Laser synchronous monitoring method and system for safety angle and speed of ship berthing and leaving

Abstract

The application relates to the technical field of ship berthing and unberthing safety monitoring, and discloses a laser synchronous monitoring method and system for a ship berthing and unberthing safety angle and speed, wherein the method comprises the following steps: acquiring multi-source original laser echo data; performing a synchronous candidate echo set construction task; performing a physical consistency feature construction task; performing a purification preprocessing task; performing a berthing and unberthing state monitoring task; performing delay compensation early warning processing and result output; and outputting a hierarchical early warning result. Compared with the prior art which mainly relies on a single-point laser ranging scheme and cannot effectively distinguish real ship body echoes from water surface mirror reflection false echoes under the conditions of strong reflection on a port water surface, wet mist attenuation and multiple path false echoes prone to occur when a ship body is at low speed during berthing and unberthing. According to the application, the berthing and unberthing states during the berthing and unberthing process of a ship body are synchronously monitored by constructing a synchronous candidate echo set and combining a multi-candidate echo confidence screening mechanism.

Description

Technical Field

[0001] This invention relates to the field of ship berthing and unberthing safety monitoring technology, and in particular to a laser synchronous monitoring method and system for ship berthing and unberthing safety angles and speeds. Background Technology

[0002] Currently, in the field of port vessel berthing and departure safety monitoring, common technical solutions mainly include monitoring the distance and movement status between vessels and the dock using methods such as video image recognition, single-point laser ranging, and radar ranging. Among these, video image-based monitoring methods are easily affected by changes in lighting, obstructions, and weather conditions, resulting in poor stability; while single-point laser ranging methods have high ranging accuracy, they usually rely on a single echo result and lack the ability to discern complex echo environments; radar methods, on the other hand, suffer from relatively low resolution and difficulty in accurately reflecting the detailed berthing status.

[0003] Furthermore, in actual port berthing and unberthing scenarios, due to significant water surface fluctuations, specular reflections, and wind and wave disturbances, laser signals are prone to multipath reflections during propagation. This results in the laser ranging equipment receiving echoes that simultaneously contain both genuine ship-reflected echoes and spurious echoes formed by water surface reflections. In addition, under environmental conditions such as fog and high humidity, the attenuation effect during laser propagation is further amplified, making the echo intensity distribution more complex. Traditional processing methods based on fixed thresholds or simple filtering strategies are insufficient to effectively distinguish between genuine and interfering echoes. For example, during low-speed berthing of a ship, as the distance between the ship and the dock gradually decreases, the difference between the water surface reflection path and the ship's reflection path narrows. Some spurious echoes are highly similar to genuine echoes in distance and intensity, leading to situations where existing technologies are prone to jumps in ranging results, misjudgments, or even the loss of crucial distance information.

[0004] Therefore, existing technologies cannot fully meet the demand for high-precision and stable acquisition of real distance information and motion status of ships under complex water surface reflection environments and dynamic berthing and unberthing conditions. Thus, there is an urgent need for a method that can still effectively identify real laser echoes and synchronously monitor the safe angles and speeds of ships during berthing and unberthing, even under complex conditions such as highly reflective water surfaces, multipath interference, and environmental attenuation, in order to improve the accuracy of safety monitoring and the reliability of early warnings during ship berthing and unberthing processes. Summary of the Invention

[0005] To address the aforementioned technical shortcomings, the purpose of this invention is to propose a laser synchronous monitoring method for the safety angle and speed of ships berthing and unberthing. This method aims to solve the technical problem that existing technologies mainly rely on single-point laser ranging schemes, which are particularly problematic under conditions of strong water surface reflection, damp fog attenuation, and the susceptibility of multipath false echoes when ships berth and unberth at low speeds. These methods cannot effectively distinguish between real ship echoes and false echoes from water surface reflections.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention provides a laser synchronous monitoring method for the safety angle and speed of ships berthing and unberthing.

[0007] The laser-synchronized monitoring method for ship berthing and unberthing safety angles and speeds includes: Step S10: Obtain multi-source raw laser echo data, laser ranging unit installation parameters, and environmental parameters of the target vessel during the berthing or departure monitoring period. Combine the unified time reference reconstruction and candidate echo spatial mapping mechanism to perform the synchronous candidate echo set construction task and output the synchronous candidate echo set. Step S20: Based on the synchronous candidate echo set, the physical consistency feature construction task is performed using the environmental attenuation compensation and incident angle intensity consistency characterization mechanism, and the physical consistency feature set is output. Step S30: Based on the physical consistency feature set, perform the purification preprocessing task using temporal consistency constraints and a multi-candidate echo confidence screening mechanism, and output the purification distance observation set; Step S40: Execute the berthing and departure status monitoring task based on the purification distance observation set, and output the berthing and departure risk status set; Step S50: Perform delay compensation early warning processing and output the results based on the berthing and departure risk status set, and output the graded early warning results.

