CN117805877A

CN117805877A - Marine positioning method and device, electronic equipment and storage medium

Info

Publication number: CN117805877A
Application number: CN202410233046.1A
Authority: CN
Inventors: 毛刚; 刘俊强; 贾明江; 吕延兵; 周健
Original assignee: Beijing Zhihui Space Technology Co ltd
Current assignee: Beijing Zhihui Space Technology Co ltd
Priority date: 2024-03-01
Filing date: 2024-03-01
Publication date: 2024-04-02
Anticipated expiration: 2044-03-01
Also published as: CN117805877B

Abstract

The application provides a marine positioning method, a marine positioning device, electronic equipment and a storage medium, wherein the method comprises the following steps: calculating a first actual navigational speed of the target ship according to the satellite positioning data; acquiring navigational speed influence data of a target ship, wherein the navigational speed influence data is data of various factors influencing navigational speed of the target ship; calculating a plurality of first predicted speeds of the target ship in a preset first time period through each speed influence data and an initial weight value of a corresponding influence weight; determining and calculating target weight values corresponding to the respective influence weights when the first predicted speed which is the same as the first actual speed exists in the plurality of first predicted speeds; and when the satellite positioning data cannot be acquired, determining the positioning of the target ship through the calculated second predicted navigational speed of the target ship based on the acquired navigational speed influence data and the target weight value. The marine positioning method and the marine positioning device can perform marine positioning when the ship cannot receive signals of the global navigation satellite system.

Description

Marine positioning method and device, electronic equipment and storage medium

Technical Field

The application relates to the technical field of ship positioning, in particular to a ship positioning method, a ship positioning device, electronic equipment and a storage medium.

Background

Marine vessel transportation is an activity for transporting goods and personnel on the ocean using various types of vessels, and is an integral part of global trade and economic activities. This mode of transportation is distinguished by its cost effectiveness, high carrying capacity and particular suitability for bulk goods. Sea transportation can be divided into bulk cargo transportation, container transportation, tanker transportation and other forms to serve different kinds of cargo. Shipping not only connects ports around the world, but also the primary means of international trade and resource allocation. However, marine vessels transport at relatively slow speeds and are greatly affected by weather and marine environments.

At present, the positioning of a ship during offshore navigation mainly depends on a Global Navigation Satellite System (GNSS), but due to the natural vulnerability of signals of the global navigation satellite system and the fact that the signals cannot completely cover all the surfaces of the earth, the ship cannot be positioned through the global navigation satellite system at a certain time during navigation, so that the navigation accuracy is affected. There is a need for a method to enable offshore positioning when a vessel is unable to receive signals from the global navigation satellite system.

Disclosure of Invention

The application provides a marine positioning method, a marine positioning device, an electronic device and a storage medium, which can perform marine positioning when a ship cannot receive signals of a global navigation satellite system.

In a first aspect of the present application, there is provided a method of marine positioning, the method comprising:

acquiring satellite positioning data for a target ship;

calculating a first actual navigational speed of the target ship according to the satellite positioning data, wherein the first actual navigational speed is the actual navigational speed of the target ship;

acquiring navigational speed influence data of the target ship, wherein the navigational speed influence data is data of various factors influencing navigational speed of the target ship;

calculating a plurality of first predicted speeds of the target ship in a preset first time period through each speed influence data and an initial weight value of a corresponding influence weight;

determining and calculating a target weight value corresponding to each influence weight when a first predicted speed identical to the first actual speed exists among the plurality of first predicted speeds;

and when the satellite positioning data cannot be acquired, determining the positioning of the target ship through the calculated second predicted navigational speed of the target ship based on the acquired navigational speed influence data and the target weight value.

By adopting the technical scheme, the marine positioning can be performed when the ship cannot receive the Global Navigation Satellite System (GNSS) signal, because the marine positioning system does not depend on satellite positioning data only, but combines various navigational speed influencing factors to calculate the predicted navigational speed of the ship. Specifically, this scheme first calculates the actual speed of the ship when it is able to receive satellite positioning data, and collects data of various factors affecting the speed. Then, a predicted voyage is calculated from the data and the corresponding impact weights. In the process, the weight value of each factor affecting the navigational speed is determined, the predicted navigational speed is matched with the actual navigational speed, the accurate weight value affecting the weight is determined, the weight of each factor affecting the navigational speed is equivalent to the weight of each factor affecting the navigational speed, and the follow-up more accurate predicted navigational speed is facilitated. When the ship cannot receive the satellite signals, a second predicted navigational speed is calculated through the weight value determined before and the acquired navigational speed influence data. Since these influencing factors and weight values have been calibrated according to the actual speed, the second predicted speed may more accurately reflect the motion state of the vessel. Based on this predicted voyage speed and the known last satellite positioning point, the current position of the vessel in the absence of satellite signals can be estimated. In summary, by integrating a number of factors affecting the speed of the ship and utilizing a previously calibrated data model, the position of the ship can be effectively predicted even in the event that GNSS signals cannot be received.

Optionally, the calculating, by using each of the voyage impact data and the initial weight value of the corresponding impact weight, a plurality of first predicted voyages of the target ship within a preset first time period, specifically by using the following formula:

；

wherein V is _r For the first predicted speed, deltaV, for the preset first period of time _p For the theoretical navigational speed of the power output of the ship in the preset first time period, deltaV ₁ For the influence quantity, k, of the wind speed and the wind direction on the navigational speed in the preset first time period _w Is the first influence coefficient of wind speed and wind direction on navigational speed, deltaV ₂ The influence quantity k of the ocean current on the navigational speed in the preset first time period _f For the second influence coefficient of the ocean current on the navigational speed, t ₁ For the first moment, t ₂ And the second time is the second time, and the time period between the first time and the second time is the preset first time period.

