How to display other ships using international VHF communications

Abstract

To contribute to safe marine navigation by solving the conventional problem that a communication partner cannot know where a present ship is being navigated by recognizing in voice a ship name included in the communication partner when performing international VHF communications between ships and notifying a user of a partner ship displayed on a display device such as ECDIS or displaying an alarm in a case where the communication partner is not the ship being displayed on the display device.SOLUTION: A device for implementing safe navigation utilizing inter-ship communications based on international VHF communications comprises: an electronic marine chart information display unit which displays ship position information included in a communication with an AIS mounted ship; a learning type voice recognition unit which recognizes a voice sequence of voice data when performing voice communications with the AIS mounted ship; a ship name extraction unit which extracts a partner ship name and a partner identification number from the voice sequence recognized by the learning type voice recognition unit; and a positional information superposing unit which superposes an extraction result of the ship name extraction unit on the electronic marine chart information display unit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] While it is possible to determine where other ships are located on the ocean by looking at the display on an ECDIS (Electronic Chart Display and Information System), it is difficult to determine which ship on the ECDIS is communicating with via international VHF communications, etc. The present invention aims to solve this problem in order to contribute to safe navigation. [Background technology]

[0002] In recent years, autonomous driving in automobiles has made great progress, and its practical application is imminent. Similarly, research into autonomous navigation for ships has been active, and it is said that this too will soon be put into practical use. However, while there are buoys that indicate routes in limited areas such as congested waters, safe navigation on the ocean largely relies on individual communication between ships to confirm their coordinates and direction of travel.

[0003] For safety reasons, AIS (Automatic Identification System) is widely used on the ocean, and the coordinates of other ships that become clear by receiving the AIS signal can be displayed on ECDIS, allowing ships to understand the situation around their own ship. The information displayed includes heading, heading, and destination, but since AIS information alone does not tell the timing of course changes, safety is often confirmed by individual voice communication just to be sure.

[0004] Furthermore, the low adoption rate of AIS among small fishing boats, for which there is no requirement to install AIS, is also a problem. Many owners of these small fishing boats are hesitant to notify fishing cooperatives of their fishing situation, and the adoption rate is very low. To improve safety in these cases, there is active research into methods for determining the location of non-AIS-equipped vessels. One method, for example, is to use multiple directional antennas to locate the transmission location of communication signals from non-AIS-equipped vessels.

[0005] In recent years, there has also been a report of a method that takes advantage of the fact that there is a certain relationship between the amount of noise components in international VHF communications and the distance between communications, and estimates the distance between parties in international VHF communications by analyzing the noise components.

[0006] This invention assumes that surrounding ships are equipped with AIS, and relates to a means of enhancing safety by combining ship information obtained from voice calls with position information obtained from the AIS. In addition, when a ship without AIS is discovered, it is possible to notify the crew by issuing a warning or other means. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2017-163300 Summary of the Invention [Problem to be solved by the invention]

[0008] When multiple ships are sailing on the ocean aiming for safe navigation, the first step to ensure safety is to know the positions of other ships displayed on the ECDIS. However, just because another ship is sailing nearby does not mean that they will always avoid it, and in congested waters, the reality is that in many cases ships will approach each other after mutual understanding through individual communications, etc. In such cases, it is difficult to judge safety simply based on information obtained from the screen.

[0009] Sailing with mutual understanding as mentioned above means communicating at any time via international VHF communication about the direction of navigation, the status of each other's position, etc. Therefore, if the information about other ships plotted on the ECDIS could also indicate whether they are communicating with international VHF communication partners, the information could be used more effectively.

[0010] To achieve this, it is conceivable to use voice recognition on the voice data of international VHF communications and link this to AIS information using the location and ship names contained in the voice sequence, but currently the information contained in the voice sequence and the AIS information are treated separately.

[0011] Thus, the present invention aims to make it possible to know whether an approaching ship displayed on ECDIS is the party with whom communication is being conducted by performing voice recognition on the voice signals contained in the communication, identifying the ship name contained in the voice and linking it to AIS information to add information to ECDIS, and to prevent a decrease in voice recognition rate even in high-noise international VHF communications at sea. [Means for solving the problem]

[0012] This device realizes safe navigation using ship-to-ship communications via international VHF radio. The ship name information obtained by recognizing the voice information in the international VHF communication by the learning voice recognition unit is designated as ship name information 1, The ship name information included in the AIS information transmitted by the AIS devices of multiple ships received by the ship is defined as a ship name information group, When the result of searching the ship name information group for the ship name information that is equal to or smaller than a predetermined threshold and has the smallest error with ship name information 1 is set as ship name information 2, The system is characterized by having a ship name extraction unit that links the ship name information 2 with the ship name information 1. The method of displaying other ships will be based on international VHF communications.

