This application claims priority to Taiwan Application Serial Number 107135444, filed on Oct. 8, 2018, which is herein incorporated by reference.
Present disclosure relates to a navigation system and a navigation method. More particularly, present disclosure relates to a navigation system and a navigation method for ships.
In conventional arts, A* search algorithms are widely used in marine navigation. The known A* search algorithms can be used to find a shortest path for a ship to get away from obstacles (e.g. lands or islands). However, A* search algorithms being used in conventional arts can sometimes provide lanes that are closed to shores. The A* search algorithms being used in conventional arts can also provide unideal lanes that are restricted by obstacles. Therefore, improvements to current navigation systems are required.
An aspect of present disclosure relates to a ship navigation system. The ship navigation system comprises a memory and a processor. The memory is configured to store at least one instruction. The processor is coupled to the memory. The processor is configured to access the at least one instruction to perform the following operations: receiving a start point of a target ship and a terminal point of the target ship in a marine area; receiving real-time environmental data of the marine area, a plurality of historical lanes in the marine area and historical environmental data corresponding to the plurality of historical lanes; comparing the historical environmental data with the real-time environmental data to select a target lane from the historical lanes, wherein the target lane is leading from a location near the start point to a location near the terminal point; and connecting the start point and the terminal point with the target lane to generate an recommended lane for the target ship in the marine area.
Another aspect of disclosure relates to a ship navigation method. The ship navigation method is performed by a processor according to at least one instruction accessed from a memory. The ship navigation method comprising: receiving a start point of a target ship and a terminal point of the target ship in a marine area; receiving real-time environmental data of the marine area, a plurality of historical lanes in the marine area and historical environmental data corresponding to the plurality of historical lanes; comparing the historical environmental data with the real-time environmental data to select a target lane from the historical lanes, wherein the target lane is leading from a location near the start point to a location near the terminal point; and connecting the start point and the terminal point with the target lane to generate an recommended lane for the target ship in the marine area.
In some embodiments, the processor is further configured to access the at least one instruction to perform following steps: receiving a real-time position and a direction of a plurality of surrounding ships in the marine area; estimating whether the recommended lane is blocked by the plurality of surrounding ships according to the real-time positions and the directions of the plurality of surrounding ships; and in response to the recommended lane being estimated to be blocked by the plurality of surrounding ships, modifying the recommended lane to a modified lane.
In some embodiments, the processor estimating whether the recommended lane is blocked by the plurality of surrounding ships according to the real-time positions and the directions of the plurality of surrounding ships further comprising: extending a safety distance from the real-time positions of the plurality of surrounding ships, in order to generate a plurality of obstacle zones according to the directions of the plurality of surrounding ships; estimating whether the recommended lane encounters the plurality of obstacle zones; and in response to the recommended lane being estimated to encounter the plurality of obstacle zones, determining that the recommended lane is blocked by the plurality of surrounding ships.
In some embodiments, the processor comparing the historical environmental data with the real-time environmental data to select the target lane from the historical lanes further comprising: calculating a plurality of difference levels between the historical environmental data corresponding to each of the historical lanes and the real-time environmental data, in order to select at least one first candidate lane from the historical lanes according to the plurality of difference levels; and selecting the target lane from the at least one first candidate lane.
In some embodiments, the processor calculating the plurality of difference levels to select the at least one first candidate lane further comprising: selecting a first lane from the historical lanes; obtaining a historical parameter set from the historical environmental data corresponding to the first lane and obtaining a real-time parameter set from the real-time environmental data corresponding to the historical parameter set; calculating a difference between the real-time parameter set and the historical parameter set corresponding to the first lane; determining whether the difference corresponding to the first lane exceeds a predetermined threshold; if the difference corresponding to the first lane is determined to exceed the predetermined threshold, removing the first lane from the historical lanes; and if the difference corresponding to the first lane is determined not to exceed the predetermined threshold, selecting the first lane to be the at least one first candidate lane.
In some embodiments, the processor selecting the target lane from the at least one first candidate lane further comprising: counting a plurality of way points corresponding to each of the at least one first candidate lane; selecting the at least one first candidate lane having the least way points and determining whether a number of the at least one first candidate lane being selected exceeds one; and if the number of the at least one first candidate lane being selected is determined not to exceed one, confirming that the at least one first candidate lane being selected to be the target lane.