By adopting the technical scheme, the formula not only considers the internal power performance of the ship, but also considers external environmental factors such as wind power and ocean current, so that the speed prediction is closer to the actual sailing condition. However, no other factors are introduced in the formula, because for the computational scenario of the present application, other factors affecting the speed of the ship are fixed factors, such as the ship load, which remain substantially unchanged during a single voyage, and are ignored in predicting the speed of the ship to reduce the computational effort. By introducing the influence coefficients of wind speed and ocean current, personalized adjustment can be performed aiming at different ships and navigation environments, and the prediction accuracy is improved.

Optionally, when there is a first predicted speed that is the same as the first actual speed among the plurality of first predicted speeds, determining to calculate a target weight value corresponding to each of the impact weights when the first predicted speed is the same as the first actual speed, including:

selecting a plurality of different influence coefficient groups included by the influence weights, wherein the influence coefficient groups comprise a first influence coefficient and a second influence coefficient, one first influence coefficient corresponds to one second influence coefficient, and the values of the first influence coefficient and the second influence coefficient are the initial weight values;

calculating a plurality of first predicted speeds through a first influence coefficient and a second influence coefficient corresponding to each influence coefficient group;

determining a predicted difference value between each of the first predicted speeds and the first actual speed;

and if the prediction difference value is smaller than the preset threshold value, setting the value of the first influence coefficient and the value of the second influence coefficient contained in the corresponding influence coefficient group as the target weight value.

By adopting the technical scheme, the navigational speed prediction model is optimized by selecting and adjusting different influence coefficients, so that the predicted navigational speed is closer to the actual navigational speed, and the prediction accuracy is improved. Specifically, in the scheme, a series of different combinations of influence coefficients (a first influence coefficient and a second influence coefficient) are selected, a corresponding first predicted navigational speed is calculated, and the first predicted navigational speed is compared with an actual navigational speed to determine a predicted difference value. When the prediction difference value obtained by a certain coefficient combination is smaller than a preset threshold value, the group of influence coefficients can be considered to effectively predict the navigational speed, and therefore the numerical value of the group of coefficients is set as an influence weight value.

Optionally, the influence quantity of the wind speed and the wind direction on the navigational speed is specifically calculated by the following formula:

；

wherein DeltaV ₁ The influence quantity of the wind speed and the wind direction on the navigational speed in the preset first time period is t ₁ For the first time, t ₂ For the second time, ρ _w Is of air density, C _w A is the wind resistance coefficient _w For the windward area of the target ship, V _p For the theoretical navigational speed, V of the power output of the ship in the preset first time period _w For the wind speed value, θ, within the preset first period _w Is the wind direction, theta _s M is the heading of the target ship in the preset first time periodThe total weight of the target vessel.

Optionally, the influence quantity of the ocean current on the navigational speed is calculated specifically by the following formula:

；

wherein t is ₁ For the first time, t ₂ For the second time, deltaV ₂ The influence quantity of the ocean current on the navigational speed in the preset first time period is V _p For the theoretical navigational speed, ρ of the power output of the ship in the preset first time period _c For ocean current density f _c Is water resistance coefficient, A _c For the water facing area of the target ship, V _c And the ocean current speed in the preset first time period is set, and T is the displacement of the target ship.

Alternatively, the theoretical navigational speed of the power take-off of the ship is specifically calculated by the following formula:

；

Wherein t is ₁ For the first time, t ₂ For the second time, deltaV _p For the theoretical navigational speed, P, of the power output of the ship in the preset first time period _o And T is the displacement of the target ship for the propulsion power of the target ship in the preset first time period.

Optionally, when the satellite positioning data cannot be acquired, determining, based on the acquired speed impact data and the target weight value, the positioning of the target ship through the calculated second predicted speed of the target ship specifically includes:

if it is determined that the satellite positioning data is not acquired within a preset time period from a third moment, calculating a second predicted navigational speed of the target ship within a preset second time period through each navigational speed influence data and the influence weight, wherein a time period between the third moment and a fourth moment is the preset second time period;

calculating the predicted sailing distance of the target ship according to the second predicted sailing speed and the duration of the preset second time period;

judging whether the predicted sailing distance is smaller than or equal to a preset distance threshold value, and if the predicted sailing distance is smaller than or equal to the preset distance threshold value, calculating the position of the target ship at a fourth moment according to the position of the target ship at the third moment and the predicted sailing distance.

By adopting the technical scheme, the predicted navigational speed of the ship under the condition of no satellite data is calculated by evaluating a plurality of factors influencing navigational speed and corresponding weight values. The process includes calculating a second predicted voyage based on the influencing factors and the weights for a predetermined period of time, and then estimating a predicted voyage distance of the vessel using the voyage distance. If the predicted distance is within a reasonable threshold, this information can be used to infer the position of the vessel at a later time. In the event that satellite signals are lost or unavailable, this approach provides an alternative positioning means to help maintain continuity and accuracy of vessel navigation.

In a second aspect of the present application, a marine positioning device is provided, including an acquisition module, a processing module, and a determination module, wherein:

the acquisition module is used for acquiring satellite positioning data aiming at a target ship;

the processing module is used for calculating a first actual navigational speed of the target ship according to the satellite positioning data, wherein the first actual navigational speed is the actual navigational speed of the target ship;

the acquisition module is used for acquiring the navigational speed influence data of the target ship, wherein the navigational speed influence data is data of various factors influencing the navigational speed of the target ship;

The processing module is used for calculating a plurality of first predicted speeds of the target ship in a preset first time period through each speed influence data and an initial weight value of a corresponding influence weight;

the judging module is used for determining and calculating target weight values corresponding to the influence weights when the first predicted speed which is the same as the first actual speed exists in the plurality of first predicted speeds;

and the processing module is used for determining the positioning of the target ship through the calculated second predicted navigational speed of the target ship based on the navigational speed influence data and the target weight value when the satellite positioning data cannot be acquired.

