start point and the return point may also be calculated for each of the planned route and the avoidance path.

[0156] As described above, the position of the avoidance start point may be set to the current position of the ship 200 or to a position on an untraveled route of the planned route.

[0157] The calculation result of the above distance is output to the route change signal output unit, and together with the comparison result of the maximum collision risk values ​​of the planned route and the avoidance path output from the maximum collision risk value 16, it is determined whether the route change is necessary.

[0158] Fig.12 and Fig.13 Each of them is a diagram showing the relationship between the maximum collision risk value when the ship navigates on the planned route and the maximum collision risk value when the ship navigates on the avoidance path in another embodiment of the route planning system of the present invention.

[0159] Fig.12 The positions in the diagram showing the relationship between the two are within a preset reference range. Fig.13 The position in the diagram showing the relationship between the two is outside the pre-set reference range. That is, the gray grid portion in the diagram shows an example of a pre-set reference range, and the relationship between the two represented by the black dots is within the reference range. The reference range indicates that the maximum collision risk value of the avoidance path (1) set for the planned route is sufficiently low. If it is within the reference range, it means that in order to ensure higher safety, even if the difference between the congestion risk value described later and the distance between the planned route and the avoidance path (1) is large, it is best to switch the route to the avoidance path (1).

[0160] On the other hand, Fig.13 In the figure, the black dot indicating the relationship between the maximum collision risk value of the planned route and the set avoidance path (2) is located in the lower right area of ​​the figure, i.e., the position where the risk is reduced, but is not within the reference range. In other words, although the maximum collision risk is reduced by changing the route to the avoidance path (2), it cannot be expected to be reduced as much as the avoidance path (1).

[0161] In this case, it is possible to decide not to change the route to the avoidance route (2), but it is also possible to further consider other factors to make the above-mentioned determination on the necessity. Fig.11 In the position implementation method shown, the distance from the avoidance starting point of each of the planned route and the avoidance path to the return point is calculated, which is also determined based on the judgment factor. The effect of reducing the risk brought about by changing the route to the avoidance path (2) is not significant, but it has the advantage of being able to return to the planned route in advance.

[0162] Fig.14 and Fig.15Both show the relationship between the distance on the planned route from the avoidance starting point to the return point of the avoidance path and the distance from the avoidance starting point to the return point of the set avoidance path, that is, the total path length. Fig.14 In the figure, the total path length of the avoidance path (7.2NM) increases by 3.4NM compared to the distance on the planned route (3.8NM), which is a large difference. Fig.15 The results shown are that the distances of the two are roughly the same. Therefore, when the distance increased in this way is small, the avoidance path can also be selected.

[0163] In this embodiment, the case where the ship sails on the planned route and the avoidance path for a specified time from the avoidance start point is used as an example for explanation, but the return point of the ship 200 can also be set in advance on the planned route to calculate the distance for the cases of sailing on the planned route and the avoidance path.

[0164] In addition, in the above case, the distance of the planned route is considered to be shorter than the distance of the avoidance path, but the distance of the avoidance path is sometimes shorter than the distance of the planned route. In this case, if the above conditions are met, it can also be determined to change to the avoidance path.

[0165] Next, refer to Fig.16 and Fig.17 The route planning system of the present invention is described as follows, in which a congestion risk value is considered when determining whether a route change is necessary.

[0166] In this embodiment, if Fig.16 As shown, a congestion risk value calculation unit 19 and a congestion risk value comparison unit 20 are provided, and the result is used for determining whether the route change signal output unit is necessary. Figure 1 The one embodiment shown is structured differently.

[0167] The congestion risk value calculation unit 19 is configured to be operatively connected to the collision risk value calculation unit, communicate with the collision risk value calculation unit 15, and receive Fig.17 A plurality of collision risk values ​​associated with a plurality of obstacles (other vessels) 204 and other obstacles (other vessels) 304 - 312 along the planned route 202 are shown.

[0168] The congestion risk value calculation unit 19 is configured to determine a congestion risk value associated with the planned route 202 along the current path direction based on a plurality of collision risk values. The congestion risk value is based on the collision risk value corresponding to each obstacle included in the obstacles in the congested area, and indicates the degree to which the obstacles included in the congestion risk obstacles are approaching at the same time.