In some embodiments, if the number of the at least one first candidate lane being selected is determined to exceed one, the processor is further configured to access the at least one instruction to perform the following: selecting the at least one first candidate lane having the least way points to be a plurality of second candidate lanes; depicting a selection frame in the marine area, wherein the start point of the target ship and the terminal point of the target ship are located at two corners of the selection frame respectively; targeting a first intersection and a second intersection that each of the plurality of second candidate lanes crossing the selection frame; calculating a first distance between the first intersection and the start point and a second distance between the second intersection and the terminal point; calculating a sum of the first distance and the second distance corresponding to each of the plurality of second candidate lanes; and selecting a second lane from the plurality of second candidate lanes, wherein the sum of the second lane is the least among the plurality of second candidate lanes.
In some embodiments, the historical parameter set comprises at least one of a wind direction, a wind speed, a current direction and a current speed, and the real-time parameter set comprises at least one of the wind direction, the wind speed, the current direction and the current speed.
In some embodiments, the processor generating the recommended lane for the target ship in the marine area further comprising: connecting a lead-in lane from the start point to the target lane; connecting a lead-out lane from the target lane to the terminal point; and applying a curve fitting process to the lead-in lane, the lead-out lane and the target lane to generate the recommended lane.
According to above aspects and embodiments, the ship navigation system and the ship navigation method can be used to select one of the historical lanes according to the real-time environmental data and the historical environmental data, and connect the selected historical to the start point and the terminal point of the target ship to gain the recommended lane. The recommended lane generated according to present disclosure can be safely kept away from the shore. In this manner, an efficient navigation process can be provided.
Reference will now be made in detail to the present embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
In the following description and claims, unit being described with singulars, such as “one”, “the”, “that”, and “this” are not intend to limited the numbers of the described unit.
In the following description and claims, the terms “first”, “second”, and the like are not intend to limit a specific order of the units being described.
In the following description and claims, the terms “coupled” and “connected”, along with their derivatives, may be used. In particular embodiments, “connected” and “coupled” may be used to indicate that two or more elements are in direct physical or electrical contact with each other, or may also mean that two or more elements may be in indirect contact with each other. “Coupled” and “connected” may still be used to indicate that two or more elements cooperate or interact with each other.
As used herein, the terms “comprising,” “including,” “having,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to.
In the following description and claims, the term “and/or” may be used to describe one of a plurality things or a combination or said things.
In the following description and claims, some of the directions “up”, “down”, “before, “after” and the like can be considered as references along with the figures. The scope of present disclosure should not be limited thereto.
The terms used in this specification generally have their ordinary meanings in the art and in the specific context where each term is used. The use of examples in this specification, including examples of any terms discussed herein, is illustrative only, and in no way limits the scope and meaning of the disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given in this specification.
In some embodiments, except the at least one instruction, the memory 120 can store (or temporarily store) other necessary data for the processor 140 to perform the applications, or store (or temporarily store) data generated by the processor 140 in such applications.
As shown in
In some embodiments, the ship navigation system 100 is settled on a ship. The ship can be a large vessel such as a battle ship, a cruise, or a ferry. The ship can be a small ship such as a fishing ship or a motor boat. The ship can also be an automated ship such as an automated observing ship or an automated patrol ship. In some embodiments, the ship navigation system 100 is not settled on a ship but communicatively coupled to some electrical devices on the ship. The ship navigation system 100 can apply unidirectional or bidirectional information transmission with the electrical devices on the ship. Therefore, in these embodiments, the ship navigation system 100 can determine a recommended lane for the ship in some marine areas, which is, to navigate the ship in these marine areas.
In step S210: receiving a start point of a target ship and a terminal point of the target ship in a marine area.