In a third aspect the present application provides an electronic device comprising a processor, a memory for storing instructions, a user interface and a network interface, both for communicating with other devices, the processor being for executing the instructions stored in the memory to cause the electronic device to perform a method as claimed in any one of the preceding claims.

In a fourth aspect of the present application, there is provided a computer readable storage medium storing instructions that, when executed, perform a method as claimed in any one of the preceding claims.

In summary, one or more technical solutions provided in the embodiments of the present application at least have the following technical effects or advantages:

the method and the device can be used for performing offshore positioning when the ship cannot receive Global Navigation Satellite System (GNSS) signals, because the method and the device do not depend on satellite positioning data only, but are combined with various navigational speed influencing factors to calculate the predicted navigational speed of the ship.

Specifically, this scheme first calculates the actual speed of the ship when it is able to receive satellite positioning data, and collects data of various factors affecting the speed. Then, a predicted voyage is calculated from the data and the corresponding impact weights. In the process, the weight value of each factor affecting the navigational speed is determined, the predicted navigational speed is matched with the actual navigational speed, the accurate weight value affecting the weight is determined, the weight of each factor affecting the navigational speed is equivalent to the weight of each factor affecting the navigational speed, and the follow-up more accurate predicted navigational speed is facilitated. When the ship cannot receive the satellite signals, a second predicted navigational speed is calculated through the weight value determined before and the acquired navigational speed influence data. Since these influencing factors and weight values have been calibrated according to the actual speed, the second predicted speed may more accurately reflect the motion state of the vessel. Based on this predicted voyage speed and the known last satellite positioning point, the current position of the vessel in the absence of satellite signals can be estimated.

In summary, by integrating a number of factors affecting the speed of the ship and utilizing a previously calibrated data model, the position of the ship can be effectively predicted even in the event that GNSS signals cannot be received.

Drawings

FIG. 1 is a schematic flow chart of a marine positioning method disclosed in an embodiment of the present application;

fig. 2 is a schematic view of an application scenario of a positioning method for a ship according to an embodiment of the present application;

FIG. 3 is a block schematic diagram of a marine positioning device according to an embodiment of the disclosure;

fig. 4 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Reference numerals illustrate: 200. a server; 201. a satellite positioning module; 202. a wind direction measurement module; 203. a wind speed measurement module; 204. the ocean current measurement module; 301. an acquisition module; 302. a processing module; 303. a judging module; 401. a processor; 402. a communication bus; 403. a user interface; 404. a network interface; 405. a memory.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present specification, the technical solutions in the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is obvious that the described embodiments are only some embodiments of the present application, but not all embodiments.

In the description of embodiments of the present application, words such as "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described herein as "such as" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "or" for example "is intended to present related concepts in a concrete fashion.

In the description of the embodiments of the present application, the term "plurality" means two or more. For example, a plurality of systems means two or more systems, and a plurality of screen terminals means two or more screen terminals. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating an indicated technical feature. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

At present, the positioning of a ship during offshore navigation mainly depends on a Global Navigation Satellite System (GNSS), but due to the natural vulnerability of signals of the global navigation satellite system and the fact that the signals cannot completely cover all the surfaces of the earth, the ship cannot be positioned through the global navigation satellite system at a certain time during navigation, so that the navigation accuracy is affected. There is a need for a method that enables offshore positioning in a short time when the vessel is unable to receive signals from the global navigation satellite system.

The embodiment discloses a marine positioning method, referring to fig. 1, comprising the following steps:

s110, satellite positioning data for a target ship are acquired.

The marine positioning method disclosed in the embodiments of the present application is applied to the server 200, and the server 200 includes, but is not limited to, electronic devices such as a mobile phone, a tablet computer, a wearable device, a PC (Personal Computer, a personal computer), and the like, and may also be a background server 200 running a marine positioning method. The server 200 may be implemented as a single server 200 or as a cluster of servers 200 comprising a plurality of servers 200.

A server 200 is provided in the target vessel, and with reference to fig. 2, a satellite positioning module 201 is connected, the satellite positioning module 201 being for determining and tracking the exact position of the vessel at sea using satellite signals. This module is typically based on the Global Positioning System (GPS) or other satellite navigation system, such as glonass, galileo or beidou, to provide key information for the positioning of the vessel, including its longitude, latitude, heading and speed, etc.

The server 200 and the satellite positioning module 201 are preferably connected by wire, and can also perform wireless communication through bluetooth to realize data transmission. When signals of the global navigation satellite system can be received, the satellite positioning module 201 receives signals from a plurality of satellites, which include the positions of the satellites and the time at which the signals were transmitted. These data are then transmitted to the server 200, and the server 200 calculates the transmission time of each satellite signal, thereby determining the distance between the target vessel and each satellite. By calculating the distance between the target ship and at least three satellites, the server 200 can accurately calculate the three-dimensional position data of the target ship at sea, i.e. obtain the satellite positioning data of the target ship. Once the position data is obtained, the server 200 may monitor the position and motion of the vessel in real time.

S120, calculating a first actual navigational speed of the target ship according to the satellite positioning data.