[0013] an electronic chart information display unit that displays ship information obtained from AIS information; an information superimposing unit that superimposes the linking result of the ship name extraction unit on the electronic chart information display unit; A method for displaying other ships using international VHF communications, characterized by the following:

[0014] The learning-type speech recognition unit a learning data setting unit that sets the ship name voice signal in the international VHF communication as learning data; a teacher data setting unit that sets, as teacher data, a character string that has the smallest difference from the learning data from among the ship name information included in the AIS information; The method for displaying other ships using international VHF communications is characterized by comprising:

[0015] The learning-type speech recognition unit a voice storage unit for storing feature data of input voice; a stored voice determination unit that determines whether the currently input voice is feature data already stored in the voice storage unit; The method for displaying other ships using international VHF communications is characterized by comprising:

[0016] The learning-type speech recognition unit When the difference between the learning data set by the learning data setting unit and the teacher data set by the teacher data setting unit is equal to or greater than a predetermined threshold, The input vessel name voice signal is determined to be a vessel name not displayed on the electronic chart information display unit, The electronic chart information display unit is characterized by displaying a warning that the ship is not equipped with AIS. The method of displaying other ships will be based on international VHF communications. [Effects of the Invention]

[0017] According to claim 1 of the present invention, it is possible to use voice recognition to extract ship name information and identification numbers from the voice string of the other party in international VHF communication and link them to AIS information.

[0018] According to claim 2 of the present invention, it is possible to superimpose additional information about other vessels on a display device that displays nearby vessels, such as ECDIS. Note that superimposing additional information includes displaying information obtained by voice recognition or simply highlighting the information.

[0019] According to claim 3 of the present invention, even in adverse environments such as when weather conditions increase noise in international VHF communications, it is possible to perform highly accurate speech recognition of speech sequences by training a speech recognition device using AIS information as training data.

[0020] According to claim 4 of the present invention, by storing the voice characteristic information, when communicating again with a party with whom you have communicated once before, it is possible to superimpose the additional information of the other ship displayed on the display without performing voice recognition.

[0021] According to claim 5 of the present invention, if the other vessel communicating with the international VHF communication is not equipped with AIS, it is possible to detect this and issue a warning that the information may not be displayed on the electronic chart information display unit. [Brief explanation of the drawings]

[0022] [Figure 1] Examples of embodiments of the present invention [Figure 2] Overall processing flow [Figure 3] Speech recognition training data acquisition process flow [Figure 4] Audio data saving process flow [Figure 5] Processing flow for communication with non-AIS equipped ships DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. [Example]

[0024] Figure 1 shows information exchange using AIS (Automatic Identification System), where 101 is the other vessel, 103 is the vessel itself, 105 is equipment installed on land such as a maritime traffic center, and 107 is an ECDIS (Electronic Chart Display and Information System).

[0025] AIS is a device that allows ships navigating the ocean to exchange navigation information with each other, and from the perspective of collision prevention and life safety, it has been made mandatory for ships designated by the SOLAS Convention to be equipped with it. However, the current installation rate is still low for small fishing boats and other vessels. Therefore, when considering maritime safety, it is necessary not only to assume that AIS is installed, but also to consider a system that takes into account ships that do not have it installed.

[0026] As shown in Figure 1, AIS is composed of equipment installed on land and devices installed on ships. Individual data such as the ship's identification code, name, position, course, speed, and destination is automatically transmitted via VHF radio waves from the AIS device installed on ship 101, and is received by receivers on other ships 103 sailing nearby or by receiving equipment 105 installed at a maritime traffic center on land. The received information is visually communicated to passengers by, for example, ECDIS 107.

[0027] AIS-dedicated frequencies are allocated from the VHF maritime mobile service frequencies, and the communication range is basically equivalent to the line-of-sight range from the antenna, which is approximately 37 to 56 km.

[0028] Figure 2 shows the overall processing flow according to the present invention. The receiver 201 receives international VHF communications from other ships. In international VHF communications, it is common to first call the other ship on a contact setup channel, and then switch to a call channel to make the call. For convenience, the receiver 201 is shown after switching to the call channel.

[0029] When the receiver 201 receives an international VHF communication from the other ship, the voice signal is subjected to voice recognition by the voice recognition unit 203. The vocabulary recognized and extracted by the voice recognition unit 203 is the ship name. As will be described later, the extraction method can be a means of searching for the ship name contained in the AIS received information from a voice string, or by recognizing a phrase that indicates the ship name, such as "~maru" or "~go." In this way, the name of the other ship can be obtained from the communication voice by voice recognition.

[0030] Next, the display control unit 205 compares the acquired ship name with a list of ship names of surrounding ships acquired from AIS signals at any time, and searches for a ship that matches the ship name from the list. For ships with matching ship names, the display control unit 205 turns on a highlight flag for the ship.