[0169] As an example of calculation corresponding to the plurality of obstacles 204 and obstacles 304 to 312, the congestion risk value calculation unit 19 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. In this embodiment, the congestion risk value calculation unit 19 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 ​​after excluding the maximum collision risk value, that is, the collision risk value for the obstacle 204, from the plurality of collision risk values.

[0170] The "logical sum" mentioned here means that when one or both of the two propositions 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 circuit or the logical sum of binary values. When one or both of the two inputs are 1, the output is 1, and when both are 0, the output is 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). The logical sum of the other three obstacles Obs(1) to Obs(3) is 0.7.

[0171] On the other hand, for obstacles other than the obstacle with the maximum collision risk, the collision risk due to the degree of simultaneous approach, i.e., the congestion risk, is evaluated. To perform this evaluation, for one or more obstacles having collision risk values ​​other than the maximum collision risk value, and 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 19 inputs these collision risk values ​​and calculates the congestion risk value.

[0172] 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.

[0173] However, in the evaluation of the collision risk, it is preferred to calculate the congestion risk value based on the respective collision risk values ​​of one or more other obstacles excluding the obstacle with the maximum collision risk value, and to 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.

[0174] Then, when taking collision avoidance action, other collision risks may be considered, such as the risk of collision with obstacles including the obstacle having the next highest quasi-maximum collision risk value. Fig.16The structure shown is based on such a structure. However, the maximum collision risk value may also be included in the calculation of the congestion risk value.

[0175] In addition, regarding the avoidance routes described so far, Fig.17 In the above, if the positions of the avoidance starting point WP1 and the return point WP4 are also on the planned route 202, each of the avoidance path candidate plans can be set arbitrarily. 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.

[0176] Next, refer to Fig.18 Still another embodiment of the route planning system of the present invention will be described.

[0177] Fig.18 One embodiment of the route planning system of the present invention shown has Fig.11 The distance calculation unit 18 provided in one embodiment shown in FIG. Fig.16 The embodiment shown in the figure includes both the congestion risk value calculation unit 19 and the congestion risk value comparison unit 20. Furthermore, based on the result of the comparison by the maximum risk value comparison unit 16 shown initially, the result of the comparison by the congestion risk value comparison unit 20, and the result of the difference between the distance between the planned route and the avoidance route calculated by the distance calculation unit 18, the route change signal output unit 17 comprehensively determines whether to change the route.

[0178] Fig.19 This is a diagram showing the relationship between the congestion risk value when the ship 200 is navigating on the planned route and the congestion risk value when navigating on the avoidance path. Similar to the maximum collision risk value, the relationship is divided into three categories of 1 to 3 depending on the magnitude of the two values.

[0179] Fig. 20 In the above relationship, the area is divided into a pre-set benchmark range where the degree of improvement in the congestion risk value of the avoidance route relative to the planned route is large, that is, the risk value is greatly reduced, an area where the risk value is reduced although a significant improvement cannot be expected (all in the lower right half), and an upper left area where no improvement can be expected and the risk value is increased.

[0180] For example, the maximum collision risk value of the avoidance path is Fig.12 The congestion risk value is also within the pre-set benchmark area in Fig. 20 When the vehicle is within the preset reference area shown in the lower right corner of the figure, it is possible to make a decision to change the route to the avoidance path regardless of the distance.

[0181] On the other hand, when it is not within the pre-set range and a significant improvement in the collision risk cannot be expected, the difference in distance can be used to determine whether a route change is required. Specifically, although the maximum collision risk value or congestion risk value is improved, if it is an unforeseeable significant improvement, it is possible to return to the planned route early, that is, different types of route plans can be set so that a route change to an avoidance route can be made when encountering a so-called avoidance route that can be returned shortly.

[0182] Table 1 is a table showing an example of type classification for the three evaluation factors of maximum collision risk value, congestion risk value, and difference between the planned route and the avoidance path. In this way, the route planning system of the present invention not only accurately evaluates the collision risk for the avoidance path, but also considers the distance of the avoidance path, thereby flexibly setting the route.

[0183] [Table 1]

[0184]

[0185] *The difference between the distance between the avoidance start point and the return point on the planned path and the distance between the avoidance start point and the return point on the avoidance path

[0186] Therefore, the route planning system 1 of the present invention allows the ship driver, i.e., the operator driving the ship, to avoid 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 of the display unit 6 and the generated avoidance path (avoidance path 212 or other avoidance path), thereby enabling the ship 200 to navigate more safely.

