A method and system for transmitting ship attitude data

Abstract

This invention relates to the field of ship attitude monitoring, and discloses a method and system for ship attitude data transmission. The method includes: real-time acquisition of the ship's current navigation attitude data, and generating navigation status data based on the current navigation attitude data and the ship's current position information; compressing the navigation status data to obtain compressed navigation status data; performing anomaly prediction processing on the current navigation attitude data to obtain prediction results; determining a data transmission strategy based on the prediction results, and selecting to send either the compressed navigation status data or the current navigation attitude data to an external communication object based on the data transmission strategy. This improves bandwidth utilization by shortening the short message length, meeting the high-frequency sampling requirements of high-speed ships; and enhances security by prioritizing the use of a dedicated communication channel when the ship's roll exceeds a threshold, thus solving the technical problem of delayed anomaly response.

Description

Technical Field

[0001] This disclosure relates to the field of ship attitude monitoring, and in particular to a method and system for transmitting ship attitude data. Background Technology

[0002] Large ships require real-time monitoring of attitude data (bow, roll, pitch) to ensure navigational safety. Current technologies primarily rely on two transmission schemes: full-data transmission and sparse compression. Specifically: Full transmission scheme: Send complete attitude data (longitude, latitude, heading, roll, pitch) per second, requiring 35 bytes per transmission (e.g., NMEA-0183 format); Thinning compression schemes, such as the trajectory compression method of the Beihai Center of the Ministry of Transport, reduce the amount of data through differential coding, but do not solve the problem of coordinated compression of attitude data and position data, and lack an abnormal state triggering mechanism.

[0003] However, the current solution has the following main technical shortcomings in the relevant technologies: 1. Low bandwidth utilization: Attitude data redundancy; during normal navigation, attitude changes are slow, and full transmission wastes 70% of bandwidth. Actual measurements show that the ship's roll rate is ≤0.1° / s for 85% of the time periods. Abnormal response delay; when a fixed transmission interval is manually set (e.g., 60 seconds), the alarm delay exceeds 15 seconds when the roll exceeds 5°. Maritime accident reports show that nearly one-third of listing accidents are caused by alarm delays.

[0004] 2. Poor system compatibility: Attitude data and position data are transmitted separately, requiring additional timing alignment at the receiving end; Unadapted to ship motion characteristics: The difference in attitude change rate between low-speed ships (<10 knots) and high-speed ships (>20 knots) was not included in the compression strategy.

[0005] 3. Satellite bandwidth resource usage: Full transmission requires frequent use of short message resources (approximately 1440 messages per ship per day).

[0006] Therefore, a new method for transmitting ship attitude data is urgently needed to solve the technical problems mentioned above. Summary of the Invention

[0007] The purpose of this invention is to provide at least one method and system for transmitting ship attitude data. It aims to design a collaborative compression mechanism of attitude incremental coding (Δ coding) and position grid coding to compress a single set of attitude data from 35 bytes to ≤4 bytes (compression ratio >8:1); establish a trigger-based transmission strategy based on Kalman filter prediction to provide a real-time anomaly response when the ship's roll / pitch exceeds a threshold, ensuring an alarm delay of ≤3 seconds; and achieve adaptive compression of attitude data for ships with speeds of 10-40 knots through a speed-attitude coupled hierarchical quantization model.

[0008] To address the aforementioned technical problems, at least one embodiment of this application provides a method for transmitting ship attitude data, the method comprising: The ship's current navigation attitude data is collected in real time, and navigation status data is generated based on the current navigation attitude data and the ship's current position information; The navigation status data is compressed to obtain compressed navigation status data; Anomaly prediction processing is performed on the current navigation attitude data to obtain compressed navigation state data based on the prediction results; Based on the prediction results, a data transmission strategy is determined, and based on the data transmission strategy, the compressed navigation status data or the current navigation attitude data is selected to be sent to an external communication object.

[0009] At least one embodiment of this application also provides a ship attitude data transmission system, including: A communication device used to communicate with external communication objects; Data acquisition device, used to collect the ship's current navigation attitude data in real time; The controller is communicatively connected to both the data acquisition device and the communication device, and is configured to: generate navigation status data based on the ship's current position information and the current navigation attitude data; compress the navigation status data to obtain compressed navigation status data; perform anomaly prediction processing on the current navigation attitude data to obtain a prediction result; determine a data transmission strategy based on the prediction result, and select to send the compressed navigation status data or the current navigation attitude data to an external communication object based on the data transmission strategy.