[0031] The display unit 207 displays multiple ships sailing around the ship using the AIS device, and by emphasizing the color and brightness of ships with the highlight flag turned on, it is possible to visually identify ships with the highlight flag turned on.

[0032] In this way, the present invention makes it possible to visually identify the symbol of the other vessel communicating via international VHF communication among the symbols of other vessels scattered on the ECDIS, thereby enabling instant visual understanding of the relative position of the other vessel relative to the own vessel.

[0033] Figure 3 shows the process flow for improving the recognition rate of a speech recognition device. The process of changing various parameters of a speech recognition device to improve the recognition rate is also called training.

[0034] As mentioned above, AIS-equipped ships automatically transmit AIS information as needed, which includes the ship's identification code, name, position, course, destination, etc.

[0035] AIS information from surrounding ships is received by the AIS receiver 301, and the AIS information acquisition unit 303 identifies each of the AIS information. In this invention, ship name information is used from the AIS information. Meanwhile, crew members of both ships can exchange voice communications via international VHF radio. As shown in Figure 3, the international VHF receiver 305 receives signals from the other ship, and the voice recognition unit 307 recognizes the contents of the voice communication. In this invention, the name of the other ship is recognized.

[0036] In the present invention, the voice recognition unit 307 is trained by using the information obtained from the AIS information acquisition unit 303 as training data to adjust the voice recognition unit 307. Here, as an example, the case of learning ship names will be taken up.

[0037] The AIS information acquisition unit 303 acquires the character strings of the names of surrounding ships and creates a ship name database consisting of the number of surrounding ships. Meanwhile, the voice recognition unit 307 acquires the voice signals of other ships communicating via international VHF communication, recognizes these voice signals, and converts them into character strings. Since it is common for ships to state their names in voice signals at sea, the voices can be considered to contain the ship names.

[0038] Therefore, information can be added to ECDIS by performing voice recognition on the voice signal of international VHF communications and linking it to a ship name selected from a ship name database consisting of the AIS information, and various means of selection can be considered.

[0039] For example, each ship name database 309 is searched for the character string of the voice recognition result, and the ship name character string with the smallest difference is taken as the recognition result and linked to the corresponding AIS information.

[0040] As another method, since the ship name voice continues with phrases indicating that it is a ship name, such as "~maru" or "~go", the voice recognition unit 307 extracts these standard words from the voice string, then extracts the ship name, converts it into a string, and then compares the ship name string with the strings in the ship name database, and the ship name string with the smallest difference in the ship name database is used as the recognition result, and is linked to the corresponding AIS information.

[0041] Any of the methods for linking the voice recognition results with the AIS information may be used, but by linking them in this way, the voice recognition rate can be improved. In other words, the voice recognition results linked with the AIS information are used as training data, and the recognition rate is improved by learning from them so that the recognition result by the voice recognition unit 307 becomes the above-mentioned character string. In other words, as described above, neither the voice recognition result nor the ship name database 309 is a perfect match, and the result with the smallest error is used, but by repeating this process, the error will become smaller from the next process onwards.

[0042] The parameters used by the speech recognition unit 307 may be simply speech waveforms, but may also be any other parameters such as linear prediction coefficients (LPC coefficients), partial autocorrelation coefficients (PARCOR coefficients), speech features (cepstral coefficients), etc., and are not limited to these in the present invention.

[0043] Furthermore, when comparing the voice recognition results with the ship name database, it is possible to simply compare the waveforms or speech formant shapes corresponding to the characters. For example, it is possible to determine that there is little difference between "ta" and "cha" based on the plosive sounds and vowels that are close to sine waves obtained from the character information. However, the present invention does not limit the means for comparing such errors.

[0044] Furthermore, various methods can be considered as speech recognition means, such as a neural network method that modifies the coefficients of a group of filters using a method called backpropagation so that training data is output when training data is input to the group of filters, a deep learning method that has seen remarkable development in recent years, and a fuzzy inference method, but the present invention is not limited to these.

[0045] In this way, in the present invention, the voice recognition unit 307 performs voice recognition on the ship name to obtain the ship name string, and the ship name with the smallest error compared to the voice recognition result is extracted from the ship name database created by the AIS information acquisition unit 303, and this is used as training data to train the voice recognition unit 307.This makes it possible to maintain high voice recognition accuracy even when there is a lot of noise due to the effects of weather around the ship, making it more likely that misrecognition will occur.

[0046] 4 shows the flow for storing the above-mentioned parameters calculated for speech recognition by the speech recognition unit 403 using the international VHF speech signal received by the receiving unit 401. In other words, the speech waveform itself, linear prediction coefficients and partial autocorrelation coefficients generated during the speech recognition process, etc. are stored in the storage device 405. At the same time, the name of the vessel corresponding to the stored speech recognition result is also stored in association with the speech recognition result.

