A navigation method and system for real-time monitoring and early warning of port vehicles

Abstract

The present invention relates to the field of smart port technology, and in particular to a navigation method and system for real-time monitoring and early warning of port vehicles. The present invention solves the problem of how to solve the deviation between a preset scheduling plan and a real-time execution state caused by dynamic uncertainty of external container trucks in the port, thereby improving the dynamic adaptability of navigation. To solve the above problem, an embodiment of the present invention provides a navigation method, comprising: generating a preset route for the external container truck and a backup route for internal vehicles based on the reservation record of the external container truck and the scheduling plan of the port; when there is a deviation between the driving route and the preset route, predicting the theoretical time period for the external container truck to pass through each key node on the preset route; obtaining the driving flow of each key node on the path in each theoretical time period, updating the preset route according to the driving flow, and obtaining an updated route; and adjusting the backup route according to the traffic changes that subsequently affect the node.

Description

Technical Field

[0001] The present invention relates to the field of smart port technology, and in particular to a navigation method and system for real-time monitoring and early warning of port vehicles. Background Art

[0002] As a vital hub for global trade, ports handle the loading, unloading, transportation, and storage of large quantities of cargo. In daily port operations, container trucks frequently transport and load / unload cargo within the port, and the safety and efficiency of their operations directly impact the overall port operations.

[0003] Internal container trucks (internal container trucks) are terminal vehicles equipped with a GPS-based intelligent vehicle monitoring and dispatching system. They rely on the port's pre-set high-precision maps and real-time sensor network to operate. While external container trucks (external container trucks) can receive assigned tasks from the port, they face challenges in operating within the port. Dynamic changes in factors such as the actual arrival time of external container trucks, real-time traffic conditions within the port, and operating hours can make it difficult for external container trucks to fully adhere to the navigation routes and time windows of the pre-set scheduling plan. This can lead to mismatches between the pre-set scheduling plan and real-time operating status, which in turn affects the efficiency of port resource scheduling and the dynamic adaptability of the navigation system.

[0004] With the actual needs of safe production in port areas, traditional port vehicle monitoring and navigation methods can no longer meet the needs of efficient and safe port operations. Therefore, there is an urgent need for a navigation method and system that can reasonably optimize navigation routes based on real-time dynamic data and scheduling strategies. Summary of the Invention

[0005] The problem solved by the present invention is how to solve the deviation between the preset scheduling plan and the real-time execution status caused by the dynamic uncertainty of container trucks outside the port, thereby improving the dynamic adaptability of navigation.

[0006] To solve the above problems, an embodiment of the present invention provides a navigation method for real-time monitoring and early warning of port vehicles, the navigation method comprising: generating a preset route for external container trucks and a backup route for internal vehicles based on the reservation records of the external container trucks and the port's scheduling plan; adjusting the preset route based on the actual arrival time and real-time traffic flow data; when there is a deviation between the driving route and the preset route, predicting the theoretical time period for the external container trucks to pass through each key node on the preset route; obtaining the driving flow at each key node in each theoretical time period, updating the preset route based on the driving flow, and obtaining an updated route; when the updated route reaches the target execution progress, obtaining the subsequent influencing nodes of the updated route, and adjusting the backup route based on the traffic changes at the subsequent influencing nodes.

[0007] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: the determination of preset routes and reserve routes fully considers the reservation records and scheduling plans, which helps the port to grasp the needs of internal and external vehicles in advance, and balance the operation processes of internal and external vehicles according to specific needs, avoid waste of resources, and improve overall operation efficiency. The preset routes can be dynamically optimized by combining real-time traffic flow data with actual arrival time, avoid real-time traffic risks, reduce travel delays, and effectively reduce the system calculation complexity by focusing on key nodes of the path instead of full route tracking, and improve the response speed of real-time monitoring and early warning. The calculation of the theoretical time period fully considers the driving route and the preset route. The real-time deviation of the route and the traffic characteristics of key nodes are set to help convert route deviation into quantifiable time parameters. The traffic flow quantifies the traffic pressure at key nodes of each path, providing data support for route adjustments. Updating the route helps ensure that container trucks always follow the optimal route, improving driving and operating efficiency. The target execution progress is the key node for determining whether to initiate the adjustment of the reserve route, which can effectively avoid ineffective scheduling. By identifying and monitoring the traffic changes that will subsequently affect the nodes in advance, potential traffic risks can be effectively predicted and the reserve route can be adjusted in time, significantly improving the efficiency, stability and risk resistance of port operations.

[0008] In one embodiment of the present invention, the preset route is adjusted according to the actual arrival time and real-time traffic flow data, specifically including: obtaining the theoretical traffic flow at the scheduled arrival time according to the reservation record, comparing the theoretical traffic flow with the actual traffic flow at the actual arrival time, and obtaining the traffic flow difference; when the traffic flow difference is greater than the traffic flow threshold, obtaining the stage destination of the external container truck vehicle, and obtaining the optional path to the stage destination; obtaining the optional nodes in each optional path, calculating the corrected time period for the external container truck vehicle to pass through each optional node, and selecting an optional route to replace the preset route according to the corrected time period; if the traffic flow difference is less than or equal to the traffic flow threshold, the scheduled route does not need to be adjusted.

[0009] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the determination of the scheduled arrival time helps to plan resource allocation in advance, avoiding entrance congestion caused by multiple vehicles arriving at the port at the same time; calculating the traffic flow difference by theoretical traffic flow and actual traffic flow helps to dynamically adjust the preset route based on real-time traffic flow data, ensuring that route planning adapts to the actual traffic operation status; based on the comparison of the traffic flow difference with the traffic flow threshold, it ensures that adjustments are triggered only when there is a significant change in traffic flow, reducing invalid computing resource consumption; focusing on the stage destination can effectively avoid the computational redundancy of global re-planning, improve the response speed of the navigation system, and screen the optional routes by comparing multiple optional paths, avoiding the scheduling rigidity caused by "single route dependence" and improving the flexibility and adaptability of navigation.