The server 200 pre-processes the collected data to filter out possible errors or outliers, including removing obvious erroneous readings or applying a smoothing algorithm to reduce random fluctuations. The server 200 then uses two or more consecutive location data points (each point including a longitude, latitude, and time stamp) to calculate the speed of the vessel. Normally, the distance between two points on the earth should be calculated according to the longitude and latitude between the two points, and this is achieved by a spherical trigonometry formula, such as the formula Ha Fuxin (Haversine formula). However, the ship positioning method disclosed by the application is mainly used for performing ship positioning calculation at a short distance, namely, when the distance is not more than 100 km, the influence on the curvature of the earth is very small and can be ignored under the condition that the distance is tens km or less. It can be seen directly that the time interval between two data points on a plane is determined, and then the first actual speed of the target vessel is calculated using the distance divided by time, the speed unit typically being knots (sea/hour). The first actual navigational speed is calculated based on satellite positioning data, and the actual navigational speed of the target ship is under the influence of ocean currents, ocean waves, sea winds and other factors.

S130, acquiring navigational speed influence data of the target ship

Different profile designs, vessel loading, hull cleanliness, maintenance and other physical conditions may affect the voyage of the target vessel, but these factors remain substantially unchanged for vessel positioning calculations within a short distance in the present application. Namely, the target ship runs for 100 kilometers, the ship body cleanliness and the like of the target ship cannot change too much, so that the influence on the speed in the distance basically remains unchanged, and the influence can be ignored in subsequent calculation.

On the contrary, relative to the factors which keep the influence on the navigational speed unchanged, the wind speed, the wind direction, the ocean current and other environmental factors can change in the running process of the target ship, so that the navigational speed of the ship is influenced to different degrees. For example, when wind blows from behind the vessel, it provides additional thrust to assist the vessel in its forward motion, in which case the actual speed of the vessel when power is unchanged will be higher than in the windless state. If the same vessel encounters headwind at a speed of 15 knots, it may drop to 14 knots or less with the power remaining unchanged, as it needs to overcome the drag of the wind.

In one possible implementation manner, acquiring the navigational speed influence data of the target ship specifically includes: acquiring wind direction data recorded by the wind direction measurement module 202; determining a relative direction of the wind direction with respect to the direction of travel based on the wind direction data and the direction of travel of the target vessel; acquiring wind speed data recorded by a wind speed measurement module 203; acquiring flow velocity data recorded by the ocean current measurement module 204; the data of the relative direction, the wind speed data and the flow speed data are determined as the navigational speed influence data.

Specifically, referring to fig. 2, the server 200 is also connected with a wind direction measurement module 202, a wind speed measurement module 203 and an ocean current measurement module 204, and the server 200 is preferably connected with the wind direction measurement module 202, the wind speed measurement module 203 and the ocean current measurement module 204 by wires, and can also perform wireless communication through bluetooth to realize data transmission.

The anemometer module 203 comprises a cup anemometer consisting of three or four hemispherical cups, fixed at the end on the horizontal axis, and an electronic sensor. When the wind blows over the cup, it rotates the entire device. The higher the wind speed, the faster the rotational speed, and the rotational speed of the cup is proportional to the wind speed. The wind speed is typically calculated by measuring the number of revolutions over a period of time, and the rotational speed is recorded by an electronic sensor and converted into a wind speed value, which is finally transmitted to the server 200.

The wind speed measurement module 203 comprises a wind vane, typically consisting of a stationary shaft, and a rotating part, typically in the shape of an arrow at one end and a light at the other end, typically in the shape of a plane or tail. The heavy end points to the source of wind and the light end points to the wind direction. When the wind blows, the light end of the wind vane is forced downward by the wind pressure, so that the heavy end (arrow) is directed to the source of the wind, i.e., the wind direction. The electronic sensor records the wind direction by being connected thereto and transmits the wind direction data to the server 200. The server 200 determines a relative direction of the wind direction with respect to the sailing direction according to the sailing direction of the target ship measured by the electronic compass.

The ocean current measurement module 204 is preferably a Doppler velocimeter (Doppler Current Profilers) that uses the Doppler effect to measure the velocity of the water flow. The Doppler flowmeter transmits sound waves and receives reflected sound wave signals, the speed of water flow can cause the frequency of the reflected sound waves to change, and the speed and direction of water flow can be calculated through the change.

And S140, calculating a plurality of first predicted speeds of the target ship in a preset first time period through each speed influence data and the initial weight value of the corresponding influence weight.

According to the actual situation, during the sailing of the ship, the wind speed, the wind direction and the ocean current flow velocity may all change, and the change has no specific rule. And thus the propulsion power of the target vessel may vary according to the change in the navigational speed influence data. And calculating a plurality of first predicted speeds of the target ship in a preset first time period by using each speed influence data and the initial weight value of the corresponding influence weight, wherein the speed influence data comprises wind speed data, wind speed data and ocean current data, and the influence weights are the influence weights of wind speed and wind direction on the speed and the influence weights of ocean current on the speed. Specifically, the method is calculated by the following formula:

；

wherein V is _r For a first predicted speed within a preset first period of time, deltaV _p For presetting the theoretical navigational speed of the power output of the ship in the first time period, delta V ₁ For presetting the influence quantity k of wind speed and wind direction on navigational speed in a first time period _w Is the first influence coefficient of wind speed and wind direction on navigational speed, deltaV ₂ For presetting the influence quantity k of ocean current on the navigational speed in the first time period _f Is the second influence coefficient of ocean current on the navigational speed, t ₁ For the first moment, t ₂ The second time is a preset first time period.

According to the formula, the influence quantity of wind speed and wind direction on the navigational speed in the first time period and the influence quantity of ocean current on the navigational speed in the first time period are preset, and the influence quantity is navigational speed influence data. The first influence coefficient and the second influence coefficient are influence weights, and the value of the first influence coefficient and the value of the second influence coefficient are initial weight values.