In some embodiments, the ship navigation system 100 includes the interaction interface 160. The processor 140 can access a map of the marine area from the memory 120. The processor 140 can send the map to the interaction interface 160 thereon the map of the marine area is displayed. For better understandings, reference is made to
In some embodiments, the users can enter a start point SP of the target ship and a terminal point TP of the target ship in the marine area OCE via the input interface (e.g. touch display) of the interaction interface 160. As shown in
In some embodiments, the users can enter the start point SP of the target ship and the terminal point TP of the target ship in the marine area OCE via the input interface (e.g. keyboards) of the interaction interface 160. For instance, the users can input longitudes and latitudes of the start point SP and the terminal point TP, and the output interface of the interaction interface 160 can display the positions of the start point SP and the terminal point TP in the marine area OCE.
In some embodiments, the start point SP of the target ship and the terminal point TP of the target ship in the marine area OCE has being stored in the memory 120 in advance, the processor 140 can access the start point SP of the target ship and the terminal point TP of the target ship from the memory 120. The processor 140 can further send the map of the marine area OCE, the start point SP of the target ship and the terminal point TP of the target ship to the interaction interface 160, and the interaction interface 160 can display the map of the marine area OCE, the start point SP of the target ship and the terminal point TP of the target ship via the output interface.
In step S220: receiving real-time environmental data of the marine area.
In some embodiments, the ship navigation system 100 can be communicatively coupled to a weather server (not shown). In this case, the processor 140 of the ship navigation system 100 can obtain real-time environmental data in the marine area OCE from the weather server. It is noted that the real-time environmental data here refer to some environmental parameters that can possibly influence ship sailings, such as wind directions, wind speeds, current directions and current speeds in every sub areas of the marine area OCE.
In step S230: receiving a plurality of historical lanes in the marine area and historical environmental data corresponding to the plurality of historical lanes.
In some embodiments, the ship navigation system 100 can be communicatively coupled to a ship management server (not shown). The ship management server is communicatively coupled to automatic identification systems (AIS) of a plurality of ships in the marine area OCE to collect data of these ships around the target ship. Said data can be identification codes, names, positions, directions, speed, and captains of these ships. In this case, the processor 140 of the ship navigation system 100 can obtain the data of other ships in the marine area OCE from the ship management server. It is noted that a method for the ship navigation system 100 to retrieve the data from the automatic identification systems is known to person skilled in the art thus it would not be discussed in this document.
As mentioned, the ship management server is communicatively coupled to the automatic identification systems settled on the ships in the marine area OCE in order to collect data of the ships, including positions, directions, and speeds. By accumulating the collected data, the ship management server can obtain lane of the ships in the marine area OCE, so called the historical lanes of the ships in the marine area OCE.
Similarly, the weather server can retrieve the real-time environmental data in the marine area OCE, including wind directions, wind speeds, current directions and current speeds in every sub areas of the marine area OCE. By accumulating the collected data, the weather server can obtain long-term environmental data in the marine area OCE, so called the historical environmental data of the marine area OCE.
In some embodiments, the ship navigation system 100 can be communicatively coupled to the ship management server and the weather server to retrieve the historical lanes of the ships in the marine area OCE and the historical environmental data in the marine area OCE. In some embodiments, the processor 140 of the ship navigation system 100 can send electrical signal carrying said data to the interaction interface 160, and the interaction interface 160 can output said data via the output interface. For example, the interaction interface 160 can display the historical lanes of the ships in the marine area OCE and the historical environmental data in the marine area OCE on the map of the marine area OCE. For better understanding, reference is made to
In step S240: comparing the historical environmental data with the real-time environmental data to select a target lane from the historical lanes, wherein the target lane is leading from a location near the start point to a location near the terminal point.
In some embodiments, the processor 140 of the ship navigation system 100 can select some historical lanes leading from a region around the start point SP of the target ship to a region around the terminal point TP of the target ship. For better understandings, referring to
As mentioned, in some embodiments, the ship navigation system 100 can be communicatively coupled to the ship management server and the weather server to retrieve the historical lanes of the ships in the marine area OCE and the historical environmental data in the marine area OCE. Since the processor 140 of the ship navigation system 100 is provided to navigate the target ship in real-time, the processor 140 can compare the real-time environment with the historical environmental data in order to choose some historical lanes under similar environment. For better understandings, referring to
In some embodiments, after the processor 140 selects some historical lanes substantially leading from somewhere around the start point SP to somewhere around the terminal point TP (as shown in the embodiment of
In some embodiments, the processor 140 can calculate dissimilarities between the real-time parameter set and the historical parameter set. For instance, in a case that the wind directions in marine area OCE are recorded in circular angles (360° in total), the processor 140 can calculate differences between angles of the wind direction extracted in each historical environmental datum and each real-time environmental datum. In some embodiments, in a case that the parameter sets being selected include multiple environmental parameters, the processor 140 can calculate differences between each parameter from the historical environmental data and the real-time environmental data.