[0008] Preferably, step S10 specifically includes: Step S101: Obtain the raw laser echo data output by multiple laser ranging units deployed at intervals along the berthing shoreline during the target monitoring period. The raw laser echo data includes at least candidate echo ranging values, candidate echo intensity values, and sampling timestamps. Also, obtain the installation position parameters and emission direction parameters of each laser ranging unit in the wharf reference coordinate system. Step S102: Based on the sampling timestamps of each laser ranging unit, perform fixed clock offset compensation and clock drift compensation on the original laser echo data to construct a synchronous echo sequence under a unified time reference; Step S103: Based on the synchronous echo sequence under a unified time reference and the installation position parameters and emission direction parameters of each laser ranging unit, the synchronous echo sequence is mapped to candidate spatial points under the dock reference coordinate system, and the synchronous candidate echo set is output.

[0009] Preferably, step S20, which involves constructing a physical consistency feature set based on the synchronous candidate echo set using an environmental attenuation compensation and incident angle intensity consistency characterization mechanism, specifically includes: Step S201: Obtain visibility parameters, humidity parameters, wave height values, and wind and wave disturbance parameters, and construct equivalent environmental attenuation parameters for the current monitoring time based on the visibility parameters, humidity parameters, wave height values, and wind and wave disturbance parameters; Step S202: Input the synchronous candidate echo set into the preset local plane model of the hull side, and the local plane model of the hull side outputs the corresponding incident angle parameters; and construct the theoretical echo intensity estimate based on the equivalent environmental attenuation parameters, candidate echo ranging values ​​and incident angle parameters by using a coupled representation method of propagation attenuation term and angle reflection term. Step S203: Obtain the measured intensity values ​​of candidate echoes, and construct a physical consistency feature set based on the deviation between the measured intensity values ​​of candidate echoes and the theoretical echo intensity estimates.

[0010] Preferably, in step S202, a theoretical echo intensity estimate is constructed based on the equivalent environmental attenuation parameter, candidate echo ranging value, and incident angle parameter using a coupled representation method of propagation attenuation term and angular reflection term, specifically including: The laser round-trip propagation path length is constructed based on the candidate echo ranging values, and the distance attenuation contribution is constructed based on the laser round-trip propagation path length. Construct the environmental loss contribution based on the equivalent environmental attenuation parameters; The angle reflection contribution between the laser incident direction and the normal of the local surface of the hull side is constructed based on the incident angle parameter. The angle reflection contribution is used to represent the degree of influence of the hull surface on the laser echo intensity. The distance attenuation contribution, environmental loss contribution, and angular reflection contribution are coupled together to obtain a theoretical echo intensity estimate. The theoretical echo intensity estimate is used to reflect the distance attenuation characteristics, environmental attenuation characteristics, and angular reflection characteristics of the candidate echo in the current strong reflection environment of the port water surface.

[0011] Preferably, step S30, which involves performing a pre-processing cleanup task based on the physical consistency feature set using temporal consistency constraints and a multi-candidate echo confidence screening mechanism, and outputting a cleanup distance observation set, specifically includes: Step S301: Obtain the ship berthing and departure status results at historical moments, and construct the predicted distance result at the current monitoring moment using a long short-term memory network based on the ship berthing and departure status results at historical moments; obtain the current candidate echo ranging value, and construct a temporal consistency residual based on the difference between the current candidate echo ranging value and the predicted distance result; Step S302: Based on the physical consistency feature set and temporal consistency residual, calculate the true echo confidence score for multiple candidate echoes corresponding to each laser ranging unit; Step S303: The candidate echo whose true echo confidence score is greater than the preset confidence threshold and is the best among multiple candidate echoes in the corresponding laser ranging unit is determined as the true echo of the target, and the ranging value corresponding to the true echo of the target is constructed as a purification distance observation set.

[0012] Preferably, step S40, which involves performing berthing / departure status monitoring based on the purification distance observation set and outputting a berthing / departure risk status set, specifically includes: Input the purification distance observation set into the preset state monitoring model, and jointly estimate the normal distance, normal velocity, attitude angle and angular velocity of the target ship at the current monitoring time to obtain the berthing and departure state results; Based on the berthing and departure status results, the berthing and departure movement trend of the target vessel relative to the dock reference line is calculated, and a risk assessment result is generated based on the berthing and departure movement trend. Based on the normal distance, normal velocity, attitude angle, angular velocity, and risk assessment results, a set of berthing and unberthing risk states is constructed.