The formula not only considers the inherent dynamic performance of the ship, but also considers external environmental factors such as wind power and ocean currents, so that the navigational speed prediction is closer to the actual navigational situation. However, no other factors are introduced in the formula, because for the computational scenario of the present application, other factors affecting the speed of the ship are fixed factors, such as the ship load, which remain substantially unchanged during a single voyage, and are ignored in predicting the speed of the ship to reduce the computational effort. By introducing the influence coefficients of wind speed and ocean current, personalized adjustment can be performed aiming at different ships and navigation environments, and the prediction accuracy is improved.

The influence quantity of wind speed and wind direction on navigational speed is calculated by the following formula:

；

wherein DeltaV ₁ For presetting the influence quantity of wind speed and wind direction on navigational speed in a first time period, t ₁ For the first moment, t ₂ For the second time ρ _w Is of air density, C _w A is the wind resistance coefficient _w Is the windward area of the target ship, V _p For presetting the theoretical navigational speed of the power output of the ship in the first time period, V _w For presetting the wind speed value theta in the first time period _w Is the wind direction, theta _s And (3) presetting the heading of the target ship in a first time period, wherein M is the total weight of the target ship.

To calculate the amount of influence of wind on the target vessel speed, wind direction and their changes over time need to be considered. This problem needs to be solved by the principles of dynamics and hydrodynamics. First, several key parameters need to be specified: the windage coefficient is a dimensionless coefficient representing the amount of resistance of the fluid (in this case wind) to the target vessel. This coefficient depends on a number of factors, including the shape of the target vessel, surface roughness, etc. The wind resistance coefficient is thatThe present embodiment cannot be limited to specific values determined experimentally or by advanced computational methods (e.g., computational fluid dynamics). The air density is constant and is usually 1.225kg/m ³ And will not be described in any greater detail herein. The windward area is the surface area of the ship affected by wind, i.e. the sum of the areas of the surfaces blown by wind energy during running, and can be obtained by direct measurement. The theoretical navigational speed of the power take-off of the vessel will be described in more detail below.

To calculate the overall effect of wind on the speed of the vessel, this force needs to be translated into a change in speed. This can be achieved by newton's second law, where the acceleration caused by wind. The amount of change in speed over a particular time is then calculated by integration. Expressed at time t ₁ To t ₂ The speed of the ship changes due to wind power. It should be noted that this formula assumes the wind speed V over the considered period of time _w Wind direction theta _w Area A of windward ship _w Coefficient of resistance C _w And air density ρ _w Is a constant. If these parameters change over time, they need to be taken as a function of time and a corresponding integration calculation made.

For the influence quantity of ocean currents on the navigational speed, the method is specifically calculated by the following formula:

；

wherein t is ₁ For the first moment, t ₂ For the second moment DeltaV ₂ For presetting the influence quantity of ocean current on navigational speed in a first time period, V _p For presetting the theoretical navigational speed, ρ of the power output of the ship in the first time period _c For ocean current density f _c Is water resistance coefficient, A _c Is the water facing area of the target ship, V _c And (3) presetting the ocean current speed in a first time period, wherein T is the displacement of the target ship.

The calculation principle of the formula can refer to the influence of wind speed on navigational speed, and only in a short distance, the flow direction of ocean current can be basically regarded as fixed, the change of wind direction is avoided, the change of wind direction is possible, and further the integration of wind direction is also required. And according to the relative direction of the wind direction relative to the navigation direction, namely the difference between the wind direction and the navigation direction, a cosine value is obtained and is used for determining the influence of the relative direction of the wind on the navigation speed. The water-facing area of a ship, i.e. the surface area of the hull in contact with water. The larger this area, the greater the resistance the vessel is subjected to.

For the theoretical navigational speed of the power output of the ship, the theoretical navigational speed is calculated by the following formula:

；

wherein t is ₁ For the first moment, t ₂ For the second moment DeltaV _p For presetting the theoretical navigational speed, P, of the power output of the ship in the first time period _o And (3) presetting the propulsion power of the target ship in a first time period, wherein T is the displacement of the target ship.

It has been mentioned above that the difference between the first moment and the second moment is a preset first time period, the target ship propulsion power, representing the output power of the ship engine or propulsion system at that moment. And the displacement of the target vessel, i.e. the weight of the vessel to displace water. The displacement is an important index for measuring the size and weight of the ship, and directly affects the navigational speed of the ship. This expression is central to calculating the change in voyage. It estimates the change in speed of the ship based on the ratio of power to displacement. A cube root is used here, indicating that the relationship between power and speed is not linear. Generally, to increase the speed of the voyage significantly, the power needs to be increased by a larger proportion.

And S150, determining and calculating target weight values corresponding to the respective influence weights when the first predicted speed which is the same as the first actual speed exists in the plurality of first predicted speeds.

In the calculation formula of the first predicted speed, the input part can calculate other parameters except the first influence coefficient of the wind speed and the wind direction on the speed and the second influence coefficient of the ocean current on the speed. The first influence coefficient and the second influence coefficient are used as influence weights corresponding to the navigational speed influence data, and the numerical value of the first influence coefficient and the second influence coefficient plays a vital role in calculating the accuracy of the first predicted navigational speed. And as a variable, the value may be different for different situations, for example, when the weight of the ship is different or the design of the external shape is different, the influence of the wind speed, the wind direction or the ocean current on the ship speed may be different.