[0010] In one embodiment of the present invention, the optional nodes in each optional path are obtained, the corrected time period for the external container truck to pass through each optional node is calculated, and the optional route to replace the preset route is selected according to the corrected time period, specifically including: obtaining the road traffic conditions of the optional nodes in each corrected time period; calculating the unit impact time caused by the external container truck passing through the optional node according to the road traffic conditions; calculating the total impact time corresponding to each optional path according to the unit impact time, and determining the optional route to replace the preset route according to the total impact time and the driving distance.

[0011] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the calculation of the corrected time period fully considers the real-time traffic flow data, which helps to accurately estimate the time range for external container trucks to arrive at the optional nodes. The road traffic conditions fully reflect the actual traffic pressure of the optional nodes within the corrected time period, providing accurate data for the calculation of the unit impact time. The unit impact time converts the complex traffic status into a quantifiable time cost, which facilitates the navigation system to make a horizontal comparison of the traffic efficiency of different optional nodes, and provides an intuitive time dimension indicator for the determination of optional routes. By comprehensively considering the total impact time and driving distance of each optional path, the navigation system can find a balance between efficiency and energy consumption, give priority to routes with the lowest time cost and reasonable distance, and avoid decision-making deviations caused by a single indicator.

[0012] In one embodiment of the present invention, when a driving route deviates from a preset route, a theoretical time period for an external container truck to pass through each key node on the preset route is predicted, specifically including: determining the execution route of the external container truck after the deviation occurs based on the deviation section and stage destination; obtaining vehicle data of the external container truck, and determining the start-stop rate and average driving speed of the external container truck based on the vehicle data; and calculating the theoretical time period based on the start-stop rate and the average driving speed.

[0013] Compared with the existing technology, the technical effects achieved by adopting this technical solution are: by locating the deviation sections, the system can quickly identify the key path nodes that need to be recalculated, avoiding redundant calculations for replanning the entire route; the generation of the execution route takes into account the stage destination, ensuring that the external container truck vehicle can still reach the stage destination after deviating from the original route; the start-stop rate quantifies the acceleration and deceleration time of the external container truck vehicle, fully considering the impact of the start-stop process on the driving time; the average driving speed calculated based on the personalized data of the external container truck vehicle avoids the "one-size-fits-all" speed assumption, helps to accurately quantify the driving time based on the dynamic characteristics of the vehicle, and improves the prediction accuracy of the subsequent theoretical time period.

[0014] In one embodiment of the present invention, the driving flow of each key node of the path in each theoretical time period is obtained, and the preset route is updated according to the driving flow to obtain an updated route, specifically including: obtaining the expected flow of external container trucks passing through each key node of the path according to the preset route; comparing the expected flow with the driving flow to obtain the node to be replaced of the preset route; selecting a replacement method for the node to be replaced according to the connection path between the node to be replaced and the subsequent key node of the path; and updating the preset route according to the replacement method to obtain an updated route.

[0015] Compared with the existing technology, the technical effects achieved by adopting this technical solution are: the prediction of expected traffic provides benchmark data for subsequent real-time comparison; by comparing the expected traffic and the driving traffic, the nodes to be replaced where the traffic efficiency is reduced due to abnormal traffic can be accurately located; and by focusing on the locally inefficient nodes to be replaced, redundant calculations for re-planning the entire route are avoided, thereby improving the response speed and efficiency of the navigation system; the connection path fully considers the continuity between the node to be replaced and the key nodes of the subsequent path, avoiding route breaks or detouring to inaccessible areas; and selecting a reasonable replacement method based on the connection characteristics of the node to be replaced and the key nodes of the subsequent path can effectively improve traffic efficiency, thereby achieving "precise optimization and minimum cost" route updates.

[0016] In one embodiment of the present invention, the expected traffic flow is compared with the driving traffic flow to obtain the node to be replaced on the preset route, specifically including: calculating the unit delay time of passing the key node of the path based on the expected traffic flow and the driving traffic flow, and calculating the total delay time of maintaining the preset route based on the unit delay time; obtaining the congestion coefficient corresponding to the theoretical time period based on real-time traffic flow data, and determining whether the key node of the path is the node to be replaced based on the total delay time and the congestion coefficient.

[0017] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the unit delay time converts the traffic flow difference into a calculable time cost, providing a quantitative basis for the replacement decision of the key nodes of the path; the total delay time reflects the correlation influence between the key nodes of each path; by accumulating the unit delay time of the current node and its upstream key nodes, the transmission and amplification effect of the upstream delay on the downstream is quantified, avoiding focusing only on the optimization of a single key node of the path while ignoring the chain reaction of the entire route, providing a basis for systematic route adjustment; the congestion coefficient refines the impact of traffic flow differences on traffic, avoiding relying solely on traffic flow to judge congestion, thereby improving the accuracy of the judgment of the node to be replaced.

[0018] In one embodiment of the present invention, when the updated route reaches the target execution progress, the subsequent impact node of the updated route is obtained, and the preliminary route is adjusted according to the traffic changes of the subsequent impact node, specifically including: calculating the time impact range of the subsequent impact node due to the updated route; obtaining the target time for the internal vehicle to arrive at the subsequent impact node according to the preliminary route; when the target time is within the time impact range, adjusting the preliminary route according to the task type of the internal vehicle and the idle time period of the subsequent impact node; when the target time is outside the time impact range, the preliminary route does not need to be adjusted before driving to the subsequent impact node.