[0010] At least one embodiment of this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described above.

[0011] At least one embodiment of this application also provides a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of the method described above.

[0012] At least one embodiment of this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described above.

[0013] The ship attitude data transmission method and system provided in this application have improved bandwidth utilization compared with the prior art: the short message length is shortened, and the amount of attitude data that can be transmitted is increased by 8 times, meeting the high-frequency sampling requirements of high-speed ships; and the safety is enhanced: when the ship's roll exceeds the threshold, the alarm information uses a dedicated communication channel first, thereby ensuring a delay of less than 3 seconds, solving the current technical problem of abnormal response delay.

[0014] In some optional embodiments, the current navigation attitude data includes: Bow angle, roll angle, and pitch angle.

[0015] In some optional embodiments, the step of compressing the navigation status data includes: Based on the current navigation attitude data and the previously collected historical navigation attitude data, the amount of navigation attitude change is determined; Determine the corresponding dynamic grid number information based on the current location information; The navigation state data is generated based on the navigation attitude change and the dynamic grid number information; wherein both the dynamic grid number information and the navigation attitude change are 2 bytes in size. A collaborative compression mechanism of attitude incremental encoding (Δ encoding) and position grid encoding is designed to compress a single set of attitude data from 35 bytes to ≤4 bytes (compression ratio >8:1), solving the problem of wasted data.

[0016] In some optional embodiments, the changes in sailing attitude include a dataset consisting of changes in bow angle, roll angle, and pitch angle.

[0017] In some optional embodiments, the compressed navigation status data or the current navigation attitude data is sent to the external communication object via the BeiDou short message module; wherein: The BeiDou short message module includes a first communication channel for transmitting compressed navigation status data and a second communication channel for transmitting complete navigation status data. A dual-SIM redundant channel is adopted, with the first and second communication channels (e.g., SIM 1 and SIM 2) sharing the same BeiDou radio frequency front-end. Channel switching is achieved through Time Division Multiple Access (TDMA). SIM 1 is used to upload positioning grid + attitude Δ values, while SIM 2 is used to upload full abnormal data.

[0018] In some optional embodiments, determining the data transmission strategy based on the prediction result includes: Based on the ship's current speed, a roll attitude warning threshold and a corresponding warning frequency are determined using a preset warning threshold lookup table. Based on the prediction results and the roll attitude warning threshold, determine whether an anomaly has occurred; Based on the judgment result, the data transmission strategy is determined.

[0019] In some optional embodiments, the data transmission strategy includes a full data transmission strategy and a compressed data transmission strategy; wherein: If the determination result does not meet the preset warning conditions, the data transmission strategy will be determined as the compressed data transmission strategy; If the determination result meets the preset warning conditions, the data transmission strategy will be determined as the complete data transmission strategy.

[0020] In some optional embodiments, the method further includes: Under the compressed data transmission strategy, the compressed navigation status data is sent to the external communication object through the first communication channel at the warning frequency. Under the complete data transmission strategy, the complete navigation status data is sent to the external communication object via the second communication channel according to the warning frequency. Currently, with manually set fixed transmission intervals (e.g., 60 seconds), the alarm delay is >15 seconds when the roll exceeds 5°, and maritime accident reports show that nearly one-third of listing accidents are caused by alarm delays. This application addresses the deficiency of abnormal response delay by using a second communication channel specifically for the transmission of full abnormal data.

[0021] In some optional embodiments, the step of performing anomaly prediction processing on the current navigation attitude data includes: Based on the current navigation attitude data and a preset number of historical navigation attitude data, anomaly prediction is performed using a trained LSTM neural network to obtain the prediction result.

[0022] In some optional embodiments, sending the current navigation attitude data to an external communication object includes: Based on the current navigation attitude data and the current time, complete navigation attitude data is generated and sent to the external communication object. When the change in navigation attitude meets the preset alarm conditions, such as an abnormal state (roll ≥ 5°), full transmission is triggered, and a timestamp is added to the data to be transmitted. Attached Figure Description

[0023] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0024] Figure 1 A flowchart of a ship attitude data transmission method provided in this embodiment of the disclosure. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand the present invention. However, the technical solutions claimed in the present invention can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0026] Example 1: The embodiments of the present invention relate to a method for transmitting ship attitude data.

[0027] The following is a detailed description of the implementation details of the ship attitude data transmission method in this embodiment. The following content is only for the convenience of understanding and is not necessary for implementing this solution.