[0187] Reference Fig.21 and Fig. 22 A route planning method based on the route planning structure described so far will be described.

[0188] like Fig.21 As shown, in step 1202, a planned route representing the route from the departure point (or current value) of the mobile body (this ship) to the destination is set or received from the outside, and in step 1204, an avoidance starting point on the planned route of the mobile body (this ship) and an avoidance path with it as the starting point are set or received from the outside.

[0189] In step 1206, the moving body information including the position, moving direction (and speed) of the moving body (this ship) is obtained, and in step 1208, the obstacle information including the position, moving direction (and speed) of one or more obstacles (other ships) is obtained.

[0190] In step 1210, based on the moving body information and obstacle information, the collision risk value of each obstacle (other ship) is calculated for the planned route and the avoidance path respectively. In step 1212, the maximum collision risk value is calculated for the planned route and the avoidance path respectively.

[0191] In step 1214, the maximum collision risk value of the avoidance path is compared with the maximum collision risk value of the planned route to determine whether the collision risk of the avoidance path is significantly improved relative to the planned route, that is, whether the maximum collision risk value is reduced to or above the prescribed level, and the degree of improvement is determined. If it is improved, the process proceeds to step 1222 and directly outputs a route switching signal for changing the route to the avoidance path. Through this switching signal, a display showing the route plan of the ship can be used to notify this, and direct navigation control such as controlling the steering can also be performed based on the signal.

[0192] On the other hand, in step 1216, if the maximum collision risk value of the avoidance path is greater than the maximum collision risk value of the planned route and no collision risk is reduced, the avoidance path is not adopted and the process ends directly.

[0193] If the maximum collision risk value of the avoidance path is equal to or less than the maximum collision risk value of the planned route, in step 1218, the congestion risk value of the avoidance path is compared with the congestion risk value of the planned route. If it is greatly improved, that is, it is within the specified reference area, a route change signal is directly output to change the route to the avoidance path.

[0194] On the other hand, even in the case where there is no significant improvement in the congestion risk value, in step 1220, the distance between the planned route and the avoidance path is compared, and the difference or ratio is calculated, and if it is within a specified range, a route change signal is output to change the route to the avoidance path.

[0195] 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.

[0196] 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.

[0197] 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.

[0198] 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.

[0199] 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 that acquires obstacle information including a position and a moving direction for each of a plurality of obstacles existing around the moving body; an avoidance route acquisition unit, which acquires avoidance route information indicating an avoidance route different from the planned route, taking the avoidance start point at which the mobile body starts avoidance as a starting point; 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 maximum collision risk value comparison unit, which compares a planned route maximum collision risk value and an avoidance path maximum collision risk value, wherein the planned route maximum collision risk value is the maximum collision risk value among the collision risk values ​​when the mobile body is navigating on the planned route with the avoidance start point as the starting point, and the avoidance path maximum collision risk value is the maximum collision risk value among the collision risk values ​​when the mobile body is navigating on the avoidance path with the avoidance start point as the starting point; as well as The route change signal output unit outputs a route change signal for instructing a route change to the avoidance route when the maximum collision risk value of the avoidance route is lower than the maximum collision risk value of the planned route.

2. The route planning system according to claim 1, wherein: The avoidance start point is the current navigation position of the mobile body moving on or along the planned route.

3. The route planning system according to claim 1, wherein: The avoidance start point is an arbitrary position on a non-navigated route on the planned route or a future position of the moving body calculated with the current navigation position of the moving body moving along the planned route as a base point.

4. The route planning system according to claim 1, wherein: The method further comprises: a distance calculation unit for calculating the distance when the mobile body sails on the planned route for a specified time from the avoidance starting point, and the distance when the mobile body sails on the avoidance path for a specified time from the avoidance starting point, respectively. The route change signal output unit further determines whether it is necessary to output the route change signal based on the distance on the planned route and the distance on the avoidance path.

5. The route planning system according to claim 4, wherein: The route change signal output unit calculates a difference between a distance on the planned route and a distance on the avoidance path, and outputs the route change signal when the difference is equal to or smaller than a predetermined value.