For the calculation formula of the first predicted voyage speed, different influence coefficient sets are selected, and each influence coefficient set comprises a first influence coefficient and a second influence coefficient. And the values of the first influence coefficient and the values of the second influence coefficient cannot be the same at the same time in the different sets of influence coefficients. For example, for a first set of influence coefficients, the first influence coefficient is a and the second influence coefficient is b, then in the second set of influence coefficients, the second influence coefficient cannot be b while the first influence coefficient is a. But the second influence coefficient may be c while the first influence coefficient is a, or the first influence coefficient may be a while the second influence coefficient is b.

And then sequentially inputting each group of influence coefficient groups into the calculation formula of the first predicted navigational speed, and outputting the calculation result of the first predicted navigational speed. After the first predicted speed is calculated by the calculation formula of the first predicted speed, a plurality of first predicted speeds are obtained. After calculating the first actual speeds of the target vessels from the satellite positioning data in steps S110 to S120, the server 200 calculates the predicted difference values of the respective first predicted speeds and the first actual speeds. And then judging the magnitude relation between the predicted difference value and a preset threshold value, wherein the magnitude of the preset threshold value influences the accuracy of the first predicted aviation increase influence coefficient. The accuracy of the selection of the influence coefficient is low due to the fact that the preset threshold value is too large, and the accuracy of the predicted navigational speed is reduced after the predicted navigational speed is calculated again. The preset threshold is too small, which results in larger calculation amount, and needs to be continuously tried to calculate, resulting in lower efficiency, so that the preset threshold needs to be adjusted according to actual conditions, and the embodiment cannot make specific limitation.

After a first predicted navigational speed is calculated through a certain influence coefficient group comprising a first influence coefficient and a second influence coefficient, and when the predicted difference value between the first predicted navigational speed and the first actual navigational speed is smaller than a preset threshold value, setting a numerical value corresponding to the first influence coefficient and a numerical value of the second influence coefficient as a weight value corresponding to an influence weight, and introducing a calculation formula of the first predicted navigational speed to predict navigational speed under the condition that no satellite signal exists subsequently, so as to calculate the positioning of a target ship.

In one possible implementation manner, the initial weight value of each speed influencing data and the corresponding influencing weight is a null value when the first predicted speed of the target ship in the preset first period is calculated according to the calculation formula of the first predicted speed. I.e. the values of the first influence coefficient and the second influence coefficient are both zero. It is therefore necessary to extrapolate specific values of the first and second influence coefficients through the formula, and it is necessary to calculate through multiple sets of data sets. Each set of data includes a first predicted speed that is the same as the first actual speed, and theoretical speed, wind speed, and wind direction of the power output of the vessel of the target vessel during the period of time by acquiring satellite positioning data and calculating the first actual speed, and ocean current to speed. And then, reversely pushing through a plurality of groups of data sets to obtain a group of target weight values for subsequent voyage speed prediction.

And the navigational speed prediction model is optimized by selecting and adjusting different influence coefficients, so that the predicted navigational speed is closer to the actual navigational speed, and the prediction accuracy is improved. Specifically, in the scheme, a series of different combinations of influence coefficients (a first influence coefficient and a second influence coefficient) are selected, a corresponding first predicted navigational speed is calculated, and the first predicted navigational speed is compared with an actual navigational speed to determine a predicted difference value. When the prediction difference value obtained by a certain coefficient combination is smaller than a preset threshold value, the group of influence coefficients can be considered to effectively predict the navigational speed, and therefore the numerical value of the group of coefficients is set as an influence weight value.

And S160, when the satellite positioning data cannot be acquired, determining the positioning of the target ship through the calculated second predicted navigational speed of the target ship based on the acquired navigational speed influence data and the target weight value.

First, a second predicted airspeed is calculated based on the following formula:

；

wherein V is _r ' is a second predicted speed for a preset second period of time, deltaV _p ' is the theoretical navigational speed of the power output of the ship in the preset second time period, and DeltaV ₁ ' is the influence quantity of wind speed and wind direction on navigational speed in a preset second time period, k _w Is the first influence coefficient of wind speed and wind direction on navigational speed, deltaV ₂ ' is the influence quantity k of ocean current on the navigational speed in a preset second time period _f Is the second influence coefficient of ocean current on the navigational speed, t ₃ At the third time t ₄ The time period between the third time and the fourth time is a preset second time period.

It should be noted that, at this time, the first influence coefficient and the second influence coefficient are the first influence coefficient and the second influence coefficient corresponding to the first predicted speed that is the same as the first actual speed in step S150, where the values of the first influence coefficient and the second influence coefficient are both the target weight values and are not the initial weight values.

The calculation process of the second predicted speed may refer to the calculation process of the first predicted speed, and both may be understood as predicting speeds in different time periods, so that a detailed description of the calculation process of the second predicted speed is omitted herein.

As can be seen from the calculation formula of the second predicted speed, for different times, when any one or more of the wind speed, wind direction, ocean current speed or power output changes, the speed will change. Therefore, it can be understood that the target ship does the variable acceleration curve motion within the preset second time period, and integration is required according to the second predicted navigational speed values of different times, so as to calculate the predicted navigational distance of the target ship according to the duration of the preset second time period.

In step S120, it is mentioned that the marine positioning method disclosed in the embodiment of the present application is mainly suitable for performing short-distance ship positioning calculation, and when the calculated predicted sailing distance is too long, the accuracy of the result calculated by the scheme of the present application is lower, so that the reference meaning of the predicted positioning is smaller. Therefore, after calculating the predicted travel distance of the target ship, the server 200 determines the magnitude relation between the predicted travel distance and the preset distance threshold. The value of the preset distance threshold is preferably 100 km, because the influence of the curvature of the earth is very small when the distance is not more than 100 km, and the curvature can be ignored, and the value can be other values, wherein the distance of 100 km is not the only choice of the preset distance threshold. If the predicted voyage distance is less than or equal to the preset distance threshold, the position of the target ship at the fourth time period can be calculated according to the position of the target ship at the third time period (the position at the moment can be obtained through satellite positioning data) and the calculated predicted voyage distance. It should be noted that the technology related to this calculation process is only a conventional technical means in the related art, and therefore will not be further described herein.

