AGV traffic control system and method based on collision detection and arrival time

Abstract

The invention discloses an AGV traffic control system and method based on collision detection and arrival time. The system comprises a collision management module used for testing possible collision between AGVs according to a map; the time table management module is used for determining a time table when the AGV arrives at each point location and adjusting the time table when the time of occupying the road between the AGV tasks has conflict; the collision area management module is used for analyzing whether the AGV tasks to be distributed collide or not and analyzing whether the road occupation time among the AGV tasks has conflicts or not according to the time table, the collision area and the AGV tasks; the collision detection module is used for analyzing whether the path of the to-be-allocated AGV task is in the collision area or not and analyzing whether the path of the to-be-allocated AGV task can enter the collision area or not; and the task allocation determination module is used for determining whether the to-be-allocated AGV task is an allocated task or not. According to the invention, the AGV task execution efficiency and the path utilization rate are improved, and automatic and stable operation can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of traffic control, and in particular to an AGV traffic control system and method based on collision detection and arrival time. Background Art

[0002] Since AGV (Automated Guided Vehicle) can be customized according to different scenarios and needs, it is widely used in many fields such as material transportation and production line coordination. In practical applications, AGV needs to perform path planning and traffic control.

[0003] In terms of path planning, static path planning strategies are often used for delivery tasks with fixed paths and no dynamic environmental changes. Under this strategy, the AGV pre-plans a fixed path and point sequence, and performs delivery tasks according to the set path. This strategy is suitable for stable and repetitive work scenarios, such as production line feeding, material warehousing, etc.

[0004] In the current industrial production environment, AGV traffic control includes area locking mechanism, path reservation mechanism, etc.

[0005] The area locking mechanism refers to manually demarcating several areas, each of which can only accommodate one AGV at a time. When the AGV enters an area, it locks the area and unlocks the area after leaving. Although this method is simple and effective, it has some problems. First, it requires manual division of the locked area, which is time-consuming and labor-intensive, and is prone to errors in complex road conditions and large-scale maps. Second, the division of the area is too fixed, which may cause waste of path resources in the area and reduce traffic efficiency.

[0006] The path reservation mechanism means that after the AGV plans the path, it will occupy the path it needs to travel in advance. If other AGVs conflict with it, they must wait for this AGV to pass before they can pass. The problem with this method is that if the reserved path is long, it may cause multiple other AGVs to wait, resulting in low traffic efficiency.

[0007] In view of this, for AGVs with static path planning, it is urgent to develop an AGV traffic control system and method to avoid the above-mentioned problems in the existing area locking mechanism and path reservation mechanism. Summary of the invention

[0008] In view of the above-mentioned AGV traffic control problem under static path planning, the present invention provides an AGV traffic control system and method based on collision detection and arrival time.

[0009] In a first aspect, the present invention provides an AGV traffic control system based on collision detection and arrival time, comprising:

[0010] The collision management module is used to test possible collisions between AGVs according to the map and obtain collision test results;

[0011] Schedule management module, used to determine the schedule for AGV to arrive at each point according to the AGV task, and to adjust the schedule when there is a conflict in the time of occupying the road between AGV tasks;

[0012] A collision detection module is used to analyze whether the path to which the AGV task is to be assigned will collide with the path of the assigned AGV task according to the collision test results, and to analyze whether the path to which the AGV task is to be assigned will collide with the parked vehicle; the path of the assigned AGV task and the path to which the AGV task is to be assigned are both paths obtained by static path planning;

[0013] A collision area management module, for generating a collision area according to the path of the assigned AGV task and the collision test result, for dynamically managing the collision area according to the schedule and the path of the assigned AGV task, for analyzing whether there is a conflict in the time of occupying the road between AGV tasks according to the schedule, the collision area and the AGV task, and for performing a first function, wherein the first function is to analyze whether the path to which the AGV task is to be assigned is within the collision area and whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and the collision area;

[0014] The task allocation determination module is used to start the collision area management module to execute the first function, which is used to confirm whether the AGV task to be allocated is an allocated AGV task.