[0013] Preferably, step S50, which involves performing delay compensation early warning processing and outputting the results based on the berthing / departure risk state set, specifically includes: Step S501: Obtain the acquisition delay, communication delay, calculation delay and output delay in the current monitoring link, and construct the delay compensation state result in combination with the berthing and departure risk state set; Step S502: Based on the delay compensation state results, use the state extrapolation prediction method to calculate the risk assessment results for future times, and generate graded early warning results based on the risk assessment results for future times; Step S503: Output the graded early warning result, which includes at least one of the following: normal monitoring status, first-level early warning status, second-level early warning status, and third-level emergency early warning status.

[0014] This invention also provides a laser synchronous monitoring system for the safety angle and speed of ships berthing and unberthing, comprising: The synchronous candidate echo set construction module is used to acquire multi-source raw laser echo data, laser ranging unit installation parameters, and environmental parameters of the target vessel during the berthing or departure monitoring period. It combines the unified time reference reconstruction and candidate echo spatial mapping mechanism to perform the synchronous candidate echo set construction task and output the synchronous candidate echo set. The physical consistency feature construction module is used to perform the physical consistency feature construction task based on the synchronous candidate echo set, using an environmental attenuation compensation and incident angle intensity consistency characterization mechanism, and output a physical consistency feature set. The purification distance observation set construction module is used to perform purification preprocessing tasks based on the physical consistency feature set, using temporal consistency constraints and a multi-candidate echo confidence screening mechanism, and output the purification distance observation set. The berthing and unberthing status monitoring module is used to perform berthing and unberthing status monitoring tasks based on the purification distance observation set and output the berthing and unberthing risk status set; The graded early warning output module is used to perform delay compensation early warning processing and output the results based on the berthing and departure risk status set, and output graded early warning results.

[0015] The present invention also provides a laser synchronous monitoring device for the safe angle and speed of berthing and unberthing of ships, comprising: a memory, a processor, and a laser synchronous monitoring program for the safe angle and speed of berthing and unberthing of ships stored in the memory and executable on the processor. When the laser synchronous monitoring program for the safe angle and speed of berthing and unberthing of ships is executed by the processor, a laser synchronous monitoring method for the safe angle and speed of berthing and unberthing of ships is realized.

[0016] The present invention also provides a computer program product, including a laser synchronous monitoring program for the safe angle and speed of berthing and unberthing of ships. When the laser synchronous monitoring program for the safe angle and speed of berthing and unberthing of ships is executed by a processor, it implements the laser synchronous monitoring method for the safe angle and speed of berthing and unberthing of ships.

[0017] The beneficial effects of this invention are as follows: By introducing an environmental attenuation compensation and incident angle intensity consistency characterization mechanism, this invention jointly models the propagation path attenuation characteristics, environmental attenuation characteristics, and angle reflection characteristics of candidate echoes, and constructs physical consistency characteristics by combining the deviation between measured echo intensity and theoretical echo intensity. This enables the effective differentiation between real ship echoes and false echoes generated by water surface specular reflection in complex environments such as strong reflection on port water surfaces, wave disturbances, and fog attenuation. It avoids the misjudgment problems caused by traditional single threshold or mean filtering methods, and significantly improves the authenticity and stability of laser ranging results.

[0018] This invention constructs a multi-candidate echo confidence screening mechanism based on temporal consistency constraints and performs synchronous calculation of berthing and departure states by combining a clean distance observation set. This enables continuous and stable monitoring of the ship's normal distance, normal velocity, attitude angle, and angular velocity. Furthermore, it introduces a delay compensation early warning processing mechanism to predict the risk state at future moments. This effectively avoids the problems of measurement jumps, early warning lags, and discontinuous state estimation in traditional berthing monitoring systems, thereby improving the safety monitoring accuracy and real-time early warning capability during the ship's berthing and departure processes. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart illustrating the first embodiment of a laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds according to the present invention.

[0021] Figure 2 This is a schematic diagram of the equipment for a laser synchronous monitoring method for the safety angle and speed of a ship berthing and unberthing according to the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1: As Figure 1 The diagram shown is a flowchart of the first embodiment of the laser synchronous monitoring method for the safe angle and speed of a ship berthing and unberthing according to the present invention. The first embodiment of the laser synchronous monitoring method for the safe angle and speed of a ship berthing and unberthing according to the present invention is presented.

[0024] In the first embodiment, the laser synchronous monitoring method for the safe angle and speed of a ship berthing and unberthing includes: Step S10: Obtain multi-source raw laser echo data, laser ranging unit installation parameters, and environmental parameters of the target vessel during the berthing or departure monitoring period. Combine the unified time reference reconstruction and candidate echo spatial mapping mechanism to perform the synchronous candidate echo set construction task and output the synchronous candidate echo set.