[0028] The ship attitude data transmission method of this embodiment can be applied to electronic devices with communication, computing, and data storage capabilities. For example... Figure 1 As shown, the ship attitude data transmission method provided in this embodiment includes the following steps: Step 110: Collect the ship's current navigation attitude data in real time, and generate navigation status data based on the current navigation attitude data and the ship's current position information.

[0029] The ship's current navigation attitude data is collected in real time by using a Beidou dual-antenna positioning module and a MEMS tilt sensor, and navigation status data is generated.

[0030] Step 120: Compress the navigation status data to obtain compressed navigation status data.

[0031] Step 130: Perform anomaly prediction processing on the current navigation attitude data to obtain the prediction result.

[0032] The generated navigation status data undergoes further compression and anomaly prediction processing. The compression process aims to reduce a single set of attitude data from 35 bytes to ≤4 bytes (compression ratio >8:1); the anomaly prediction process aims to control the alarm delay to ≤3 seconds when the ship's roll / pitch exceeds the threshold.

[0033] Step 140: Determine the data transmission strategy based on the prediction results, and select to send the compressed navigation status data or the current navigation attitude data to the external communication object based on the data transmission strategy.

[0034] Based on real-time acquisition of the ship's current navigation attitude data, and in conjunction with data transmission strategies, it is determined how to send compressed navigation status data or the current navigation attitude data to external communication objects.

[0035] In this method, when no anomalies are detected, only compressed navigation status data is sent. When an anomaly occurs, not only is compressed navigation status data sent, but the prediction results are also promptly fed back to external communication objects. The prediction results may include early warning information with complete navigation attitude data. Furthermore, external communication objects can be external monitoring systems, such as ship performance monitoring systems, cargo status monitoring systems, or third-party maritime analysis and service companies. Compared to existing technologies, the ship attitude data transmission method provided in this embodiment improves bandwidth utilization: it shortens the short message length, increasing the amount of attitude data that can be transmitted by 8 times, meeting the high-frequency sampling requirements of high-speed ships; and it enhances safety: when the ship's roll exceeds a threshold, alarm information prioritizes the use of a dedicated communication channel, thus ensuring a delay of less than 3 seconds and solving the current technical problem of delayed anomaly response.

[0036] Example 2: Based on the above embodiments, this embodiment further explains and illustrates the ship attitude data transmission method provided in the above embodiments.

[0037] In step 110: The ship's current navigation attitude data is collected in real time, and navigation status data is generated based on the current navigation attitude data and the ship's current position information.

[0038] The ship's current navigation attitude data is collected in real time by using a Beidou dual-antenna positioning module and a MEMS tilt sensor, and navigation status data is generated.

[0039] The ship's current location and speed can both be determined using the BeiDou positioning module.

[0040] In some embodiments, the current navigation attitude data includes: Bow angle, roll angle, and pitch angle.

[0041] For example, based on the BeiDou dual-antenna positioning module, the bow angle of the ship can be collected in real time (accuracy 0.1°); based on the MEMS tilt sensor, the roll angle and / or pitch angle of the ship can be collected (accuracy 0.5°).

[0042] In step 120: the navigation status data is compressed to obtain compressed navigation status data.

[0043] In step 130: anomaly prediction processing is performed on the current navigation attitude data to obtain prediction results.

[0044] The generated navigation status data undergoes further compression and anomaly prediction processing. The compression process aims to reduce a single set of attitude data from 35 bytes to ≤4 bytes (compression ratio >8:1); the anomaly prediction process aims to control the alarm delay to ≤3 seconds when the ship's roll / pitch exceeds the threshold.

[0045] In some embodiments, the step of compressing the navigation status data includes: Based on the current navigation attitude data and the previously collected historical navigation attitude data, the amount of navigation attitude change is determined; Determine the corresponding dynamic grid number information based on the current location information; The navigation state data is generated based on the navigation attitude change and the dynamic grid number information; wherein, the dynamic grid number information and the navigation attitude change are both 2 bytes in size.

[0046] In some embodiments, the changes in sailing attitude include a dataset consisting of changes in bow angle, changes in roll angle, and changes in pitch angle.

[0047] Among them, when performing high-ratio compression: The compression goal is to compress a single set of attitude data from 35 bytes to ≤4 bytes (compression ratio >8:1); the implementation method is to design a collaborative compression mechanism of attitude incremental coding (Δ coding) and position grid coding.