[0019] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the calculation of the time impact range helps to identify the congestion periods that will affect the nodes in advance, avoiding the passive response of the navigation system and the blind adjustment of the reserve routes. The target time clarifies the conflict time between internal vehicles and external container trucks. The target time and the time impact range can be used to effectively determine whether the reserve route needs to be adjusted. The reserve route can be adjusted according to the task type and idle time period, which helps to prioritize the completion of high-priority tasks on time and improve the overall scheduling efficiency and navigation flexibility.

[0020] In one embodiment of the present invention, when the target moment is within the time influence range, the backup route is adjusted according to the task type of the internal vehicle and the idle time period of the subsequent impact node, specifically including: when the time difference between the idle time period and the target moment is less than or equal to the time threshold, reducing the comprehensive average speed of the internal vehicle, and controlling the internal vehicle to pass through the subsequent impact node within the idle time period; when the time difference between the idle time period and the target moment is greater than the time threshold, determining the adjustment method of the comprehensive average speed according to the priority of the task type.

[0021] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: using the time difference between the target time and the idle time period as the adjustment trigger condition, and implementing a differentiated adjustment strategy for the comprehensive average speed in combination with the task type, it can ensure the execution priority of each task type while efficiently utilizing the idle resources of the node, thereby realizing dynamic optimization of the preparation route.

[0022] In one embodiment of the present invention, in one embodiment of the present invention, a navigation system for real-time monitoring and early warning of port vehicles is also provided. The navigation method recorded in the above embodiment is applied to the navigation system, and the navigation system includes: a map module, the map module is used to generate preset routes and backup routes based on the reservation records of external container trucks and the port's scheduling plan; an adjustment module, the adjustment module is used to adjust the preset route according to the actual arrival time and real-time traffic flow data; a prediction module, the prediction module is used to predict the theoretical time period; and an update module, the update module is used to update the preset route. The navigation system has all the technical features of the above navigation method, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 One of the flowcharts of the navigation method;

[0024] Figure 2 This is the second flowchart of the navigation method;

[0025] Figure 3 This is the third flowchart of the navigation method;

[0026] Figure 4 This is the fourth flowchart of the navigation method;

[0027] Figure 5 This is the fifth flowchart of the navigation method;

[0028] Figure 6 is a system diagram of the navigation system;

[0029] Description of reference numerals:

[0030] 100 - Navigation system; 110 - Map module; 120 - Adjustment module; 130 - Prediction module; 140 - Update module. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0032] [First embodiment]

[0033] See also Figure 1 In a specific embodiment, the present invention provides a navigation method for real-time monitoring and early warning of port vehicles, the navigation method comprising:

[0034] S100: Generate a preset route for the external container truck and a prepared route for the internal vehicle based on the reservation record of the external container truck and the port's dispatch plan;

[0035] S200, adjusting the preset route according to the actual arrival time and real-time traffic flow data;

[0036] S300, when there is a deviation between the driving route and the preset route, predicting the theoretical time period for the external container truck to pass through each key node on the preset route;

[0037] S400, obtaining the driving flow of each key node of the path in each theoretical time period, and updating the preset route according to the driving flow to obtain an updated route;

[0038] S500: When the updated route reaches the target execution progress, the subsequent impact nodes of the updated route are obtained, and the backup route is adjusted according to the traffic changes of the subsequent impact nodes.

[0039] In step S100 and step S200, the reservation record refers to the reservation information submitted by the external container truck before performing port operations, including the scheduled arrival time, transportation tasks and basic vehicle information, etc. The scheduling plan refers to the resource allocation plan formulated within the port, including the allocation and time arrangement of resources such as internal container trucks, loading and unloading equipment and warehouse cargo space, etc. The preset route is the optimal route from the port entrance to the target operation point pre-planned for the external container truck based on the reservation record and the scheduling plan, and the backup route is the optimal operation route pre-planned for the internal container truck based on the reservation record and the scheduling plan. The actual arrival time refers to the specific time when the external container truck actually arrives at the port entrance. The real-time traffic flow data refers to the traffic data of the internal roads of the port at the actual arrival time, usually including real-time traffic volume, average speed and congestion status information.

[0040] It should be noted that external container trucks receive tasks through the port's dedicated APP and make reservations before entering the port so that the port scheduling system can reserve corresponding resources and generate preset routes and backup routes. When external container trucks follow the preset routes and internal container trucks follow the backup routes, the scheduling plan for the day is theoretically in the optimal resource matching state and the highest operating efficiency. However, the actual arrival time may deviate from the scheduled arrival time due to factors such as traffic congestion or weather, resulting in the original route no longer having the traffic efficiency advantage due to real-time traffic flow changes. At this time, the preset route needs to be corrected through a subsequent dynamic adjustment mechanism to ensure that the coordination of the internal and external container truck operation processes is not affected by actual deviations.

[0041] In step S300 and step S400, the driving route refers to the real-time navigation route followed by the external container truck during its actual driving in the port, the key node of the path refers to the key location points in the preset route that have a greater impact on the traffic efficiency, such as intersections and entrances and exits of loading and unloading areas, the theoretical time period refers to the specific time interval during which the external container truck is expected to pass through subsequent key nodes in the preset route when the driving route deviates from the preset route, the driving flow refers to the actual traffic flow at each key node of the path in each theoretical time period, and the updated route refers to the new navigation route generated after adjusting the preset route according to the driving flow.