[0015] In a preferred embodiment, the first function is to analyze whether the path to which the AGV task is to be assigned is within the collision area. When the path to which the AGV task is to be assigned is within the collision area, the time period in which the path to which the AGV task is to be assigned can enter the collision area is analyzed according to the schedule to obtain an analysis result. Based on the analysis result and the AGV task to be assigned, it is determined whether the AGV task to be assigned can enter the collision area.

[0016] In a preferred embodiment, the analysis of whether the path to which the AGV task is to be assigned is within the collision area is specifically as follows: when the path to which the AGV task is to be assigned will not collide with the path of the assigned AGV task and the parked vehicles, analyzing whether the path to which the AGV task is to be assigned is within the collision area.

[0017] In a preferred embodiment, the method for confirming that the AGV task to be assigned is an assigned AGV task is specifically: when the collision detection module analyzes and determines that the path of the AGV task to be assigned will not collide with the path of the assigned AGV task and the parked vehicle, and when the collision area management module analyzes and determines that the path of the AGV task to be assigned is not within the collision area or the path of the AGV task to be assigned can enter the collision area, confirming that the AGV task to be assigned is an assigned AGV task.

[0018] In a preferred embodiment, the schedule management module includes a schedule initialization determination unit, a schedule update unit, a schedule adjustment unit, and a query unit; the schedule initialization determination unit is used to calculate the time for the AGV to arrive at each point to create a schedule when an AGV task is received but the AGV task is not started; the schedule update unit is used to update the schedule when the AGV performs the task and arrives at a new point; the schedule adjustment unit is used to adjust the schedule when the collision area management module analyzes that there is a conflict in the time of occupying the road between AGV tasks; the query unit is used to provide external schedule query services.

[0019] In a preferred embodiment, the adjusted schedule is adjusted according to the priority of the AGV task, and the schedule for determining the AGV's arrival at each point according to the AGV task includes calculating the time for the AGV to arrive at each point to create a schedule, and updating the schedule when the AGV performs the task and arrives at a new point.

[0020] In a preferred embodiment, the collision management module includes a graphics drawing unit, a collision testing unit, and a first external access unit; the graphics drawing unit is used to take a certain number of equally divided points on each path in the map, and draw a convex polygon of the AGV on each equally divided point; the collision testing unit is used to use the separating axis theorem to test at which points a collision may occur between AGVs and AGVs, and record the points where the collision may occur and the paths corresponding to the points where the collision may occur to obtain the collision test results; the first external access unit is used to provide external access services for the collision test results.

[0021] In a second aspect, the present invention provides an AGV traffic control method based on collision detection and arrival time, comprising:

[0022] According to the map, possible collisions between AGVs are tested to obtain collision test results;

[0023] Determine the timetable for AGV to arrive at each point according to the AGV task;

[0024] Generate collision areas based on the paths of assigned AGV tasks and collision test results;

[0025] Dynamic management of collision zones based on the schedule and paths of assigned AGV tasks;

[0026] According to the timetable, collision area and AGV tasks, analyze whether there is a conflict between the time AGV tasks occupying the road;

[0027] Adjust the schedule when there is a conflict in the time that AGV tasks occupy the road;

[0028] Analyze whether the path of the AGV task to be assigned will collide with the path of the assigned AGV task according to the collision test result; the path of the assigned AGV task and the path of the AGV task to be assigned are both paths obtained by static path planning;

[0029] Analyze whether the path to which the AGV task is to be assigned will collide with parked vehicles;

[0030] Analyze whether the path to which the AGV task is to be assigned is within the collision area and whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and collision area;

[0031] Confirm whether the AGV task to be assigned is an assigned AGV task.

[0032] In a preferred embodiment, when the path to which the AGV task is to be assigned will not collide with the path to which the AGV task has been assigned and the parked vehicles, and when the path to which the AGV task is to be assigned is not within the collision area or when the path to which the AGV task is to be assigned can enter the collision area, the AGV task to be assigned is confirmed as an assigned AGV task.

[0033] In a preferred embodiment, the steps of analyzing whether the path to which the AGV task is to be assigned is within the collision area and analyzing whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and the collision area are performed after analyzing that the path to which the AGV task is to be assigned will not collide with the parked vehicles.