[0048] Leveraging the strong correlation between a ship's movement status over short periods and distances, and utilizing the highly structured nature of NMEA (National Marine Electronics Association) statements, predictable fields (such as statement headers, delimiters, units, and checksums) and slowly changing fields (such as position) are significantly simplified or differentially encoded.

[0049] For example, in related technologies, the conventional approach for the eight key parameters of a ship—time, longitude, latitude, speed, heading, bow, pitch angle, and roll angle—is to store and transmit each parameter as a 4-byte single-precision floating-point number, totaling 8 parameters × 4 bytes = 32 bytes.

[0050] In this embodiment, the location information (occupying 2 bytes): longitude and latitude are no longer transmitted as floating-point numbers, but are instead converted into a 2-byte grid number (e.g., i=123, j=45, combined into 12345). This represents a grid of approximately 1.85km × 1.85km, with the accuracy meeting monitoring requirements.

[0051] Attitude data (1.5 bytes): Δ Heading: Range -3.2° to +3.2°, precision 0.1°, 65 states, represented by 5 bits. Δ Pitch (Pitch): Same as above, represented by 5 bits. Δ Roll: Range -3.2° to +3.2°, precision 0.1°, represented by 6 bits (a slightly larger range is given because roll is more critical for safety). The three data points total 16 bits, or 2 bytes.

[0052] Time and Status (0.5 bytes): The sequence number of the current data packet within 1 minute is represented by 4 bits (0-15, corresponding to every 4 seconds or a configurable period), and one of the reserved bits can be used to indicate whether it is data triggered by an anomaly.

[0053] Total bytes: 2 bytes (position) + 2 bytes (attitude Δ) = 4 bytes.

[0054] Compression ratio = Total data size (32 bytes) / Compressed data size (4 bytes) = 8 : 1.

[0055] It should also be noted that it supports compatibility with multiple ship types: The objective is to support adaptive compression of attitude data for ships traveling at speeds of 10-40 knots. The implementation involves designing a speed-attitude coupling model, specifically a rule base that dynamically correlates ship speed with attitude monitoring parameters. The core of this model is to divide the monitoring strategy into multiple discrete "speed-attitude" levels based on the differences in ship attitude motion characteristics at different speeds. Each level has a preset corresponding attitude anomaly threshold and baseline data transmission strategy. Its key function is to achieve adaptive adjustment of the compression strategy and alarm sensitivity, addressing the problem that a single strategy cannot adapt to different ship types and speeds while maintaining a balance between safety and efficiency. Specifically: at low speeds, the focus is on bandwidth efficiency, using more lenient thresholds and lower transmission frequencies. At high speeds, the focus is on navigation safety, using stricter thresholds and more proactive predictive triggering mechanisms.

[0056] In some embodiments, based on the ship's speed, a roll attitude warning threshold and a warning frequency corresponding to the roll attitude warning threshold are determined by a preset warning threshold lookup table.

[0057] In some possible scenarios, based on the ship's speed, a pre-set warning threshold table can be used to determine the pitch attitude warning threshold and the corresponding warning frequency.

[0058] The preset warning threshold lookup table includes the relationship between the 'variable' of airspeed and the roll attitude warning threshold, pitch attitude warning threshold, and warning frequency. In other words, the roll attitude warning threshold, pitch attitude warning threshold, and warning frequency can be determined based on airspeed.

[0059] In some optional embodiments, determining the data transmission strategy based on the prediction result includes: Based on the ship's current speed, a roll attitude warning threshold and a corresponding warning frequency are determined using a preset warning threshold lookup table. Based on the prediction results and the roll attitude warning threshold, determine whether an anomaly has occurred; Based on the judgment result, the data transmission strategy is determined.

[0060] In some optional embodiments, the data transmission strategy includes a full data transmission strategy and a compressed data transmission strategy; wherein: If the determination result does not meet the preset warning conditions, the data transmission strategy will be determined as the compressed data transmission strategy; If the determination result meets the preset warning conditions, the data transmission strategy will be determined as the complete data transmission strategy.

[0061] The preset warning condition can be set to a roll angle not less than the roll attitude warning threshold (for example, the roll attitude warning threshold can be set to 5°); of course, in some possible cases, the warning condition can also be set based on the pitch angle.

[0062] In some optional embodiments, the method further includes: Under the compressed data transmission strategy, the compressed navigation status data is sent to the external communication object through the first communication channel at the warning frequency. Under the complete data transmission strategy, the complete navigation status data is sent to the external communication object through the second communication channel according to the warning frequency.