6. The route planning system according to claim 4, wherein: The route change signal output unit calculates a ratio of a distance on the avoidance route to a distance on the planned route, and outputs the route change signal when the ratio is equal to or less than a predetermined value.

7. The route planning system according to any one of claims 4 to 6, wherein: The route change signal output unit outputs the route change signal when the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is within a preset reference range, The route change signal output unit determines whether to output the route change signal based on the distance on the planned route and the distance on the avoidance path when the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is outside the reference range.

8. The route planning system according to claim 7, wherein: The moving object information further includes information related to the speed of the moving object.

9. The route planning system according to claim 8, wherein: The obstacle information also includes information related to the speed of the obstacle.

10. The route planning system according to claim 1, wherein: Also features: 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 obstacles included in the congestion risk obstacle based on a collision risk value corresponding to each obstacle included in the congestion risk obstacle; as well as a congestion risk value comparison unit, which compares a planned route congestion risk value and an avoidance path congestion risk value, wherein the planned route congestion risk value is the congestion risk value when the mobile body is navigating on the planned route with the avoidance start point as the starting point, and the avoidance path congestion risk value is the congestion risk value when the mobile body is navigating on the avoidance path with the avoidance start point as the starting point, The route change signal output unit instructs a route change to the avoidance route when the maximum collision risk value of the avoidance route is lower than the maximum collision risk value of the planned route and the congestion risk value of the avoidance route is lower than the congestion risk value of the planned route.

11. The route planning system according to claim 10, wherein: The avoidance start point is the current navigation position of the mobile body moving on or along the planned route.

12. The route planning system according to claim 10, wherein: The avoidance start point is an arbitrary position on a non-navigated route on the planned route or a future position of the moving body calculated with the current navigation position of the moving body moving along the planned route as a base point.

13. The route planning system according to claim 10, wherein: The method further comprises: a distance calculation unit for calculating the distance when the mobile body sails on the planned route for a specified time from the avoidance starting point, and the distance when the mobile body sails on the avoidance path for a specified time from the avoidance starting point, respectively. The route change signal output unit further determines whether it is necessary to output the route change signal based on the distance on the planned route and the distance on the avoidance path.

14. The route planning system according to claim 13, wherein: The route change signal output unit calculates a difference between a distance on the planned route and a distance on the avoidance path, and outputs the route change signal when the difference is equal to or smaller than a predetermined value.

15. The route planning system according to claim 14, wherein: The route change signal output unit calculates a ratio of a distance on the avoidance route to a distance on the planned route, and outputs the route change signal when the ratio is equal to or less than a predetermined value.

16. The route planning system according to any one of claims 13 to 15, wherein: The route change signal output unit outputs the route change signal when the relationship between the congestion risk value of the planned route and the congestion risk value of the avoidance route is within a preset reference range, The route change signal output unit determines whether to output the route change signal based on the distance on the planned route and the distance on the avoidance path when the relationship between the congestion risk value of the planned route and the congestion risk value of the avoidance path is outside the reference range.

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

18. The route planning system according to claim 17, wherein: The obstacle information also includes information related to the speed of the obstacle.

19. The route planning system according to claim 18, 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.

20. The route planning system according to claim 19, 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.

21. The route planning system of claim 20, 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.

22. The route planning system of claim 21, 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.

23. The route planning system of claim 21, 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.

24. The route planning system according to any one of claims 1, 10 to 15, wherein The avoidance route acquisition unit acquires the avoidance route information from the avoidance route setting unit, The avoidance path setting unit comprises: an avoidance route candidate plan generating unit that generates 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 untraveled route and a return point set on the planned route where the mobile body returns; and The avoidance path selection unit selects an avoidance path from among the avoidance path candidate proposals.

25. The route planning system of claim 24, 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 along the avoidance route candidate plan. The avoidance route selection unit selects an avoidance route candidate as the avoidance route based on the maximum collision risk value.

26. The route planning system of claim 25, wherein: The congestion risk calculation unit calculates the congestion risk value for each of the one or more avoidance route candidate solutions. The avoidance route acquisition unit sets the avoidance route based on the maximum collision risk value and the congestion risk value.

27. The route planning system according to any one of claims 1, 10 to 15, 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.