[0034] In a preferred embodiment, after analyzing and determining that the path to which the AGV task is to be assigned is within the collision area, the step of analyzing whether the path to which the AGV task is to be assigned can enter the collision area is performed.

[0035] In a third aspect, the present invention provides a computer-readable storage medium, which includes instructions. When the instructions are executed on a computer, the computer executes the AGV traffic control method based on collision detection and arrival time as described in the second aspect.

[0036] The AGV traffic control system and method based on collision detection and arrival time of the present invention is used for traffic control of AGV under static path planning. Through the collision management module, the automatic detection of possible collisions between AGVs is realized, which greatly reduces the burden of manual operation and reduces the risk of human error. Through the schedule management module and the collision area management module, the AGV traffic situation is predicted in advance, and the probability of AGV collision is almost eliminated. Through the schedule management module and the collision area management module, the safety of AGV traffic is guaranteed, the waste of path resources is reduced, and the utilization rate of path resources, the traffic efficiency and the efficiency of AGV task execution are improved. Through the joint action of the collision detection module, the task allocation determination module, the collision area management module and the schedule management module, it is possible to analyze and judge the AGV task to be assigned to determine whether the AGV task to be assigned can be realized without affecting the execution of the AGV task that has been assigned. For the AGV traffic control under static path planning, the automatic and stable operation of the traffic control is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The framework diagram of the AGV traffic control system based on collision detection and arrival time.

[0038] Figure 2 This is an example graph with a separating axis;

[0039] Figure 3 This is an example graph without a separating axis;

[0040] Figure 4 This is an example diagram of a third-order Bezier curve;

[0041] Figure 5 Flow chart of the AGV traffic control method based on collision detection and arrival time

[0042] Figure 6 It is a timing diagram of the AGV traffic control method based on collision detection and arrival time. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0044] Existing AGV traffic control systems and methods usually include area locking mechanisms, path reservation mechanisms, etc. The area locking mechanism requires manual division of the locked area, which is time-consuming and labor-intensive, and is prone to errors in complex road conditions and large-scale maps. In addition, the divided areas are too fixed, which may cause waste of path resources in the area and reduce traffic efficiency. The path reservation mechanism has low traffic efficiency. Therefore, the existing AGV traffic control system and method has low path resource utilization and low AGV traffic efficiency.

[0045] To this end, the present invention provides an AGV traffic control system, method equipment and computer-readable storage medium based on collision detection and arrival time, which can automatically detect possible collisions between AGVs, and through time measurement, can know in advance where the conflict may occur and adjust the AGV schedule accordingly, so as to avoid bad road conditions in advance and avoid congestion and collision; analyze and judge the AGV tasks to be assigned, so that the AGV tasks to be assigned do not affect the execution of the already assigned AGV tasks, thereby ensuring the automatic and stable operation of AGV traffic control.

[0046] The following embodiments of the present invention can be performed separately, and the embodiments can also be performed in combination with each other, and the embodiments of the present invention do not specifically limit this. In the embodiments of the present invention, "first", "second", etc. are used to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another component. The "and / or" mentioned in the present invention refers to any and all combinations including one or more related listed items.

[0047] Each AGV has a task to perform, which is not limited. Usually, the task is to get from point A to point B. The task may include one or more of time requirements, path requirements, speed requirements, etc. Usually, the task includes path information, time information, and further, speed information. The time information is not specifically limited, and may include the start time of the AGV to perform the task and the time to reach the end point. The AGV needs to have a driving path design to perform the task. It is understandable that the execution of the path occupies road / path resources.

[0048] It should be noted that the path of the assigned AGV task described in this article is the abbreviation of the task path of the assigned AGV task, and the path of the AGV task to be assigned is the abbreviation of the task path of the AGV task to be assigned; the path of the assigned AGV task and the path of the AGV task to be assigned are both static paths, that is, they are both paths obtained by path planning using static path planning methods. Static path planning seeks the shortest path based on constraints such as physical geographic information and traffic rules. The path of the AGV task is a pre-set path that will not change or adjust according to actual conditions such as the environment. An AGV task cannot have a selectable path.