[0042] In step S500, the target execution progress refers to the staged completion standards that need to be achieved for the updated route. The subsequent impact nodes refer to the key nodes that are directly or indirectly affected by the change in the driving route in the subsequent driving path of the target execution progress after the external container truck vehicle travels according to the updated route. The traffic change situation refers to the changes in traffic parameters such as traffic flow, travel speed and queue length at the subsequent impact nodes after the updated route is executed.

[0043] It should be noted that subsequent impact nodes are key nodes on the downstream path that may cause chain congestion or efficiency fluctuations after the execution of the updated route. They usually include the intersection nodes of the updated route and the preset route in the subsequent path, as well as the key nodes on the path adjacent to the updated route.

[0044] For example, when the adjusted preset route is the port's east entrance - X1 main road - X2 main road - Y1 loading and unloading area, and the driving route is the port's east entrance - X2 main road - X3 main road - Y1 loading and unloading area, real-time monitoring shows that the traffic volume on X3 main road is high during the theoretical time period, which will cause congestion for external container trucks. Therefore, the updated route is the port's east entrance - X2 main road - X4 main road - Y1 loading and unloading area. The target execution progress is to pass through the key node Z2 of the path connecting X2 main road and X4 main road. When the updated route is executed to the key node Z2 of the path, it means that the target execution progress has been achieved, and the subsequent impact nodes of the updated route can be obtained.

[0045] The determination of preset and backup routes fully considers reservation records and scheduling plans, helping ports to proactively understand internal and external vehicle needs and balance their operational processes based on specific needs, avoiding resource waste and improving overall operational efficiency. Real-time traffic flow data and actual arrival times enable dynamic optimization of preset routes, mitigating real-time traffic risks and reducing travel delays. By focusing on key nodes instead of full route tracking, the system effectively reduces computational complexity and improves the response speed of real-time monitoring and early warning. The calculation of theoretical time periods fully considers the real-time deviation between the route and the preset route and the traffic characteristics of key nodes, helping to convert route deviations into quantifiable time parameters. Traffic flow quantifies the traffic pressure at key nodes on each route, providing data support for route adjustments. Route updates help ensure that external container trucks always follow the optimal route, improving travel and operational efficiency. Target execution progress, as the key node for determining whether to initiate backup route adjustments, effectively avoids ineffective scheduling. By proactively identifying and monitoring traffic changes at subsequent impacting nodes, potential traffic risks can be effectively predicted and backup routes adjusted in a timely manner, significantly improving the efficiency, stability, and risk resilience of port operations.

[0046] [Second embodiment]

[0047] See also Figure 2 In a specific embodiment, adjusting the preset route based on the actual arrival time and real-time traffic flow data specifically includes:

[0048] S210: Obtain theoretical traffic flow at the scheduled arrival time based on the reservation record, compare the theoretical traffic flow with the actual traffic flow at the actual arrival time, and obtain a traffic flow difference;

[0049] S220: When the traffic flow difference is greater than the traffic flow threshold, the stage destination of the external container truck is obtained, and an optional path to the stage destination is obtained;

[0050] S230, obtaining the optional nodes in each optional path, calculating the modified time period for the container truck to pass through each optional node, and selecting an optional route to replace the preset route based on the modified time period;

[0051] S240: If the traffic flow difference is less than or equal to the traffic flow threshold, the reserved route does not need to be adjusted.

[0052] In steps S210 and S220, the scheduled arrival time refers to the specific time at which the external container truck is scheduled to arrive at the port entrance as submitted through the reservation record, which usually includes precise time information such as date, hour and minute. The theoretical traffic volume refers to the planned traffic volume on the preset route within the port at the scheduled arrival time. The actual traffic volume refers to the real-time traffic volume on the preset route within the port at the actual arrival time. The traffic volume difference refers to the absolute value of the difference between the theoretical traffic volume and the actual traffic volume. The traffic volume threshold refers to the average traffic volume of the preset route under historical congestion conditions. The congestion state refers to the traffic operation state in which the actual traffic volume on the preset route exceeds the critical threshold of its designed traffic capacity and is accompanied by a significant decrease in traffic efficiency. The stage destination refers to the current target position of the external container truck in the port, such as the temporary parking area and the entrance to the loading and unloading area. The optional path refers to multiple drivable routes from the port entrance where the external container truck is located to the stage destination.

[0053] In step S230 and step S240, the optional node refers to the key position in the optional path that has a greater impact on the traffic efficiency, such as an intersection and a fork in the road. The corrected time period refers to the estimated time interval for the external container truck to travel from the current position to pass through the optional node calculated in combination with real-time traffic flow data. The optional route refers to the optimal alternative route to the preset route selected by the corrected time period.

[0054] It should be noted that the port navigation system pre-builds a library of optional nodes for the port based on the road network structure and historical traffic data of the port's electronic map, and marks nodes that affect traffic efficiency, such as intersections, confluence points or bottleneck section entrances connecting branch sections in the path, as optional nodes. When generating an optional path, the navigation system automatically filters out nodes in the optional node library from the path as optional nodes, and determines the correction time period based on the average speed of external container trucks and the traffic flow, signal light cycle, speed limit and other data of each optional node.

[0055] For example, when the optional node is the auxiliary road entrance N1, there are 3 vehicles queued in front of the external container truck, the current time is 10:00:00, the real-time traffic flow of the auxiliary road entrance N1 is 6 vehicles / minute, the signal light cycle is 60s, of which the green light duration is 30s, the average driving speed of the external container truck is 20km / h, and the length of the auxiliary road entrance N1 is 111m. Then, the maximum waiting time of the external container truck is 90s, and the passing time is 20s. The corrected time period is 10:00:00~10:01:50.