[0025] It's important to note that this step isn't simply about stitching together data from multiple laser ranging units. Instead, it addresses the fundamental issue that "different devices don't see the same physical moment." While a ship's overall speed is low during berthing or unberthing, the hull continuously experiences lateral movement, slight angular changes, and localized swaying. If there's a millisecond-level deviation in the sampling times of different laser ranging units, this deviation will be amplified during subsequent angle calculations, leading to distortion in the ship's attitude assessment at the same moment. Therefore, this step first acquires candidate echo ranging values, candidate echo intensity values, and sampling timestamps from multiple laser ranging units. Then, combining the installation position and emission direction of each laser ranging unit in the dock's reference coordinate system, the originally scattered local measurement results are organized under a unified spatiotemporal reference, ultimately forming a synchronized candidate echo set that can be directly accessed in subsequent steps.

[0026] Understandably, the "candidate echoes" here do not presuppose that any one of them is a true ship echo. Instead, they intentionally retain multiple echo results that may appear from the same laser ranging unit at the same monitoring time. This is because in the highly reflective water environment of a port, specular reflection from the water surface, wave crest refraction, and localized scattering from fog can make some false echoes very close in distance to the true ship echo, and even temporarily stronger in intensity. If other candidate echoes were directly deleted during the acquisition phase using the "strongest is true" or "closest is true" approach, there would be no room for error correction later. Therefore, this step outputs a synchronized set of candidate echoes, rather than directly outputting the ship distance result.

[0027] It should be understood that, compared to the traditional approach of using a single device, a single moment, and a single echo directly as the ranging result, the improvement in this step lies not in simply increasing the number of sensors, but in changing the way front-end data enters the subsequent analysis module. Traditional methods often assume that the sampling times of different devices are negligible. This is not a problem in static target measurement, but it does not hold true in continuous motion scenarios such as ship berthing and unberthing. This embodiment reconstructs data from multiple laser ranging units using a unified time reference, bringing the data back to the same physical moment before spatial mapping. Furthermore, it does not rush to delete candidate echoes in this step, but rather incorporates "preserving uncertainty and delaying the decision" as part of the design philosophy. In other words, this step is not for directly calculating the answer, but to preserve sufficient information dimensions for subsequent steps S20 and S30, ensuring that the determination of the true echo is not based on overly simplistic prior assumptions.

[0028] For example, in a scenario where a 50,000-ton bulk carrier is berthing, three laser ranging units are deployed along the shoreline. During a certain monitoring period, the first laser ranging unit outputs two sets of candidate echoes with ranging values ​​of 12.44 meters and 13.09 meters, and sampling timestamps of 10.018 seconds and 10.024 seconds, respectively; the second laser ranging unit outputs two sets of candidate echoes with ranging values ​​of 12.51 meters and 13.16 meters, and sampling timestamps of 10.026 seconds and 10.031 seconds, respectively; the third laser ranging unit outputs one set of candidate echoes with a ranging value of 12.47 meters and a sampling timestamp of 10.017 seconds. Using traditional methods, the first echo from each device is often taken as the effective value, and then the distance difference is calculated. However, this implicitly treats the data at 10.017 seconds, 10.018 seconds, and 10.026 seconds as the same moment, thus introducing error. In this embodiment, clock offset and drift compensation are first performed on each timestamp to unify them to the same common time reference. Then, the above echoes are mapped to candidate spatial points in the dock reference coordinate system in combination with the installation location and transmission direction, and finally a set of synchronous candidate echoes containing multiple candidate points is formed for further judgment in the next step.

[0029] Step S20: Based on the synchronous candidate echo set, the physical consistency feature construction task is performed using the environmental attenuation compensation and incident angle intensity consistency characterization mechanism, and the physical consistency feature set is output.

[0030] It's important to clarify how to distinguish between genuine ship echoes and spurious echoes formed by water surface reflection under conditions of strong reflection. Looking only at the distance measurement value, both types of echoes often appear "real"; looking only at the measured intensity value may also fail to differentiate them, as some spurious echoes may be temporarily stronger due to localized specular reflection. Therefore, this step is not simply a threshold screening of intensity, but rather placing the candidate echo back into its formation process to re-examine whether it conforms to the current environment and the physical reflection laws of the ship's surface. In other words, this step doesn't answer "how strong is this echo?", but rather "in the current environment, does this echo resemble a genuine echo from the ship's surface?"