The predicted speed of the vessel without satellite data is calculated by evaluating a plurality of factors affecting the speed and corresponding weight values. The process includes calculating a second predicted voyage based on the influencing factors and the weights for a predetermined period of time, and then estimating a predicted voyage distance of the vessel using the voyage distance. If the predicted distance is within a reasonable threshold, this information can be used to infer the position of the vessel at a later time. In the event that satellite signals are lost or unavailable, this approach provides an alternative positioning means to help maintain continuity and accuracy of vessel navigation.

The embodiment also discloses a positioning device for a ship, referring to fig. 3, which includes an acquisition module 301, a processing module 302, and a judging module 303, wherein:

an acquisition module 301, configured to acquire satellite positioning data for a target ship.

The processing module 302 is configured to calculate a first actual navigation speed of the target ship according to the satellite positioning data, where the first actual navigation speed is an actual navigation speed of the target ship.

The acquiring module 301 is configured to acquire speed affecting data of the target ship, where the speed affecting data is data of multiple factors affecting the speed of the target ship.

The processing module 302 is configured to calculate, according to each of the voyage impact data and the initial weight value of the corresponding impact weight, a plurality of first predicted voyages of the target ship within a preset first time period.

A judging module 303, configured to determine, when a first predicted speed that is the same as the first actual speed exists among the plurality of first predicted speeds, a target weight value corresponding to each influence weight when the first predicted speed that is the same as the first actual speed is calculated;

the processing module 302 is configured to determine, when the satellite positioning data cannot be acquired, the positioning of the target ship based on the acquired navigational speed influence data and the target weight value through the calculated second predicted navigational speed of the target ship.

In a possible implementation manner, the processing module 302 is configured to calculate, according to each of the voyage impact data and the corresponding impact weight, a plurality of first predicted voyages of the target ship within the preset first period of time, specifically by the following formula:

；

In a possible implementation manner, the obtaining module 301 is configured to select different influence coefficient sets, where the influence coefficient sets include a first influence coefficient and a second influence coefficient, and one first influence coefficient corresponds to one second influence coefficient.

The processing module 302 is configured to calculate a first predicted navigational speed according to the influence coefficients corresponding to the respective influence coefficient groups.

A processing module 302 is configured to determine a predicted difference between the first predicted speed and the first actual speed.

The determining module 303 is configured to set a value of an influence coefficient included in the corresponding influence coefficient set as a weight value if the prediction difference is determined to be smaller than the preset threshold.

In one possible implementation, the processing module 302 is configured to calculate the influence amount of the wind speed and the wind direction on the navigational speed specifically by the following formula:

；

In one possible implementation, the processing module 302 is configured to calculate the influence amount of the ocean current on the navigational speed according to the following formula:

；

In one possible implementation, the processing module 302 calculates the theoretical navigational speed for the power take off of the vessel by specifically:

；

In a possible implementation manner, the processing module 302 is configured to calculate, if it is determined that the satellite positioning data is not acquired within the preset duration from the third time, a second predicted voyage speed of the target ship within a preset second time period according to the respective voyage speed influence data and the target weight value of the influence weight, where a time period between the third time and the fourth time period is the preset second time period.

The processing module 302 is configured to calculate a predicted sailing distance of the target ship according to the second predicted sailing speed and a duration of a preset second time period.

The judging module 303 is configured to judge whether the predicted sailing distance is less than or equal to a preset distance threshold, and if the predicted sailing distance is less than or equal to the preset distance threshold, calculate the position of the target ship at the fourth moment according to the position of the target ship at the third moment and the predicted sailing distance.

It should be noted that: in the device provided in the above embodiment, when implementing the functions thereof, only the division of the above functional modules is used as an example, in practical application, the above functional allocation may be implemented by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules, so as to implement all or part of the functions described above. In addition, the embodiments of the apparatus and the method provided in the foregoing embodiments belong to the same concept, and specific implementation processes of the embodiments of the method are detailed in the method embodiments, which are not repeated herein.

The embodiment also discloses an electronic device, referring to fig. 4, the electronic device may include: at least one processor 401, at least one communication bus 402, a user interface 403, a network interface 404, at least one memory 405.

Wherein communication bus 402 is used to enable connected communications between these components.

The user interface 403 may include a Display screen (Display) and a Camera (Camera), and the optional user interface 403 may further include a standard wired interface and a standard wireless interface.

The network interface 404 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface), among others.

Wherein the processor 401 may include one or more processing cores. The processor 401 connects the various parts within the entire server using various interfaces and lines, performs various functions of the server and processes data by executing or executing instructions, programs, code sets, or instruction sets stored in the memory 405, and invoking data stored in the memory 405. Alternatively, the processor 401 may be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field programmable gate array (Field-Programmable Gate Array, FPGA), programmable logic array (Programmable Logic Array, PLA). The processor 401 may integrate one or a combination of several of a central processor 401 (Central Processing Unit, CPU), an image processor 401 (Graphics Processing Unit, GPU), a modem, etc. The CPU mainly processes an operating system, a user interface, an application program and the like; the GPU is used for rendering and drawing the content required to be displayed by the display screen; the modem is used to handle wireless communications. It will be appreciated that the modem may not be integrated into the processor 401 and may be implemented by a single chip.