In some embodiments, the differences between the environmental parameters can be compared with a predetermined threshold. If a difference between a historical environmental datum and the real-time environmental datum is being determined exceeding the predetermined threshold, the processor 140 can delete a historical lane corresponding to that historical environmental datum. It is noted that the predetermined threshold can be set by the users or be set by the processor 140 according to statistics of the historical environmental data. For example, in some embodiments, if a standard deviation of the wind directions in the historical environmental data is calculated as 2.5 degrees, the processor 140 can calculate a difference between the wind speed corresponding to each historical environmental datum and the wind speed corresponding to each real-time environmental datum. Once a difference of the wind speeds exceeding 2.5 degrees is found, the processor 140 can delete a historical lane corresponding to such difference since it is apparent that this historical environmental datum is not matched to the real-time wind speed in the marine area OCE. In this manner, the processor 140 can apply such selection to generate at least one first candidate lane from the historical lanes. It is noted that, after such selection, the at least one candidate lane being selected from the historical lanes is substantially matched to the real-time environment data in the marine area OCE.
For better understandings, reference is made to
It is noted that, in conventional arts, shipping lanes are mostly generated according to the known A* search algorithm. In a navigation system using the A* search algorithm, a plurality of way points in the marine area OCE are searched in a specific order to form a shipping lane. The way points can be understood as some positions (e.g. coordinates determined by longitude and latitude in the marine area OCE) that are available for a ship to sail in the marine area OCE. According to the A* search algorithm, the way points available to the ship are searched and determined one by one. Then, the way points are connected to form the lane for the ship. In addition, some conventional arts are provided to optimize the lanes by reducing some redundant way points after the searching is completed.
For better understandings, referring to
In some embodiments, the processor 140 of the ship navigation system 100 can further apply a selection to the at least one first candidate lanes according to number of way points. For better understandings, reference is made to
As shown in the embodiment of
In some embodiments, the processor 140 of the ship navigation system 100 can further check the at least one second candidate lane according to distances. For better understandings, referring to
Similarly, two intersections of the historical lane CP2 and the selection frame SF are shown in
In step S250: generating a recommended lane for the target ship in the marine area by connecting the start point and the terminal point with the target lane.
In some embodiments, after the processor 140 determines the target lane from the at least one second candidate lanes, the target lane can be connected to the start point SP and the terminal point TP of the target ship to generate a recommended lane for the target ship in the marine area OCE. In one embodiment, the processor 140 can generate the recommended lane according to a specific search algorithm. In some embodiments, the specific search algorithm can be an improved A* search algorithm for guiding the target ship from the start point SP to the terminal point TP via the target lane.
In some embodiments, locations in the marine area OCE can be represented as nodes with longitudes and latitudes. A cost function of the specific search algorithm can be used to find a cost of each node in the marine area OCE. Through the specific search algorithm, several way points can be found by lowering a sum of costs of the nodes being searched to a minimal cost. A lane formed by these way points can therefore be determined. The weight function is represented as:
f(n)=g(n)+h(n)+w(n).
In the cost function, g(n) is a function for calculating a real distance from a node to the start point SP of the target ship in the marine area OCE. The result of g(n) can be obtained by summing a distance from a parent node of the node to the start point SP and an Euclidean distance from the parent node to the node. In the cost function, h(n) is a function for calculating an estimated distance from node to the terminal point TP of the target ship in the marine area OCE. The result of h(n) can be obtained by calculating a Manhattan distance from the node to the target ship. In the cost function, w(n) is a function for calculating a weight of the node with respect to the target lane (i.e. the historical lane CP2 in above embodiment). The result of w(n) can be obtained by calculating a shortest distance from the node to the target lane. It is noted that, in a search according to the specific search algorithm, the result of w(n) can be gradually reduced.