[0056] Determining the scheduled arrival time helps to plan resource allocation in advance and avoid entrance congestion caused by multiple vehicles arriving at the port at the same time. Calculating the traffic flow difference between theoretical and actual traffic flow helps to dynamically adjust the preset route based on real-time traffic flow data, ensuring that route planning adapts to actual traffic operation conditions. By comparing the traffic flow difference with the traffic flow threshold, adjustments are only triggered when there is a significant change in traffic flow, reducing ineffective computing resource consumption. Focusing on the stage destination can effectively avoid computational redundancy in global re-planning and improve the response speed of the navigation system. By comparing multiple optional paths and screening optional routes, scheduling rigidity caused by "single route reliance" is avoided, thereby improving the flexibility and adaptability of navigation.

[0057] [Third embodiment]

[0058] See also Figure 2 In a specific embodiment, the optional nodes in each optional path are obtained, the modified time period for the truck to pass through each optional node is calculated, and the optional route to replace the preset route is selected based on the modified time period, specifically including:

[0059] S231. Obtaining road traffic conditions at selectable nodes within each correction time period;

[0060] S232. Calculate the unit impact duration caused by the passage of the external container truck through the optional node based on the road traffic conditions;

[0061] S233: Calculate the total impact duration corresponding to each optional route based on the unit impact duration, and determine an optional route that replaces the preset route based on the total impact duration and the driving distance.

[0062] In step S231 and step S233, the road traffic condition refers to the real-time traffic operation status of the optional nodes within the correction time period, which usually includes traffic volume, traffic speed and queue length, etc. The unit impact time refers to the additional waiting or deceleration time caused by poor road traffic conditions when the external container truck passes through a single optional node. The total impact time refers to the sum of the unit impact times of all optional nodes in each optional path, and the driving distance refers to the actual physical length of the optional path.

[0063] It should be noted that foreign container trucks entering from other entrances of the port area may also pass through the optional nodes during the correction time period, causing the actual traffic volume at the node to be higher than the predicted value of a single entrance, and even causing regional congestion. Therefore, it is necessary to integrate the reservation records of multiple entrances, real-time positioning data, and traffic flow information collected by sensors through the port dispatching system to comprehensively calculate the global traffic conditions of the optional nodes during the correction time period.

[0064] For example, when the optional node is auxiliary road entrance N1, it is originally expected that there will be 3 vehicles queuing in front of the external container truck, and the maximum waiting time will be 90 seconds. However, 5 additional external container trucks entering from other entrances will enter the current road section within the corrected time period and queue up to enter auxiliary road entrance N1. In this case, the number of vehicles queuing in front of the external container truck will become 8. When the current time when the external container trucks start queuing is 10:00:00, the real-time traffic flow at auxiliary road entrance N1 is 6 vehicles / minute, the signal light cycle is 60 seconds, of which the green light duration is 30 seconds, the average speed of external container trucks is 20 km / h, and the length of auxiliary road entrance N1 is 111 meters. In this case, the maximum waiting time for the external container trucks is 170 seconds, and the passing time is 20 seconds. The unit impact time is the additional waiting time caused by the 5 additional external container trucks, which is 80 seconds.

[0065] The calculation of the corrected time period fully considers real-time traffic flow data, which helps to accurately estimate the time range for external container trucks to arrive at optional nodes. The road traffic conditions fully reflect the actual traffic pressure of the optional nodes within the corrected time period, providing accurate data for the calculation of unit impact time. The unit impact time converts complex traffic conditions into quantifiable time costs, which facilitates the navigation system to conduct horizontal comparisons of the traffic efficiency of different optional nodes and provides an intuitive time dimension indicator for the determination of optional routes. By comprehensively considering the total impact time and driving distance of each optional path, the navigation system can find a balance between efficiency and energy consumption, giving priority to routes with the lowest time cost and reasonable distance, and avoiding decision-making bias caused by a single indicator.

[0066] [Fourth embodiment]

[0067] See also Figure 3 In a specific embodiment, when the driving route deviates from the preset route, the theoretical time period for the truck to pass through each key node on the preset route is predicted, specifically including:

[0068] S310, determining the execution route of the external container truck after the deviation occurs according to the deviation section and the stage destination;

[0069] S320: Acquire vehicle data of the external container truck, and determine the start / stop rate and average travel speed of the external container truck based on the vehicle data;

[0070] S330: Calculate a theoretical time period based on the start-stop rate and the average driving speed.

[0071] In steps S310 to S330, the deviation section refers to the specific section where the actual driving route of the external container truck is different from the adjusted preset route. The execution route refers to the temporary driving path re-planned by the navigation system based on the stage destination and real-time road conditions after the deviation occurs. The vehicle data refers to the physical characteristics and operating capacity parameters of the external container truck, including load tonnage, body length, engine power and braking performance. The start-stop rate refers to the acceleration when the external container truck starts and the deceleration when it stops. The average driving speed refers to the average speed of the external container truck in the non-start-stop state, which is usually affected by factors such as road conditions, load and speed limit.

[0072] It should be noted that temporary construction, sudden accidents or driver errors in the port area will cause dynamic changes in the road, causing the external container truck to deviate from the preset route. When deviation occurs, the navigation system will generally dynamically generate an execution route based on the real-time position of the deviated section, the stage destination and the subsequent sections of the preset route that have not yet been traveled. The execution route is usually based on the principle of "shortest detour", that is, a feasible path that can quickly return to the subsequent key nodes of the preset route is selected to ensure that the vehicle continues to travel in the original planned direction after correcting the deviation. Since the execution route may include new sections for temporary detours, the theoretical time period for the external container truck to pass through the key nodes of each path on the preset route will change accordingly. At this time, the theoretical time period for the external container truck to pass through the key nodes of each path needs to be recalculated.