[0063] Specifically, this coupled model dynamically adjusts two core parameters—the safety threshold (absolute roll threshold) and the compression granularity (normal transmission strategy)—through the key variable of speed, thereby achieving a self-balance between safety and efficiency. Essentially, the model is a set of preset rules, with the core linkage being: increased speed → decreased safety threshold & increased data transmission frequency (i.e., finer compression granularity).

[0064] a. Coupling of speed and safety threshold: The higher the speed, the smaller the stability margin against capsizing. Therefore, the model sets a more stringent attitude warning threshold at high speeds (e.g., 3°) than at low speeds (e.g., 5°), thus enabling proactive safety warnings.

[0065] b. Coupling of speed and compressibility: "Compression granularity" refers to the degree to which the system compromises data accuracy.

[0066] At low speeds, the model allows for coarse-grained compression, which uses longer transmission cycles (e.g., 60 seconds), significantly sacrificing data update rates in exchange for maximum bandwidth savings.

[0067] At high speeds, the model switches to fine-grained compression or even lossless transmission, ensuring the integrity and immediacy of abnormal data through real-time monitoring and triggering. At this point, bandwidth efficiency gives way to security.

[0068] For example, in typical low-speed scenarios, the system automatically applies the "<10 knots" rating, sets the roll threshold to 5°, and sets the transmission cycle to 60 seconds. This matches its slow swaying and bandwidth-sensitive characteristics. In typical high-speed scenarios, the system automatically applies the ">20 knots" rating, tightens the roll threshold to 3°, and enables real-time monitoring and predictive triggering. This, in turn, matches its fast response and high security requirements.

[0069] When performing anomaly prediction processing: Objective: When the roll / pitch exceeds the threshold, the alarm delay is ≤3 seconds; the implementation method is: to establish a trigger-based transmission strategy based on Kalman filter prediction. The core of this trigger-based transmission strategy is to change "post-event reporting" to "pre-event prediction", thereby achieving an alarm delay of ≤3 seconds. The specific strategy includes: (1) Prediction mechanism: using Kalman filter to predict the roll / pitch angle of the ship in real time. This algorithm is based on historical attitude data and ship motion model, and can filter out noise and output the attitude prediction value for the next 1-3 seconds. (2) Trigger logic: the system compares the predicted value with the dynamic threshold of the speed adaptation. Once it is predicted that the threshold will be exceeded, the transmission is triggered immediately, instead of waiting for the abnormality to actually occur. (3) Priority transmission: after triggering, the system immediately switches to the redundant communication channel dedicated to alarms and prioritizes sending alarm information containing complete data to avoid competing for bandwidth with regular data.

[0070] For example, suppose the ship's roll threshold is set to 3 degrees. When the Kalman filter predicts that the roll will exceed the threshold in 2.5 seconds (when the actual roll may only be 1.8 degrees), the system will immediately complete the decision, channel switching, and data transmission within 0.5 seconds. The total time from prediction triggering to alarm delivery is controlled within 3 seconds, while the delay from the actual occurrence of the anomaly to the alarm is almost zero.

[0071] In step 140: a data transmission strategy is determined based on the prediction result, and the compressed navigation status data or the current navigation attitude data is selected to be sent to an external communication object based on the data transmission strategy.

[0072] Based on real-time acquisition of the ship's current navigation attitude data, and in conjunction with data transmission strategies, it is determined how to send compressed navigation status data or the current navigation attitude data to external communication objects.

[0073] In some embodiments, sending the current navigation attitude data to an external communication object includes: Based on the current navigation attitude data and the current time, complete navigation attitude data is generated and sent to the external communication object. Specifically, if no anomaly is detected, compressed navigation status data is sent; if an anomaly occurs, complete navigation attitude data is sent.

[0074] In some embodiments, the compressed navigation status data or the current navigation attitude data is sent to the external communication object via the BeiDou short message module; wherein: The BeiDou short message module includes: a first communication channel for transmitting compressed navigation status data and a second communication channel for transmitting complete navigation status data.

[0075] In some embodiments, the step of performing anomaly prediction processing on the current flight attitude data includes: Based on the current navigation attitude data and a preset number of historical navigation attitude data, anomaly prediction is performed using a trained LSTM (Long Short-Term Memory) neural network to obtain the prediction result. The preset number can be 10, or it can be the amount of data collected within a certain time period (e.g., 5 or 10 seconds), or it can be set according to actual needs.