28. The route planning system according to any one of claims 1, 10 to 15, wherein: The obstacle information also includes information related to other objects including at least one of other ships, currents, weather, reefs, and stranded ships.

29. The route planning system according to any one of claims 1, 10 to 15, wherein: The device further comprises: a display for displaying the avoidance path together with the planned route on a display image.

30. The route planning system according to any one of claims 1, 10 to 15, 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.

31. The route planning system according to any one of claims 1, 10 to 15, wherein The avoidance route acquisition unit acquires the avoidance route information generated outside the mobile body via wireless communication.

32. The route planning system according to any one of claims 1, 10 to 15, wherein The avoidance route acquisition unit acquires the avoidance route information from the avoidance route setting unit, The avoidance path setting unit comprises: a display for displaying a nautical chart on which the mobile body is navigating; and The user interface receives a route set by a user from the nautical chart displayed on the display.

33. A route planning method, which plans a route from a departure point to a destination, wherein: acquiring planned route information indicating a planned route of a mobile object moving on water; Acquiring moving object information including the position and moving direction of the moving object; Obtaining obstacle information including a position and a moving direction for each of a plurality of obstacles existing around the moving object; Taking the avoidance start point where the mobile body starts to avoid flight as a starting point, obtaining an avoidance path different from the planned route; For 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, respectively calculate the maximum collision risk value among the collision risk values ​​when the mobile body is navigating on the planned route with the avoidance starting point as the starting point, i.e., the maximum collision risk value of the planned route, and the maximum collision risk value among the collision risk values ​​when the mobile body is navigating on the avoidance path with the avoidance starting point as the starting point, i.e., the maximum collision risk value of the avoidance path; The maximum collision risk value of the planned route is compared with the maximum collision risk value of the avoidance path, and when the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route, a route change signal indicating a route change to the avoidance path is output.

34. The route planning method according to claim 33, wherein: The distance of the mobile body when it sails on the planned route for a specified time from the avoidance starting point is calculated, and the distance of the mobile body when it sails on the avoidance path for a specified time from the avoidance starting point is calculated, Whether the route change signal needs to be output is also determined based on the distance on the planned route and the distance on the avoidance path.

35. The route planning method according to claim 34, wherein: outputting the route change signal when the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is within a preset reference range, When the relationship between the maximum collision risk value of the planned route and the maximum collision risk value of the avoidance path is outside the reference range, whether the route change signal needs to be output is determined based on the distance on the planned route and the distance on the avoidance path.

36. The route planning method according to claim 33, wherein: further calculating a congestion risk value indicating a 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 for the congestion risk obstacle including the plurality of obstacles; Calculating the congestion risk value of the planned route with the avoidance starting point as the starting point on the planned route, calculating the congestion risk value of the avoidance path with the avoidance starting point as the starting point on the avoidance path, Compare the congestion risk value of the planned path and the congestion risk value of the avoidance path. In the case where the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route and the congestion risk value of the avoidance path is lower than the congestion risk value of the planned route, a route change to the avoidance path is indicated.

37. The route planning method according to claim 33 or 36, wherein: A return point for the mobile body to return is also set on the planned route, and a distance on the planned route between the avoidance start point and the return point, and a distance on the avoidance path between the avoidance start point and the return point on the avoidance path are calculated respectively. Based on the distance on the planned route and the distance on the avoidance path, it is determined whether the route change signal needs to be output.

38. 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 object moving on water; Acquiring moving object information including the position and moving direction of the moving object; Obtaining obstacle information including a position and a moving direction for each of a plurality of obstacles existing around the moving object; Taking the avoidance start point where the mobile body starts to avoid flight as a starting point, obtaining an avoidance path different from the planned route; For 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, respectively calculate the maximum collision risk value among the collision risk values ​​when the mobile body is navigating on the planned route with the avoidance starting point as the starting point, i.e., the maximum collision risk value of the planned route, and the maximum collision risk value among the collision risk values ​​when the mobile body is navigating on the avoidance path with the avoidance starting point as the starting point, i.e., the maximum collision risk value of the avoidance path; The maximum collision risk value of the planned route is compared with the maximum collision risk value of the avoidance path, and when the maximum collision risk value of the avoidance path is lower than the maximum collision risk value of the planned route, a route change signal indicating a route change to the avoidance path is output.

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