[0073] For example, when the time when the external truck deviates from the route is 11:00:00, the distance between the entrance of the deviated section and the nearest key node of the target path is 0.6km, and the start-stop rate is 0.5m / s 2 , the number of starts and stops is 1, and the average driving speed is 20km / h. It is calculated that the time it takes for the external container truck to reach the key node of the target path is the sum of the driving time and the start-stop time, which is 131s. The specific arrival time is 11:02:11. When driving according to the preset route, the theoretical time period for the external container truck to pass the key node of the target path is 11:01:00~11:01:20, that is, it takes 20s to pass the key node of the target path. According to the specific arrival time and the time it takes to pass the key node of the target path, the theoretical time period after deviating from the route is 11:02:11~11:02:31.

[0074] By locating deviation sections, the system can quickly identify key path nodes that need to be recalculated, avoiding redundant calculations for replanning the entire route. The generation of the execution route takes into account the stage destination, ensuring that the external container truck can still reach the stage destination after deviating from the original route. The start-stop rate quantifies the acceleration and deceleration time of the external container truck, fully considering the impact of the start-stop process on driving time. The average driving speed calculated based on the personalized data of the external container truck avoids the "one-size-fits-all" speed assumption, helps to accurately quantify the driving time based on the dynamic characteristics of the vehicle, and improves the prediction accuracy of the subsequent theoretical time period.

[0075] [Fifth embodiment]

[0076] See also Figure 4 In a specific embodiment, the traffic flow of each key node on the path is obtained in each theoretical time period, and the preset route is updated according to the traffic flow to obtain the updated route, which specifically includes:

[0077] S410: Obtaining the estimated flow of external container trucks passing through key nodes of each route according to the preset route;

[0078] S420: Compare the expected traffic flow with the driving traffic flow to obtain a node to be replaced on the preset route;

[0079] S430, selecting a replacement method for the node to be replaced based on a connection path between the node to be replaced and a subsequent key node on the path;

[0080] S440: Update the preset route according to the replacement method to obtain an updated route.

[0081] In step S410 and step S420, the expected traffic flow refers to the expected traffic flow at each key node of the path within each theoretical time period when the external container truck passes through each key node of the path according to the preset route. The driving traffic flow refers to the expected traffic flow at each key node of the path within each newly generated theoretical time period after deviating from the route. The node to be replaced refers to the key node of the path that needs to be replaced from the preset route because the driving traffic flow does not match the expected traffic flow, resulting in a significant decrease in traffic efficiency.

[0082] In step S430 and step S440, the connection path refers to the feasible connection route between the node to be replaced and the subsequent key node in the preset route. The replacement method refers to the adjustment strategy for the replacement node, such as selecting a new alternative node and optimizing the driving flow of the replacement node. Specific replacement methods include detour, diversion, speed adjustment and changing traffic signals.

[0083] It should be noted that the choice of replacement method must be based on the actual traffic capacity of the connecting path, ensuring that the updated route can not only avoid congestion or inefficiency problems at the nodes to be replaced, but also smoothly connect with the key nodes of the subsequent path to form a complete and efficient new route.

[0084] The forecast of expected traffic provides benchmark data for subsequent real-time comparison. By comparing the expected traffic and the driving traffic, the nodes to be replaced where the traffic efficiency has decreased due to abnormal traffic can be accurately located. By focusing on the locally inefficient nodes to be replaced, redundant calculations for re-planning the entire route are avoided, and the response speed and efficiency of the navigation system are improved. The connection path fully considers the continuity between the node to be replaced and the key nodes of the subsequent path to avoid route breaks or detours to inaccessible areas. Based on the connection characteristics of the node to be replaced and the key nodes of the subsequent path, a reasonable replacement method is selected, which can effectively improve traffic efficiency and thus achieve "precise optimization and minimum cost" route updates.

[0085] [Sixth embodiment]

[0086] See also Figure 4 In a specific embodiment, the predicted traffic volume is compared with the driving traffic volume to obtain the node to be replaced on the preset route, specifically including:

[0087] S421: Calculate the unit delay time of passing through key nodes of the route based on the expected traffic volume and the driving volume, and calculate the total delay time of maintaining the preset route based on the unit delay time;

[0088] S422. Obtain a congestion coefficient corresponding to a theoretical time period based on real-time traffic flow data, and determine whether a key node on the path is a node to be replaced based on the total delay time and the congestion coefficient.

[0089] In steps S421 and S422, the unit delay time refers to the additional time added when the external container truck passes through a single key node of the path due to the difference between the driving flow and the expected flow. The total delay time refers to the cumulative delay time caused by the external container truck while maintaining the preset route due to congestion or flow limit excess at multiple nodes to be replaced. The total delay time of the current node to be replaced is the sum of the unit delay times of the current node to be replaced and all upstream nodes to be replaced. The congestion coefficient refers to the congestion degree index of each key node of the path in a theoretical time period calculated based on real-time traffic flow data. The calculation formula of the congestion coefficient kc is:

[0090] kc=α×(fr÷ft)+β×(1-vr÷vt)+γ×(dr÷dt).

[0091] Among them, fr is the driving flow rate of the key node of the path, ft is the flow threshold of the key node of the path, vr is the average driving speed of the external container trucks passing the key node of the path, vt is the benchmark driving speed of the key node of the path when the traffic is smooth, vt is usually calculated based on historical data, dr is the real-time queue length of the external container trucks in front of the key node of the path, dt is the maximum queue length of the key node of the path when the traffic is smooth, α, β and γ are the weight coefficients of each indicator, satisfying α + β + γ = 1, usually α>β>γ, and when kc ≥ 0.8, the key node of the path is marked.