[0076] Specifically, anomaly prediction is performed based on the current navigation attitude data corresponding to the navigation status data and a preset number of historical navigation attitude data.

[0077] Among them, the preset number of historical navigation attitude data is the preset number of historical navigation attitude data that is closest to the current moment.

[0078] In some embodiments, the method further includes: When the change in navigation attitude meets the preset alarm conditions, complete navigation attitude data is generated based on the current navigation attitude data and the current time, and the complete navigation attitude data is sent to the external communication object.

[0079] The preset alarm condition can be set to a roll angle not less than the roll attitude warning threshold (for example, the roll attitude warning threshold can be set to 5°), or it can be set based on the pitch angle.

[0080] The ship attitude data transmission method provided in this application embodiment improves bandwidth utilization compared to the prior art: it shortens the short message length, increasing the amount of attitude data that can be transmitted by 8 times, meeting the high-frequency sampling requirements of high-speed ships; it enhances safety: when the ship's roll exceeds the threshold, the alarm information uses a dedicated communication channel first, thereby ensuring a delay of less than 3 seconds, solving the current technical problem of abnormal response delay.

[0081] Example 3: Based on the above embodiments, this embodiment provides a ship attitude data transmission system, including: A communication device used to communicate with external communication objects; Data acquisition device, used to collect the ship's current navigation attitude data in real time; The controller is communicatively connected to both the data acquisition device and the communication device, and is configured to: generate navigation status data based on the ship's current position information and the current navigation attitude data; compress the navigation status data to obtain compressed navigation status data; perform anomaly prediction processing on the current navigation attitude data to obtain a prediction result; determine a data transmission strategy based on the prediction result, and select to send the compressed navigation status data or the current navigation attitude data to an external communication object based on the data transmission strategy.

[0082] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the controller described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0083] Example 4: Based on the above embodiments, this embodiment provides an example of a specific ship attitude data transmission system.

[0084] 1. Regarding the overall system architecture: (1) For the data sensing layer, namely the data acquisition device: Based on the BeiDou dual-antenna positioning module, it outputs the heading angle in real time (accuracy 0.1°). Based on MEMS tilt sensing, it outputs roll / pitch (accuracy 0.5°).

[0085] (2) For the controller, this is the data compression and anomaly detection layer: a. Attitude compression processor: Δ encoding module: calculates attitude change; b. Anomaly detection module: Based on LSTM to predict attitude changes; c. Grid mapping engine: Location information (e.g., latitude and longitude coordinates) → Grid number.

[0086] The core function of this grid mapping engine is to convert continuous, high-precision latitude and longitude coordinates into discrete, short-byte grid numbers to achieve efficient compression of location data. Its specific mapping mechanism is based on a dynamic virtual grid with the ship's initial position or previous valid position as the reference origin. This grid covers a defined area (e.g., a circular area with a radius of 5 nautical miles). The system divides the entire geographic space into countless tiny square grid cells, each with a predefined side length (e.g., 0.01 degrees, approximately 1.85 kilometers). Through this process, latitude and longitude information that would normally require approximately 12 bytes of transmission (such as the "DDDMM.MMMM" format in NMEA statements) is compressed into a grid number occupying only 2 bytes, thus significantly saving communication bandwidth.

[0087] (3) For the data transmission layer of the communication device: The BeiDou-3 short message module has dual redundant channels (Card 1 transmits positioning grid + attitude Δ value, Card 2 transmits full abnormal data).

[0088] 2. Core Algorithm Design: (1) Hybrid compression coding algorithm: a. Position compression: using dynamic mesh coding. def grid_encode(lon, lat): R = 5# Dynamic mesh with a radius of 5 nautical miles grid_size = 0.01# Approximately 1.85km / grid i = int((lon - ref_lon) / grid_size) # ref_lon is the initial longitude of the ship j = int((lat - ref_lat) / grid_size) return i * 1000 + j# Grid number (2 bytes) b. Attitude compression: (a) Normal state (roll <5°): Δ encoding is used to transmit only the change; Attitude Δ value = [Δ heading, Δ roll, Δ pitch]; Δ value range: -3.2°~+3.2°, precision 0.1° → 5 bits per parameter (15 bits in total).

[0089] (b) Abnormal state (roll ≥ 5°): Trigger full transmission and add the timestamp corresponding to the current time; Abnormal data packet = [flag 0xFF, timestamp, heading angle, roll angle, pitch angle].