The Memory 405 may include a random access Memory 405 (Random Access Memory, RAM) or a Read-Only Memory 405 (Read-Only Memory). Optionally, the memory 405 includes a non-transitory computer readable medium (non-transitory computer-readable storage medium). Memory 405 may be used to store instructions, programs, code sets, or instruction sets. The memory 405 may include a stored program area and a stored data area, wherein the stored program area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playing function, an image playing function, etc.), instructions for implementing the above-described various method embodiments, etc.; the storage data area may store data or the like involved in the above respective method embodiments. The memory 405 may also optionally be at least one storage device located remotely from the aforementioned processor 401. As shown, an operating system, a network communication module, a user interface 403 module, and an application program of a ship positioning method may be included in the memory 405 as a computer storage medium.

In the electronic device shown in fig. 4, the user interface 403 is mainly used for providing an input interface for a user, and acquiring data input by the user; and the processor 401 may be used to invoke an application in the memory 405 storing a marine positioning method, which when executed by the one or more processors 401 causes the electronic device to perform the method as in one or more of the embodiments described above.

It should be noted that, for simplicity of description, the foregoing method embodiments are all expressed as a series of action combinations, but it should be understood by those skilled in the art that the present application is not limited by the order of actions described, as some steps may be performed in other order or simultaneously in accordance with the present application. Further, those skilled in the art will also appreciate that the embodiments described in the specification are all preferred embodiments, and that the acts and modules referred to are not necessarily required in the present application.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

In the several embodiments provided herein, it should be understood that the disclosed apparatus may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, such as a division of units, merely a division of logic functions, and there may be additional divisions in actual implementation, such as multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be through some service interface, device or unit indirect coupling or communication connection, electrical or otherwise.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable memory 405. Based on such understanding, the technical solution of the present application may be embodied in essence or a part contributing to the prior art or all or part of the technical solution in the form of a software product stored in a memory 405, including several instructions for causing a computer device (which may be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the methods of the embodiments of the present application. And the aforementioned memory 405 includes: various media capable of storing program codes, such as a U disk, a mobile hard disk, a magnetic disk or an optical disk.

The foregoing is merely exemplary embodiments of the present disclosure and is not intended to limit the scope of the present disclosure. That is, equivalent changes and modifications are contemplated by the teachings of this disclosure, which fall within the scope of the present disclosure. Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a scope and spirit of the disclosure being indicated by the claims.

Claims

1. A method of marine positioning, the method comprising:

acquiring satellite positioning data for a target ship;

2. The marine positioning method according to claim 1, wherein the calculating the plurality of first predicted speeds of the target ship within a preset first period of time is performed by using each of the speed influence data and an initial weight value of a corresponding influence weight, and specifically by using the following formula:

；

3. The method according to claim 2, wherein the determining the target weight value corresponding to each of the influence weights when the first predicted speed is the same as the first actual speed is calculated when the first predicted speed is the same as the first actual speed among the plurality of first predicted speeds includes:

4. The marine positioning method according to claim 2, wherein the influence of wind speed and wind direction on the navigational speed is calculated by the following formula:

；

wherein DeltaV ₁ The influence quantity of the wind speed and the wind direction on the navigational speed in the preset first time period is t ₁ For the first time, t ₂ For the second time, ρ _w Is of air density, C _w A is the wind resistance coefficient _w For the windward area of the target ship, V _p For the theoretical navigational speed, V of the power output of the ship in the preset first time period _w For the wind speed value, θ, within the preset first period _w Is the wind direction, theta _s And M is the total weight of the target ship and is the heading of the target ship in the preset first time period.

5. The marine positioning method according to claim 2, wherein the influence of the ocean current on the speed is calculated by the following formula:

；

6. The marine positioning method according to claim 2, wherein the theoretical navigational speed of the power take-off of the marine vessel is calculated in particular by the following formula:

；

7. The marine positioning method according to claim 1, wherein when the satellite positioning data cannot be acquired, determining the positioning of the target ship by the calculated second predicted navigational speed of the target ship based on the acquired navigational speed influence data and the weight value, specifically comprises:

If it is determined that the satellite positioning data is not acquired within a preset time period from a third moment, calculating a second predicted navigational speed of the target ship within a preset second time period through each navigational speed influence data and a target weight value of the influence weight, wherein a time period between the third moment and a fourth moment is the preset second time period;

8. The marine positioning device is characterized by comprising an acquisition module (301), a processing module (302) and a judging module (303), wherein:

the acquisition module (301) is used for acquiring satellite positioning data for a target ship;

the processing module (302) is configured to calculate a first actual navigational speed of the target ship according to the satellite positioning data, where the first actual navigational speed is an actual navigational speed of the target ship;

The acquisition module (301) is configured to acquire speed impact data of the target ship, where the speed impact data is data of multiple factors that impact the speed of the target ship;

the processing module (302) is configured to calculate, according to each of the voyage impact data and an initial weight value of a corresponding impact weight, a plurality of first predicted voyages of the target ship within a preset first period of time;

the judging module (303) is configured to determine, when a first predicted speed identical to the first actual speed exists among a plurality of first predicted speeds, to calculate a target weight value corresponding to each of the influence weights when the first predicted speed identical to the first actual speed exists;

the processing module (302) is configured to determine, when the satellite positioning data cannot be acquired, a positioning of the target ship based on the acquired speed impact data and the target weight value, through the calculated second predicted speed of the target ship.

9. An electronic device comprising a processor (401), a memory (405), a user interface (403) and a network interface (404), the memory (405) being configured to store instructions, the user interface (403) and the network interface (404) being configured to communicate with other devices, the processor (401) being configured to execute the instructions stored in the memory (405) to cause the electronic device to perform the method of any of claims 1-7.

10. A computer readable storage medium storing instructions which, when executed, perform the method of any one of claims 1-7.