For better understandings, reference is made to
In some embodiments, the processor 140 can further apply a curve fitting process to these lanes to gain the recommended lanes. For example, in some embodiments, after the processor 140 gets the lead-in lane INL and the lead-out lane OUL, the processor 140 can connect the lead-in lane INL to the historical lane CP2 and connect the historical lane CP2 to the lead-out lane OUL. Then, redundant lanes before the lead-in intersection and after the lead-out intersection on the historical lane CP2 can be deleted. In this way, the processor 140 can generate a raw recommended lane RRL. The curve fitting process can be applied to the way points on the raw recommended lane RRL. For better understandings, referring to
In step S260: receiving a real-time position of a plurality of surrounding ships and a direction of the plurality of surrounding ships, then estimating whether the recommended lane being blocked by the plurality of surrounding ships according to the real-time position and the direction of the plurality of surrounding ships, and in response to the recommended lane being estimated to be blocked by the plurality of surrounding ships, modifying the recommended lane to a modified lane.
As mentioned, in some embodiments, the ship navigation system 100 can be communicatively coupled to the ship management server to receive data of other ships in the marine area OCE. In some embodiments, when the processor 140 of the ship navigation system 100 receives the real-time environmental data and data of other ships in the marine area OCE, the processor 140 can send electric signals carrying the data to the interaction interface 160 and the interaction interface 160 can display the data via the output interface. For example, the interaction interface 160 can show mentioned data on the map of the marine area OCE. For better understandings, reference is made to
In some embodiments, the users can select some of the six ships S1-S6 in the marine area OCE via the input interface of the interaction interface 160, and the interaction interface 160 can show data of these six ships S1-S6 in some information blocks. In some embodiments, the users can select some locations (coordinates determined by longitudes and latitudes) in the marine area OCE, and the interaction interface 160 can show real-time environmental data corresponding to these locations in some information blocks.
In some embodiments, the ship navigation system 100 can be communicatively coupled to the ship management server to receive data of other ships in the marine area OCE, especially the real-time positions, directions and speeds of these ships. In some embodiments, according to the real-time positions, directions and speeds of these ships, the processor 140 of the ship navigation system 100 can estimate whether the final recommended lane FRL can be blocked by some of these ships. In some embodiments, the processor 140 can generate a safety circle of a ship by extending a safety distance (e.g. according to length of the ship) from its real-time position. Along with the direction and the speed of the ship, the safety circle can depict an obstacle zone corresponding to that ship in the marine area OCE.
In some embodiments, after the processor 140 depicts the obstacle zones corresponding to other ships in the marine area OCE, it can be estimated if the final recommended lane FRL may pass these obstacle zones. The estimation can be established according to algorithms built on Kalman Filter, particle filter, or structured tracking with kernel, etc. If it is determined that the recommended lane may pass these obstacle zones, collisions between the target ship and some of these ships may happened. The processor 140 is configured to modify the recommended lane to avoid such collisions. For better understandings, referring to
In some embodiments, when the processor 140 of the ship navigation system 100 generates the modified recommended lane MRL according to the ship navigation method 200, the processor 140 can navigate the target ship according to the modified recommended lane MRL. Thus, the target ship should be driven in the marine area OCE along the modified recommended lane MRL. However, it is noted that the ship navigation method 200 can be operated in a dynamic mode. When the target ship is sailing in the marine area OCE along the modified recommended lane MRL, it is possible that the ship navigation method 200 being executed for several times according to the environment and other ships in the marine area OCE.
It is noted that, basically, the interaction interface 160 shows each steps of the ship navigation method 200 described in the embodiments of
According to forgoing embodiments, present disclosure provides the ship navigation system and the ship navigation method. Based on such system and method, some idea lanes matched to current environment can be selected from the historical lanes. The target ship can be navigated from the start point to the terminal point via the selected lane. Moreover, the ship navigation system and the ship navigation method can be operated dynamically to adapt moves of other ships. In this way, accidents between ships can be avoided.
Although the present disclosure has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims.
Number | Date | Country | Kind |
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107135444 | Oct 2018 | TW | national |