[0049] Next, the AGV traffic control system and method based on collision detection and arrival time and their technical effects are described.

[0050] Figure 1 A schematic diagram of an AGV traffic control system based on collision detection and arrival time is provided in an embodiment, as shown in FIG. Figure 1 As shown, the system provided in this embodiment includes:

[0051] A collision management module 10, used to obtain collision test results based on possible collisions between AGVs according to the map test;

[0052] Schedule management module 20, used to determine the schedule for AGV to arrive at each point according to the AGV task;

[0053] The collision detection module 40 is used to analyze (analyze and determine) whether the path to which the AGV task is to be assigned will collide with the path to which the AGV task has been assigned based on the collision test result, and to analyze whether the path to which the AGV task is to be assigned will collide with a parked vehicle;

[0054] The collision area management module 30 is used to generate a collision area according to the path of the assigned AGV task and the collision test result, to dynamically manage the collision area according to the schedule and the path of the assigned AGV task, to analyze whether there is a conflict in the time of occupying the road between AGV tasks according to the schedule, the collision area and the AGV task, and to perform a first function, which is to analyze (analyze and determine) whether the path of the AGV task to be assigned is within the collision area and to analyze (analyze and determine) whether the path of the AGV task to be assigned can enter the collision area according to the schedule and the collision area; the schedule management module 20 is also used to adjust the schedule when there is a conflict in the time of occupying the road between AGV tasks (analyzed and determined by the collision area management module 30);

[0055] The task allocation determination module 50 is used to start the collision area management module 30 to execute a first function, which is used to confirm whether the AGV task to be allocated is an allocated AGV task.

[0056] It is understandable that the premise for analyzing whether the path to which the AGV task is to be assigned can enter the collision area is that the path to which the AGV task is to be assigned is within the collision area. It is understandable that the path to which the AGV task is to be assigned can enter the collision area if the path to which the AGV task is to be assigned and the collision area do not conflict in time.

[0057] Each module is described in detail below.

[0058] The collision management module 10 is described in detail below:

[0059] The collision management module 10 is used to test possible collisions between AGVs based on the map and the possible paths of the AGVs to obtain collision test results. The collision management module 10 is used to record the collision test results, which include points where collisions may occur and the possible paths of the AGVs corresponding to the points where collisions may occur. Usually, the collision management module 10 obtains the collision test results before other modules (schedule management module 20, collision detection module 40, collision area management module 30 and task allocation determination module 50) work.

[0060] The test is performed by calculation, and the collision management module 10 calculates the paths or points of other AGVs that the AGV may collide with when traveling on the path. The collision test results can be used to restrict other AGVs from using the paths and points where collisions may occur, thereby avoiding collisions between AGVs.

[0061] The collision management module 10 is specifically used to abstract the AGVs into geometric figures (convex polygons) and use the separating axis theorem to test at which points collisions may occur between AGVs. Figure 2 The case where a separating axis exists is exemplified in Figure 3 The case where the separating axis does not exist is exemplified in .

[0062] The collision management module 10 includes a graphics drawing unit, a collision testing unit, and a first external access unit.

[0063] The graphics drawing unit is used to take a certain number of equally divided points on each path of the map and draw a convex polygon of the AGV on each equally divided point. The AGV is abstracted as a rectangle or other convex polygon for easy algorithm processing.

[0064] The collision test unit is used to test the points where collision may occur between AGVs using the separating axis theorem, and record the points where collision may occur and the paths corresponding to the points where collision may occur to obtain the collision test results. The collision test unit tests the paths and points where collision may occur between AGVs using a polygon intersection algorithm.

[0065] The first external access unit is used to provide external access service for collision test results. The collision detection module 40 obtains the collision test results through the first external access unit.