[0090] (2) Exception triggering mechanism: a. Prediction Model: Real-time prediction of attitude change trends based on LSTM network: def lstm_alert(roll_angle): # Input: Roll sequence of the last 10 seconds → Output: Predicted value for the next 3 seconds if predicted_roll>= 5.0:# Trigger transmission ahead of schedule send_full_data() The prediction model in this embodiment is a dedicated LSTM network with a lightweight design and data optimization using a pre-processed Kalman filter. It is deeply integrated into an automated triggering decision system. Through this series of targeted optimizations and system-level designs, the practical engineering challenge of achieving highly reliable, low-latency attitude warnings in resource-constrained shipboard environments is solved. These optimization measures collectively ensure that the final technical effect of "alarm delay ≤ 3 seconds" is achieved. Specifically: Input layer 10 nodes: This means that the model analyzes a continuous time series of length 10 each time. That is, it uses the historical roll angle data of the most recent 10 seconds (one sampling point per second) to gain insight into the current state and short-term trends of the ship's motion.

[0091] Hidden layer 8 nodes: This defines the "complexity" or "capacity" of the model's internal memory and processing states. The 8 nodes form a very compact network, meaning it has sufficient capacity to learn effective patterns of ship roll from 10 seconds of data, while avoiding structural redundancy.

[0092] Output layer 1 node: This indicates that the model's prediction objective is single and specific: the predicted roll angle for the next 3 seconds. This single value is directly used for comparison with multi-level thresholds to drive the triggering decision.

[0093] This streamlined and specialized structure is a key engineering optimization made to achieve the core contradictory goals of "high-precision ultra-short-term prediction" and "extremely low computational latency", and is a necessary guarantee for realizing the technical effect of this invention.

[0094] b. Multi-level thresholds (relevant information can be saved in the preset warning threshold lookup table): Speed ​​< 10 knots, roll threshold 5°, transmission strategy is 60-second cycle; 10 knots < speed knots < 20 knots, roll threshold 4°, transmission strategy is 30-second cycle; Speed ​​> 20 knots, roll threshold 3°, transmission strategy is 1 second, 2 seconds, 5 seconds or real-time monitoring and prediction trigger.

[0095] Specifically, this multi-level threshold mechanism is one of the core components of this system's intelligent adaptive compression and safety monitoring. Its rules are designed so that the higher the ship's speed, the greater the risk of attitude instability, thus requiring more stringent monitoring. Specifically, this mechanism includes three key variables: speed range, absolute roll threshold, and normal transmission strategy.

[0096] (a) Low-speed class (speed <10 knots): Roll absolute threshold: 5.0°. At this speed, the ship's motion is relatively gentle, so a relatively lenient safety boundary is set.

[0097] Normal transmission strategy: 60-second cycle. The system mainly runs a high-compression Δ encoding mode, periodically (every 60 seconds) reporting data through channel 1 to save bandwidth to the greatest extent.

[0098] Triggering condition: When the predicted roll angle is ≥5.0°, an alert is triggered.

[0099] (b) Medium-speed class (speed ≤ 10 knots < 0 knots): Absolute roll threshold: 4.0°. As speed increases, stability requirements rise, and the threshold tightens accordingly.

[0100] Standard transmission strategy: 30-second cycle. Increase the update frequency of routine data to more closely track ship status.

[0101] Triggering condition: When the predicted roll angle is ≥4.0°, an alert is triggered.

[0102] (c) High-speed class (speed ≥ 20 knots): Roll absolute threshold: 3.0°. At high speeds, ships are more sensitive to attitude anomalies, so the most stringent threshold is used to ensure safety.

[0103] Normal transmission strategy: real-time monitoring and predictive triggering. The system relies entirely on predictive models for event-driven transmission and does not perform fixed-period reporting under normal circumstances, thereby ensuring ultimate security response while avoiding unnecessary bandwidth consumption.

[0104] Triggering condition: When the predicted roll angle is ≥3.0°, an alert is triggered.

[0105] In some embodiments, when an early warning is triggered, complete navigation attitude data is generated based on the current navigation attitude data and the current time, and the complete navigation attitude data is sent to the external communication object.

[0106] 3. Hardware optimization design: Dual-card redundant transmission: Card 1: Dedicated to grid number + attitude Δ value (4 bytes / time, 1 time / minute); Card 2: Dedicated to handling abnormal full data (8 bytes / time, triggered on demand).