[0092] For example, a container truck passes through path critical node A between 10:00:00 and 10:00:20 and passes through path critical node B between 10:10:00 and 10:10:20 according to the preset route. However, due to route deviation, the theoretical time period for the container truck to pass through path critical node A changes to 10:02:00-10:02:20, and it passes through path critical node B between 10:13:00 and 10:13:20. In addition, there are differences in the driving volume and expected volume at path critical nodes A and B during the new theoretical time period. If the unit delay time of the container truck passing through path critical node A is 30s and the total delay time is 50s, and the unit delay time of passing through path critical node B is 20s, then the total delay time of passing through path critical node B can be calculated to be 70s. When the congestion coefficients of path critical nodes A and B both exceed 0.8, it is determined that path critical nodes A and B are both nodes to be replaced.

[0093] The unit delay time converts traffic flow differences into calculable time costs, providing a quantitative basis for replacement decisions of key nodes on the path. The total delay time reflects the correlation influence between key nodes on each path. By accumulating the unit delay time of the current node and its upstream key nodes, the transmission and amplification effect of upstream delays on downstream is quantified, avoiding focusing only on the optimization of a single key node on the path while ignoring the chain reaction of the entire route, providing a basis for systematic route adjustments. The congestion coefficient refines the impact of traffic flow differences on traffic flow, avoiding relying solely on traffic flow to judge congestion, thereby improving the accuracy of the judgment of nodes to be replaced.

[0094] [Seventh embodiment]

[0095] See also Figure 5 In a specific embodiment, when the updated route reaches the target execution progress, the subsequent impact nodes of the updated route are obtained, and the backup route is adjusted according to the traffic changes of the subsequent impact nodes, which specifically includes:

[0096] S510, calculating the time impact range of subsequent impact nodes due to the updated route;

[0097] S520: Obtain the target time for the internal vehicle to arrive at the subsequent impact node based on the prepared route;

[0098] S530: When the target time is within the time influence range, adjust the backup route according to the task type of the internal vehicle and the idle time period of the subsequent impact node;

[0099] S540: When the target time is outside the time influence range, the backup route does not need to be adjusted before traveling to the subsequent influence node.

[0100] In steps S510 to S540, the time impact range refers to the travel time fluctuation range of subsequent impact nodes caused by the updated route after the updated route is implemented. The target time refers to the time when the internal vehicles in the preparation route arrive at the subsequent impact nodes as originally planned, usually refers to the arrival time when the internal vehicles do not pass the subsequent impact nodes. The task type refers to the type of task performed by the internal vehicles, such as emergency delivery or ordinary delivery. The idle time period refers to the time window in which the subsequent impact nodes are not occupied and can pass smoothly within the time impact range.

[0101] It should be noted that when the target time is outside the time influence range, it means that the internal vehicles and external container trucks do not conflict in the travel time at the subsequent impact nodes, and there is no need to adjust the backup route. When the target time is within the time influence range, it means that the internal vehicles and external container trucks may conflict in the travel time at the subsequent impact nodes, and the backup route needs to be dynamically adjusted in combination with the task type priority and the node idle time period.

[0102] The calculation of the time impact range helps to identify the congestion periods that will subsequently affect the nodes in advance, avoiding the passive response of the navigation system and the blind adjustment of the alternative routes. The target time clearly defines the conflict time between internal vehicles and external container trucks. The target time and the time impact range can be used to effectively determine whether the alternative route needs to be adjusted. Adjusting the alternative route based on task type and idle time period helps to prioritize the timely completion of high-priority tasks and improve overall scheduling efficiency and navigation flexibility.

[0103] [Eighth embodiment]

[0104] See also Figure 5 In a specific embodiment, when the target time is within the time influence range, the backup route is adjusted according to the task type of the internal vehicle and the idle time period of the subsequent impact node, specifically including:

[0105] S531. When the time difference between the idle time period and the target time is less than or equal to the time threshold, reduce the comprehensive average speed of the internal vehicles and control the internal vehicles to pass through the subsequent impact nodes during the idle time period;

[0106] S532: When the time difference between the idle time period and the target time is greater than the time threshold, determine an adjustment method for the comprehensive average speed according to the priority of the task type.

[0107] In step S531 and step S532, the time difference refers to the absolute value of the time interval between the target time and the start time of the idle time period. The time threshold refers to the acceptable time deviation critical value preset by the navigation system based on the idle time period, which usually does not exceed the duration of the idle time period. The comprehensive average speed refers to the average driving speed of the internal vehicle on the preparation route. When calculating the comprehensive average speed, the time loss of acceleration, deceleration, parking and waiting processes must be considered. The adjustment method is a specific adjustment strategy for the comprehensive average speed determined based on the time difference and the task type.

[0108] For example, when the time range of the updated route's impact on the subsequent impact node C is 11:10:00~11:20:00, and the idle time period is 11:17:20~11:20:00, if the internal vehicle's target time is 11:15:30, then the time difference between the target time and the start time of the idle time period is less than the time threshold. By reducing the comprehensive average speed of the internal vehicle and extending the internal vehicle's travel time, the internal vehicle passes the subsequent impact node C during the idle time period. If the internal vehicle's target time is 11:21:30, then the time difference between the target time and the start time of the idle time period is greater than the time threshold. At this time, according to the task priority, it is determined whether to wait for the next idle time period, or to increase the comprehensive average speed so that the internal vehicle passes the subsequent impact node C during the current idle time period, or to change the backup route.