[0066] In some embodiments, the collision management module 10 also includes a map conversion unit for importing the AGV operation map into it and converting the AGV operation map into a standard map. The standard map provides a basis for the subsequent algorithm implementation. The standard map is the map in the graphics drawing unit. The standard map is a map with uniformly specified coordinate axes, points, paths, directions, and speeds. Specifically, the AGV operation map refers to a map provided by the AGV manufacturer for AGV driving, which includes information such as points (coordinates), straight lines or third-order Bezier curve paths (coordinates, directions), and vehicle speeds on the paths (average values); the standard map refers to the map format used by the system where the AGV traffic control system of this embodiment is located, which will convert the AGV manufacturer's map to meet the requirements of this system, including points (coordinates), third-order Bezier curve paths (coordinates, directions, lengths), and vehicle speeds on the paths (average values). Taking a certain amount of equally divided points on each path of the map is to take a certain amount of equally divided points on the third-order Bezier curve path of the map.

[0067] The AGV traffic control system systematically calculates the collision test results first through the collision management module 10. The collision management module 10 is not required to be based on certain specific AGV tasks. The collision management module 10 is based on the map to determine which points will cause collisions between AGVs when the AGVs are driving. For example, an AGV traveling south in the leftmost lane and an AGV traveling west and preparing to turn north in the rightmost lane will collide at an intersection. The point at the intersection and the corresponding driving path are recorded as the collision test results.

[0068] The collision management module 10 uses Bezier curves to calculate the distance and direction of the curved path. Specifically, in the standard map, the collision management module 10 converts all paths (including straight lines) in the map into third-order Bezier curves. The third-order Bezier curves are used to calculate the path length, and then combined with the AGV speed, the time it takes for the AGV to pass the path is calculated; the collision management module 10 is used to calculate the coordinates of the equally divided points and the direction of the AGV at the equally divided points, and calculate the rectangular area where the AGVs collide at the equally divided points, and then obtain the collision test results.

[0069] Figure 4 is a third-order Bezier curve, including four control points, namely P0, P1, P2, and P3. The following is the coordinate formula of the third-order Bezier curve,

[0070]

[0071] Among them, t represents the position of the point on the curve, and its value ranges from 0 to 1. A t value of 0 represents the starting point P0, and a t value of 1 represents the end point P3. P0, P1, P2, and P3 in the formula represent the coordinate values ​​of control point P0, control point P1, control point P2, and control point P3 respectively.

[0072] The method of using Bezier curve to calculate length is: take a very small length Δt, find the straight-line distance between the two end points of the very small length, and calculate according to the fifth-order node table of Gauss-Legendre integral to find the approximate length of the curve, that is, the distance of the curve path.

[0073] The arc of the equally divided points on the curved path in the map is calculated as:

[0074] Based on Formula 3 (1 - t) (1 - t) (P1 - P0) +6 (1 - t) t (P2 -P1) +3 t t (P3 - P2) Computes the derivative of a Bezier curve at a specified parameter value and then uses the inverse tangent function to find the angle in radians.

[0075] The schedule management module 20 is described in detail below:

[0076] The schedule management module 20 is used to determine the schedule for the AGV to arrive at each point according to the AGV task; and is used to adjust the schedule when the collision area management module 30 analyzes that the time for the AGV task to occupy the road (occupy the path) has a conflict, so that the time for the AGV tasks to occupy the road does not conflict. If it is not specified in this article whether the AGV task has been assigned or is to be assigned, it is not limited, and it can usually be an assigned AGV task or an AGV task to be assigned.

[0077] The schedule management module 20 is used to determine the schedule for the AGV to arrive at each point according to the assigned AGV task (execution status). If the assigned AGV task has not been executed, the schedule is the schedule for the AGV task's path to arrive at each point. If the assigned AGV task has been executed, the schedule is the schedule corresponding to the subsequent journey. In this embodiment, the paths of the AGV tasks are all static path planning, and each AGV task has only one path. It can be understood that if the path from the starting point to the end point is called a route, the number of routes of the AGV task is 1.

[0078] The schedule management module 20 is used to determine the schedule for the AGV to arrive at each point according to the AGV task to be assigned. The schedule obtained at this time is the schedule for the path of the AGV task to be assigned to arrive at each point.

[0079] The AGV task includes the path of the AGV. Further, the AGV task may also include the time requirement for the AGV to reach a certain point, and may also include the speed of the AGV. Here, the specific content of the AGV task is not specifically limited.

[0080] The schedule management module 20 includes a schedule initial determination unit, a schedule update unit, a schedule adjustment unit, and a query unit.