[0047] When the voice parameters of the other ship with which communication has been previously made are stored in the memory device 405 and a currently received voice signal is input to the voice recognition unit 403, the voice recognition unit first converts the voice signal into a parameter string for voice recognition as described above.

[0048] Next, the parameter sequence is compared with the parameter sequence stored in the storage device 405. If a parameter sequence with a difference amount equal to or less than the error threshold set as the initial value is found in the storage device 405, the vessel name of the speech recognition result stored in association with the found parameter sequence is taken as the speech recognition result.

[0049] With this processing, when communicating again with a ship with which communication has been previously conducted, if similar parameters exist in the memory device 405, it becomes possible to obtain the name of the other ship without performing subsequent recognition processing to calculate the voice parameters.

[0050] Here, if the difference amount is less than the error threshold, the present invention does not limit whether to perform a new speech recognition process to update the data stored in the storage device 405, or to output the speech recognition result without performing a speech recognition process.

[0051] Figure 5 shows a flow chart for explaining the case where the communication partner does not have an AIS device. As described above, when the voice recognition result is compared with the ship name database 513 consisting of AIS information obtained from the AIS receiver 511, if a matching ship name is not found within a predetermined error threshold, it can be determined that the communication partner does not have an AIS. The AIS presence / absence determination unit 501 stores the predetermined error threshold and calculates whether all errors between the voice recognition result and the ship name database 513 are equal to or greater than the error threshold.

[0052] In this case, the display control unit 507 transmits a character string indicating that the communication partner is not equipped with AIS to the display unit 509, and the character string is displayed on the display unit 509. Note that the character string can be displayed in any area on the display, by flashing a warning lamp, or by opening a separate window, and various other methods are conceivable, but the present invention is not limited to these. Furthermore, the displayed content is not limited to the fact that the communication partner is not equipped with AIS, and it is also possible to display a character string of the voice recognition result.

[0053] As described above, according to the present invention, when international VHF communications are conducted between ships, the name of the ship included in the communication partner can be recognized by voice, and the user can be informed of the other ship on a display device such as ECDIS.If the communication partner is a ship that does not have AIS and is not displayed on the display device, a warning can be displayed.This improves the problem that, in the past, it was not possible to instantly determine which of the surrounding ships displayed on the display device was the communication partner, and ultimately contributes to safe navigation. [Explanation of symbols]

[0054] 101...Communication partner vessel, 103...Own vessel, 105...Ground station, 107...ECDIS, 201...receiving unit, 203...voice recognition unit, 205...display control unit, 207...display unit, 301...AIS receiving unit, 303...AIS information acquisition unit, 305...International VHF receiver, 307...Voice recognition unit, 309... Ship Name Database, 401...receiving unit, 403...voice recognition unit, 405...Storage device, 501...AIS presence / absence determination unit, 503...International VHF receiving unit, 505...speech recognition unit, 507...display control unit, 509...display unit, 511...AIS receiving unit, 513...Ship name database

Claims

1. This device realizes safe navigation using ship-to-ship communications via international VHF radio. The ship name information obtained by recognizing the voice information in the international VHF communication by the learning voice recognition unit is designated as ship name information 1, The ship name information included in the AIS information transmitted by the AIS devices of multiple ships received by the ship is defined as a ship name information group, When the result of searching the ship name information group for the ship name information that is equal to or smaller than a predetermined threshold and has the smallest error with the ship name information 1 is set as ship name information 2, The system is characterized by having a ship name extraction unit that links the ship name information 2 with the ship name information 1. How to display other ships using international VHF communications

2. an electronic chart information display unit that displays ship information obtained from AIS information; an information superimposing unit that superimposes the linking result of the ship name extraction unit on the electronic chart information display unit; 2. The method for displaying other ships using international VHF communications according to claim 1, comprising:

3. The learning-type speech recognition unit a learning data setting unit that sets the ship name voice signal in the international VHF communication as learning data; a teacher data setting unit that sets, as teacher data, a character string that has the smallest difference from the learning data from among the ship name information included in the AIS information; 3. The method for displaying other ships using international VHF communications according to claim 1 or 2, comprising:

4. The learning-type speech recognition unit a voice storage unit for storing feature data of input voice; a stored voice determination unit that determines whether the currently input voice is feature data already stored in the voice storage unit; The method for displaying other ships using international VHF communications according to any one of claims 1 to 3, characterized in that:

5. A method for displaying other ships using the international VHF communication described in claim 2 and claim 3, The learning-type voice recognition unit determines that the input ship name voice signal is a ship name not displayed on the electronic chart information display unit when a difference between the learning data set by the learning data setting unit and the teacher data set by the teacher data setting unit is equal to or greater than a predetermined threshold, and warns the electronic chart information display unit that the ship is not equipped with AIS.

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