[0031] Understandably, this step considers both the environmental impact on laser propagation and the influence of the ship's surface on laser reflection. The former is mainly reflected in the propagation loss caused by factors such as visibility, humidity, wave height, and wind and wave disturbance; the latter is mainly reflected in the change of the angle between the laser incident direction and the normal of a local surface on the ship's side. For the same ranging value, if the ambient humidity is higher and the visibility is worse, the echo intensity should theoretically be weaker; for the same environmental conditions, if the incident angle is larger, the effective echo returning from the ship's surface will usually also be weakened. Therefore, this step constructs equivalent environmental attenuation parameters and incident angle parameters, combines them with candidate echo ranging values ​​to form a theoretical echo intensity estimate, and further constructs a physical consistency feature set by analyzing the deviation between the measured intensity values ​​of the candidate echoes and the theoretical echo intensity estimate. For example, continuing the aforementioned scenario, assume that the visibility at the current monitoring time is 700 meters, the humidity is 86%, the wave height is 0.28 meters, and the wind and wave disturbance parameter is 0.37. A laser ranging unit has two candidate echoes: Echo A has a ranging value of 12.44 meters and a measured intensity of 74; Echo B has a ranging value of 13.09 meters and a measured intensity of 81. According to the traditional empirical rule of "higher intensity preferred," Echo B is more likely to be retained. However, in this embodiment, the incident angles of A and B are first obtained as 11 degrees and 33 degrees respectively based on a local planar model of the ship's side. Then, theoretical echo intensity estimates are constructed by combining equivalent environmental attenuation parameters and propagation path length. Calculations show that the measured value of Echo A differs little from the theoretical value, while although Echo B has a higher measured intensity, its intensity deviates more significantly from physical laws due to its larger incident angle and longer propagation path. Therefore, Echo A performs better in terms of physical consistency. In other words, the improvement in this step is not about changing "higher intensity" to "lower intensity," but about changing "intensity value itself" to "whether the intensity conforms to the physical formation mechanism."

[0032] Step S30: Based on the physical consistency feature set, perform the purification preprocessing task using temporal consistency constraints and a multi-candidate echo confidence screening mechanism, and output the purification distance observation set.

[0033] It should be noted that relying solely on physical consistency at a single moment is insufficient to completely resolve misjudgments under highly reflective water surfaces. This is because some false echoes may "just happen" to conform to certain physical characteristics at a single moment, especially when wind and wave changes are relatively gentle or specular reflection conditions are temporarily stable, making single-frame judgments still prone to error. Therefore, this step further utilizes the continuous motion characteristics of the ship's berthing and unberthing processes, introducing temporal consistency into the determination of true echoes. In other words, this step not only concerns itself with "whether the current echo resembles a real echo," but also with "if it is real, whether it connects with the motion trends of previous moments."

[0034] It should be understood that the key improvement of this step compared to traditional formula methods lies in the fact that traditional methods typically treat the time dimension as a post-processing smoothing tool, while this embodiment moves the time dimension forward to become the basis for judgment itself. A common practice in traditional schemes is to first select a "current echo" based on the current intensity or distance rules, and then use moving averages or differential smoothing to correct jitter. This means that once an erroneous echo is selected, subsequent smoothing often only makes the error "smoother," rather than fundamentally correcting it. This embodiment is different; it first uses historical states to construct the current predicted distance result, and then allows this prediction result to participate in the calculation of the true echo confidence score, so that temporal continuity plays a role in the screening stage. In other words, the traditional method is "select first, then smooth," while this embodiment is "judgment and utilization of continuity constraints simultaneously." This improvement makes this step more suitable for handling false echoes during low-speed berthing processes that involve "small distance jumps but disrupted continuity." For example, the normal distances of a ship at the previous five monitoring times were 13.08 meters, 12.95 meters, 12.80 meters, 12.66 meters, and 12.52 meters, showing a stable decreasing trend. Based on these historical results, the Long Short-Term Memory (LSTM) network outputs a predicted distance of 12.39 meters for the current monitoring time. At this time, a laser ranging unit corresponds to three candidate echoes with ranging values ​​of 12.36 meters, 12.88 meters, and 13.14 meters. The physical consistency characteristics output in step S20 show that none of the three are absolutely abnormal, but the echo corresponding to 12.36 meters has the smallest physical deviation, followed by 12.88 meters, and 13.14 meters has the largest. If only intensity is considered, the echo corresponding to 12.88 meters may be stronger; if only distance is considered, 12.36 meters is more reasonable. This embodiment further calculates the temporal consistency residuals of the three relative to the predicted distance result of 12.39 meters, with results of 0.03 meters, 0.49 meters, and 0.75 meters, respectively. After incorporating both physical consistency characteristics and temporal consistency residuals into the true echo confidence score, the echo corresponding to 12.36 meters received the highest overall score and was therefore identified as the true echo of the target, and added to the cleanup distance observation set. The resulting observations can explain both the current physical phenomena and the historical trajectory.

[0035] Step S40: Execute the berthing and unberthing status monitoring task based on the purification distance observation set, and output the berthing and unberthing risk status set.