[0107] Specifically, the dual-SIM time-division multiplexing architecture: SIM 1 and SIM 2 share the same BeiDou RF front-end and switch channels through Time Division Multiple Access (TDMA); Anti-interference circuit design: the digital signal area (Δ encoding module) and the analog signal area (tilt sensor input) can be separated in the PCB layout, and a ferrite magnetic ring is added to suppress common-mode interference.

[0108] Example 5: Another embodiment of this application relates to an electronic device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the ship attitude data transmission method of the above embodiments.

[0109] The memory and processor are connected via a bus, which can include any number of interconnecting buses and bridges, connecting various circuits of one or more processors and memories. The bus can also connect various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and will not be described further herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be a single element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by the processor is transmitted over the wireless medium via an antenna, which further receives data and transmits it to the processor.

[0110] The processor manages the bus and handles general processing, and also provides various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory, on the other hand, is used to store data used by the processor during operation.

[0111] Example 6: Another embodiment of this application relates to a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the method embodiments described above.

[0112] That is, those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0113] In some embodiments of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of the methods described in the above embodiments.

[0114] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing this application, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of this application.

Claims

1. A method for transmitting ship attitude data, characterized in that, include: The ship's current navigation attitude data is collected in real time, and navigation status data is generated based on the current navigation attitude data and the ship's current position information; The navigation status data is compressed to obtain compressed navigation status data; Anomaly prediction processing is performed on the current navigation attitude data to obtain prediction results; Based on the prediction results, a data transmission strategy is determined, and based on the data transmission strategy, the compressed navigation status data or the current navigation attitude data is selected to be sent to an external communication object.

2. The method according to claim 1, characterized in that, The current navigation attitude data includes: Bow angle, roll angle, and pitch angle.

3. The method according to claim 1, characterized in that, The steps for compressing the navigation status data include: Based on the current navigation attitude data and the previously collected historical navigation attitude data, the amount of navigation attitude change is determined; Determine the corresponding dynamic grid number information based on the current location information; The navigation state data is generated based on the navigation attitude change and the dynamic grid number information; wherein, the dynamic grid number information and the navigation attitude change are both 2 bytes in size.

4. The method according to claim 3, characterized in that, The changes in the navigation attitude include a dataset consisting of changes in bow angle, roll angle, and pitch angle.

5. The method according to claim 1, characterized in that, Sending the current navigation attitude data to an external communication object includes: Based on the current navigation attitude data and the current time, complete navigation attitude data is generated and sent to the external communication object.

6. The method according to claim 1, characterized in that, The step of determining the data transmission strategy based on the prediction results includes: Based on the ship's current speed, a roll attitude warning threshold and a corresponding warning frequency are determined using a preset warning threshold lookup table. Based on the prediction results and the roll attitude warning threshold, determine whether an anomaly has occurred; Based on the judgment result, the data transmission strategy is determined.

7. The method according to claim 6, characterized in that, The data transmission strategy includes a full data transmission strategy and a compressed data transmission strategy; wherein: If the determination result does not meet the preset warning conditions, the data transmission strategy will be determined as the compressed data transmission strategy; If the determination result meets the preset warning conditions, the data transmission strategy will be determined as the complete data transmission strategy.

8. The method according to claim 7, characterized in that, The compressed navigation status data or the current navigation attitude data is sent to the external communication object via the BeiDou short message module; wherein: The BeiDou short message module includes: a first communication channel for transmitting compressed navigation status data and a second communication channel for transmitting complete navigation status data.

9. The method according to claim 8, characterized in that, The method further includes: Under the compressed data transmission strategy, the compressed navigation status data is sent to the external communication object through the first communication channel at the warning frequency. Under the complete data transmission strategy, the complete navigation status data is sent to the external communication object through the second communication channel according to the warning frequency.

10. A ship attitude data transmission system, characterized in that, include: A communication device used to communicate with external communication objects; Data acquisition device, used to collect the ship's current navigation attitude data in real time; The controller is communicatively connected to both the data acquisition device and the communication device, and is configured to: generate navigation status data based on the ship's current position information and the current navigation attitude data; compress the navigation status data to obtain compressed navigation status data; perform anomaly prediction processing on the current navigation attitude data to obtain a prediction result; determine a data transmission strategy based on the prediction result, and select to send the compressed navigation status data or the current navigation attitude data to an external communication object based on the data transmission strategy.

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