[0109] The time difference between the target time and the idle time period is used as the adjustment trigger condition, and a differentiated adjustment strategy is implemented for the comprehensive average speed in combination with the task type. This can ensure the execution priority of each task type while efficiently utilizing the idle resources of the node, thereby achieving dynamic optimization of the backup route.

[0110] Ninth embodiment

[0111] See also Figure 6In one embodiment of the present invention, a navigation system 100 for real-time monitoring and early warning of port vehicles is further provided. The navigation method described in the above embodiment is applied to the navigation system 100. The navigation system 100 includes: a map module 110, which is used to generate preset routes and backup routes based on the reservation records of external container trucks and the port's scheduling plan; an adjustment module 120, which is used to adjust the preset route based on the actual arrival time and real-time traffic flow data; a prediction module 130, which is used to predict a theoretical time period; and an update module 140, which is used to update the preset route. The navigation system has all the technical features of the above navigation method and will not be described in detail here.

[0112] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

Claims

1. A navigation method for real-time monitoring and early warning of port vehicles, characterized in that: The navigation method comprises: Generate a preset route for the external container truck and a backup route for the internal vehicle based on the reservation record of the external container truck and the port's dispatch plan; Adjusting the preset route based on actual arrival time and real-time traffic flow data; When the driving route deviates from the preset route, predict the theoretical time period for the external container truck to pass through each key node on the preset route; Obtaining the driving flow rate of each key node of the path within each theoretical time period, and updating the preset route according to the driving flow rate to obtain an updated route; When the updated route reaches the target execution progress, the subsequent impact nodes of the updated route are obtained, and the backup route is adjusted according to the traffic changes of the subsequent impact nodes; The adjusting of the preset route according to the actual arrival time and real-time traffic flow data specifically includes: obtaining a theoretical traffic volume at the scheduled arrival time according to the reservation record, and comparing the theoretical traffic volume with the actual traffic volume at the actual arrival time to obtain a traffic volume difference; When the vehicle flow difference is greater than a flow threshold, the stage destination of the external container truck is obtained, and an optional path to the stage destination is obtained; Obtaining the road traffic conditions of the optional nodes within each correction time period; Calculate the unit impact duration caused by the external truck passing through the optional node according to the road traffic conditions; Calculating the total impact duration corresponding to each of the optional paths according to the unit impact duration, and determining the optional route that replaces the preset route according to the total impact duration and the driving distance; If the traffic flow difference is less than or equal to the traffic flow threshold, the preset route does not need to be adjusted.

2. The navigation method according to claim 1, wherein: When the driving route deviates from the preset route, predicting the theoretical time period for the external container truck to pass through each key node on the preset route specifically includes: Determine the execution route of the external container truck after the deviation occurs according to the deviation section and the stage destination; Acquiring vehicle data of the external container truck, and determining the start / stop rate and average travel speed of the external container truck based on the vehicle data; The theoretical time period is calculated according to the start-stop rate and the average driving speed.

3. The navigation method according to claim 2, wherein: The obtaining of the driving flow of each key node of the path in each theoretical time period, and updating the preset route according to the driving flow to obtain the updated route specifically includes: Obtaining the estimated flow of the external container truck passing through each key node of the path according to the preset route; Comparing the predicted traffic flow with the driving traffic flow to obtain a node to be replaced on the preset route; Selecting a replacement method for the node to be replaced according to a connection path between the node to be replaced and subsequent key nodes of the path; The preset route is updated according to the replacement method to obtain the updated route.

4. The navigation method according to claim 3, characterized in that: The comparing the predicted traffic volume with the driving traffic volume to obtain the node to be changed on the preset route specifically includes: Calculate the unit delay time of passing through the key nodes of the path according to the expected traffic volume and the driving traffic volume, and calculate the total delay time of maintaining the preset route according to the unit delay time; A congestion coefficient corresponding to the theoretical time period is obtained according to the real-time traffic flow data, and whether the key node on the path is the node to be replaced is determined according to the total delay time and the congestion coefficient.

5. The navigation method according to claim 4, characterized in that: When the updated route reaches the target execution progress, obtaining subsequent impact nodes of the updated route, and adjusting the backup route according to traffic changes of the subsequent impact nodes, specifically includes: Calculate the time impact range of the subsequent impact node due to the updated route; Obtaining a target time for the internal vehicle to arrive at the subsequent impact node according to the preliminary route; When the target time is within the time influence range, adjusting the backup route according to the task type of the internal vehicle and the idle time period of the subsequent influence node; When the target time is outside the time influence range, the backup route does not need to be adjusted before traveling to the subsequent influence node.

6. The navigation method according to claim 5, characterized in that: When the target time is within the time influence range, adjusting the backup route according to the task type of the internal vehicle and the idle time period of the subsequent influence node specifically includes: When the time difference between the idle time period and the target time is less than or equal to a time threshold, reducing the comprehensive average speed of the internal vehicle, and controlling the internal vehicle to pass through the subsequent impact node within the idle time period; When the time difference between the idle time period and the target time is greater than a time threshold, the adjustment method of the comprehensive average speed is determined according to the priority of the task type.

7. A navigation system for real-time monitoring and early warning of port vehicles, characterized by: The navigation method according to any one of claims 1 to 6 is applied to the navigation system, the navigation system comprising: A map module, configured to generate the preset route and the backup route based on the reservation record of the external container truck and the dispatch plan of the port; an adjustment module, the adjustment module being configured to adjust the preset route according to the actual arrival time and the real-time traffic flow data; A prediction module, configured to predict the theoretical time period; An updating module is used to update the preset route.

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