[0036] It should be noted that after step S30, the data input to this step is no longer the original distance set mixed with multipath false echoes, but a purified distance observation set after filtering. Therefore, the focus of this step is no longer "determining which echo is reliable," but rather using the more reliable observation results to reconstruct the ship's current berthing and unberthing state, and further form a risk representation. The berthing and unberthing risk state set includes at least the normal distance result, normal velocity result, attitude angle result, angular velocity result, and risk assessment result. These state quantities do not exist in isolation, but together characterize the ship's real-time approach situation relative to the dock.

[0037] Understandably, this step inputs the cleanup distance observation set into a pre-set state monitoring model to jointly estimate the normal distance, normal velocity, attitude angle, and angular velocity. The normal distance reflects the proximity between the vessel and the dock, the normal velocity reflects the current rate of approach or departure, the attitude angle reflects the vessel's deflection relative to the shoreline, and the angular velocity reflects whether this deflection is increasing. Subsequently, a risk assessment result is generated based on the combined relationships between these state variables. In actual engineering, a single, small distance value may not necessarily indicate danger, because if the speed is very low and the attitude angle is stable, the vessel may still be in a controlled berthing state; conversely, even if the current distance is not too small, if the normal velocity is high and the attitude angle is still increasing, it is very likely to evolve into a dangerous state in a short period of time. Therefore, this step outputs a set of berthing and departure risk states, rather than a single alarm indicator.

[0038] Step S50: Perform delay compensation early warning processing and output the results based on the berthing and departure risk status set, and output the graded early warning results.

[0039] It's important to note that this step doesn't simply display the risk assessment results from step S40 as is; rather, it further considers the unavoidable delays throughout the entire monitoring chain. For large vessels, even if the total system delay is only a little over 100 milliseconds, if the ship is still approaching the dock at a relatively high normal speed and the attitude deviation continues to increase, then by the time the warning is actually displayed on the interface or transmitted to the auxiliary control system, the actual situation has already progressed to a certain point. Therefore, this step acknowledges the existence of delay and then compensates for this delay in the warning results. In other words, the graded warning results output in this step are not "the past state just calculated at this moment," but rather "a state that is closer to the current true risk after compensating for the delay."

[0040] It should be understood that, compared to the traditional formula-based approach of "alarming when the current value exceeds the limit," the real improvement in this step lies in transforming the early warning from a passive response to a proactive output. Traditional methods often assume that the system has no significant delay, or even if there is a delay, they do not handle it separately, resulting in early warning results that are always slightly lagging behind the actual risk. This embodiment no longer treats delay as a negligible error, but explicitly incorporates the delays of each stage of acquisition, communication, calculation, and output into the early warning model. At the same time, the alarm basis in traditional methods is usually still whether the current distance is less than a certain threshold, while this embodiment, after delay compensation, continues to generate risk assessment results for future moments based on normal velocity, attitude angle, and angular velocity. In this way, even if the current distance has not yet entered the danger zone, as long as the compensated future state shows that it will soon enter the danger zone, the system can output a higher-level early warning in advance.

[0041] For example, at a certain moment, the berthing / departure risk status set output by step S40 shows: normal distance of 12.41 meters, normal velocity of 0.17 meters per second, attitude angle of 2.8 degrees, and angular velocity of 0.39 degrees per second. At this time, the acquisition delay in the monitoring link is 38 milliseconds, the communication delay is 33 milliseconds, the calculation delay is 26 milliseconds, the output delay is 21 milliseconds, and the total delay is 118 milliseconds. In the traditional way, the system would only judge that the key alarm threshold has not yet been reached based on the current result of 12.41 meters. However, this embodiment first constructs the delay-compensated status result based on the above status variables, and then extrapolates the future risk assessment result 118 milliseconds in advance. After extrapolation, it can be found that the normal distance will further decrease, and the attitude angle still has an increasing trend. Therefore, the status that originally only corresponds to a normal warning will be upgraded to a level one warning. If, at another moment, the current normal distance has decreased to 8.35 meters, the normal velocity to 0.23 meters per second, the attitude angle to 4.2 degrees, and the total delay to 165 milliseconds, then the future risk assessment result after delay compensation may directly jump to the level two warning or even level three emergency warning range. Therefore, the value of this step lies not in dividing the alarm into several levels, but in making these levels earlier and closer to the actual direction of risk evolution.

[0042] Example 2: Furthermore, the present invention provides a laser synchronous monitoring system for ship berthing and unberthing safety angles and speeds, employing a laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in the above embodiments, which can solve the technical problem of laser synchronous monitoring of ship berthing and unberthing safety angles and speeds. The beneficial effects of the laser synchronous monitoring system for ship berthing and unberthing safety angles and speeds provided by the present invention are the same as those of the laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds provided in the above embodiments, and other technical features of the laser synchronous monitoring system for ship berthing and unberthing safety angles and speeds are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0043] Example 3: This invention provides a laser synchronous monitoring device for the safety angle and speed of ships berthing and unberthing. Please refer to... Figure 2A laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds includes: 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, which are executed by the at least one processor to enable the at least one processor to perform the laser-synchronized monitoring method for ship berthing and unberthing safety angles and speeds described in Embodiment 1 above. The laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds in this embodiment of the invention may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle terminals (e.g., vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. This laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds is merely an example and should not impose any limitations on the functionality and scope of use of this embodiment of the invention. A laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory 1002 or a program loaded from a storage device 1003 into a random access memory 1004. The random access memory 1004 also stores various programs and data required for the operation of the laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds. The processing unit 1001, the read-only memory 1002, and the random access memory 1004 are interconnected via a bus 1005. An I / O interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. Communication device 1009 allows a laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds to communicate wirelessly or via wired means with other devices to exchange data. While the figure shows a laser-synchronized monitoring device for ship berthing and unberthing safety angles and speeds with various systems, it should be understood that implementation of or possession of all the systems shown is not required. More or fewer systems may be implemented alternatively.

[0044] Example 4: This invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described above. The computer program product provided by this invention can solve the technical problem of laser synchronous monitoring of ship berthing and unberthing safety angles and speeds. Compared with the prior art, the beneficial effects of the computer program product provided by this invention are the same as those of the laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds provided in the above embodiments, and will not be repeated here.

[0045] In particular, according to the embodiments disclosed in this invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this invention include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from read-only memory 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this invention.

[0046] It should be understood that the various parts disclosed in this invention can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0047] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A laser-synchronized monitoring method for the safety angle and speed of ships berthing and unberthing, characterized in that, The methods include: Step S10: Obtain multi-source raw laser echo data, laser ranging unit installation parameters, and environmental parameters of the target vessel during the berthing or departure monitoring period. Combine the unified time reference reconstruction and candidate echo spatial mapping mechanism to perform the synchronous candidate echo set construction task and output the synchronous candidate echo set. Step S20: Based on the synchronous candidate echo set, a physical consistency feature construction task is performed using an environmental attenuation compensation and incident angle intensity consistency characterization mechanism, and a physical consistency feature set is output; Step S20 specifically includes: Step S201: Obtain visibility parameters, humidity parameters, wave height values, and wind and wave disturbance parameters, and construct equivalent environmental attenuation parameters for the current monitoring time based on the visibility parameters, humidity parameters, wave height values, and wind and wave disturbance parameters; Step S202: Input the synchronous candidate echo set into the preset local plane model of the hull side, and the local plane model of the hull side outputs the corresponding incident angle parameters; and construct the theoretical echo intensity estimate based on the equivalent environmental attenuation parameters, candidate echo ranging values ​​and incident angle parameters by using a coupled representation method of propagation attenuation term and angle reflection term. Step S203: Obtain the measured intensity values ​​of candidate echoes, and construct a physical consistency feature set based on the deviation between the measured intensity values ​​of candidate echoes and the theoretical echo intensity estimates; Step S202 specifically includes: The laser round-trip propagation path length is constructed based on the candidate echo ranging values, and the distance attenuation contribution is constructed based on the laser round-trip propagation path length. Construct the environmental loss contribution based on the equivalent environmental attenuation parameters; The angle reflection contribution between the laser incident direction and the normal of the local surface of the hull side is constructed based on the incident angle parameter. The angle reflection contribution is used to represent the degree of influence of the hull surface on the laser echo intensity. The distance attenuation contribution, environmental loss contribution, and angle reflection contribution are coupled together to obtain a theoretical echo intensity estimate. The theoretical echo intensity estimate is used to reflect the distance attenuation characteristics, environmental attenuation characteristics, and angle reflection characteristics of the candidate echo in the current strong reflection environment of the port water surface. Step S30: Based on the physical consistency feature set, perform the purification preprocessing task using temporal consistency constraints and a multi-candidate echo confidence screening mechanism, and output the purification distance observation set; Step S40: Execute the berthing and departure status monitoring task based on the purification distance observation set, and output the berthing and departure risk status set; Step S50: Perform delay compensation early warning processing and output the results based on the berthing and departure risk status set, and output the graded early warning results.

2. The laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in claim 1, characterized in that, Step S10 specifically includes: Step S101: Obtain the raw laser echo data output by multiple laser ranging units deployed at intervals along the berthing shoreline during the target monitoring period. The raw laser echo data includes at least candidate echo ranging values, candidate echo intensity values, and sampling timestamps. Also, obtain the installation position parameters and emission direction parameters of each laser ranging unit in the wharf reference coordinate system. Step S102: Based on the sampling timestamps of each laser ranging unit, perform fixed clock offset compensation and clock drift compensation on the original laser echo data to construct a synchronous echo sequence under a unified time reference; Step S103: Based on the synchronous echo sequence under a unified time reference and the installation position parameters and emission direction parameters of each laser ranging unit, the synchronous echo sequence is mapped to candidate spatial points under the dock reference coordinate system, and the synchronous candidate echo set is output.

3. The laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in claim 1, characterized in that, Step S30, based on the physical consistency feature set, employs a temporal consistency constraint and a multi-candidate echo confidence screening mechanism to perform the purification preprocessing task and output the purification distance observation set. Specifically, this includes: Step S301: Obtain the ship berthing and departure status results at historical moments, and construct the predicted distance result at the current monitoring moment using a long short-term memory network based on the ship berthing and departure status results at historical moments; obtain the current candidate echo ranging value, and construct a temporal consistency residual based on the difference between the current candidate echo ranging value and the predicted distance result; Step S302: Based on the physical consistency feature set and temporal consistency residual, calculate the true echo confidence score for multiple candidate echoes corresponding to each laser ranging unit; Step S303: The candidate echo whose true echo confidence score is greater than the preset confidence threshold and is the best among multiple candidate echoes in the corresponding laser ranging unit is determined as the true echo of the target, and the ranging value corresponding to the true echo of the target is constructed as a purification distance observation set.

4. The laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in claim 1, characterized in that, Step S40, which involves performing berthing / departure status monitoring based on the purification distance observation set and outputting a berthing / departure risk status set, specifically includes: Input the purification distance observation set into the preset state monitoring model, and jointly estimate the normal distance, normal velocity, attitude angle and angular velocity of the target ship at the current monitoring time to obtain the berthing and departure state results; Based on the berthing and departure status results, the berthing and departure movement trend of the target vessel relative to the dock reference line is calculated, and a risk assessment result is generated based on the berthing and departure movement trend. Based on the normal distance, normal velocity, attitude angle, angular velocity, and risk assessment results, a set of berthing and unberthing risk states is constructed.

5. The laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in claim 1, characterized in that, Step S50, which involves performing delay compensation early warning processing and outputting tiered early warning results based on the berthing and departure risk state set, specifically includes: Step S501: Obtain the acquisition delay, communication delay, calculation delay and output delay in the current monitoring link, and construct the delay compensation state result in combination with the berthing and departure risk state set; Step S502: Based on the delay compensation state results, use the state extrapolation prediction method to calculate the risk assessment results for future times, and generate graded early warning results based on the risk assessment results for future times; Step S503: Output the graded early warning result, which includes at least one of the following: normal monitoring status, first-level early warning status, second-level early warning status, and third-level emergency early warning status.

6. A laser synchronous monitoring system for ship berthing and unberthing safety angles and speeds, applied to the laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in any one of claims 1 to 5, characterized in that, The laser-synchronized monitoring system for ship berthing and unberthing safety angles and speeds includes: The synchronous candidate echo set construction module is used to acquire multi-source raw laser echo data, laser ranging unit installation parameters, and environmental parameters of the target vessel during the berthing or departure monitoring period. It combines the unified time reference reconstruction and candidate echo spatial mapping mechanism to perform the synchronous candidate echo set construction task and output the synchronous candidate echo set. The physical consistency feature construction module is used to perform the physical consistency feature construction task based on the synchronous candidate echo set, using an environmental attenuation compensation and incident angle intensity consistency characterization mechanism, and output a physical consistency feature set. The purification distance observation set construction module is used to perform purification preprocessing tasks based on the physical consistency feature set, using temporal consistency constraints and a multi-candidate echo confidence screening mechanism, and output the purification distance observation set. The berthing and unberthing status monitoring module is used to perform berthing and unberthing status monitoring tasks based on the purification distance observation set and output the berthing and unberthing risk status set; The graded early warning output module is used to perform delay compensation early warning processing and output the results based on the berthing and departure risk status set, and output graded early warning results.

7. A laser-synchronized monitoring device for the safe angle and speed of ships berthing and unberthing, characterized in that, The laser synchronous monitoring device for ship berthing and unberthing safety angles and speeds includes: a memory, a processor, and a laser synchronous monitoring program for ship berthing and unberthing safety angles and speeds stored in the memory and executable on the processor. When the laser synchronous monitoring program for ship berthing and unberthing safety angles and speeds is executed by the processor, it implements a laser synchronous monitoring method for ship berthing and unberthing safety angles and speeds as described in any one of claims 1 to 5.

8. A computer program product, characterized in that, The computer program product includes a laser synchronous monitoring program for the safe angle and speed of a ship berthing and unberthing. When the laser synchronous monitoring program for the safe angle and speed of a ship berthing and unberthing is executed by the processor, it implements a laser synchronous monitoring method for the safe angle and speed of a ship berthing and unberthing as described in any one of claims 1 to 5.

Images