[0081] The schedule initial determination unit is used to calculate the time for the AGV to arrive at each point and create a schedule when the AGV task is received but the AGV task is not started. The received AGV task can be an assigned AGV task or an AGV task to be assigned.

[0082] The schedule updating unit is used to update the schedule when the AGV performs a task and arrives at a new point: recalculate the time taken by the AGV to perform the subsequent path in the task, and update the time when the AGV arrives at the subsequent point to ensure real-time update and relative accuracy of the schedule.

[0083] The schedule adjustment unit is used to adjust the schedule when the collision area management module 30 analyzes that there is a conflict in the time for AGV tasks to occupy the road. Specifically, when there is a conflict in the time for N (N is an integer greater than or equal to 2) AGVs to execute the task path, the schedule is adjusted, and the schedule of N-1 AGVs is postponed according to the task information of the AGVs with time conflicts, so that the time for multiple AGVs to occupy the path resources does not conflict. The determination of postponement usually needs to consider the priority of AGV task information, that is, the schedule adjustment unit is used to adjust the schedule according to the priority of the AGV task when the collision area management module 30 analyzes that there is a conflict in the time for AGV tasks to occupy the road. The priority can be a pre-set priority level or can be determined based on the time requirement information in the task information.

[0084] The query unit is used to provide a schedule query service to the outside. The collision area management module 30 obtains the schedule through the collision area management module 30.

[0085] It can be understood that the schedule initial determination unit, the schedule update unit and the schedule adjustment unit all calculate and determine the schedule based on the distance on the map, the speed of the AGV and the path of the AGV.

[0086] The collision area management module 30 is described in detail below:

[0087] The collision area management module 30 is specifically used to determine the points where collision may occur between the paths of the assigned AGV tasks according to the collision test results and the paths of the assigned AGV tasks, and generate a collision area; the collision area is an area where the paths may collide between different assigned AGV tasks, and the collision area includes information about the paths that may collide, that is, a path set (a set of paths of the assigned AGV tasks that may collide), and the collision area also includes vehicle member information, that is, based on this, it can be known which vehicles will enter this collision area, and which vehicle occupies the collision area at this moment. It is understandable that there may be no vehicle occupying the collision area temporarily.

[0088] The collision area management module 30 is used to dynamically manage the collision area according to the schedule; and is used to dynamically manage the collision area according to the schedule and the path of the assigned AGV task.

[0089] The path of an AGV task can be just one, or the path of an AGV task can include all planned paths under the AGV task (possibly achievable paths, such as paths designed with or without considering collisions with other AGVs). Each AGV task usually has more than one AGV task.

[0090] The analysis of whether the path to be assigned is within the collision area and whether the path to be assigned can enter the collision area according to the schedule and the collision area specifically includes: analyzing whether the path to be assigned (i.e., the path to which the AGV task is to be assigned) is within the collision area, and when the path to be assigned is within the collision area, analyzing the time period in which the path to be assigned can enter the collision area according to the schedule to obtain an analysis result, and judging whether the path to be assigned can enter the collision area according to the analysis result of the time period in which the path can enter the collision area and the AGV task to be assigned (e.g., time requirement).

[0091] The collision region management module 30 includes a collision region generating unit, a collision region managing unit, and an analyzing unit.

[0092] The collision area generation unit is used to generate a collision area according to the assigned AGV task path and collision test results, and add collision area member information; the collision area member information includes the AGV (name) corresponding to the collision area. After the path of the AGV task is planned, the collision area generation unit generates a collision area according to the collision test results, and adds collision area member information, including road information near the collision point (called collision path), AGV name, AGV task path and other information.

[0093] The collision area management unit is used to dynamically manage the collision area according to the schedule, the assigned AGV tasks and the collision test results. The dynamic management includes adding the collision area, updating the collision area and managing the collision area member information.

[0094] The update of the collision area is specifically characterized as follows: after the schedule changes, the collision area management unit synchronously updates the collision area member information, including the path of the AGV task and the collision path corresponding to the path of the AGV task. The update includes updating the collision path of the collision area, because the collision area may shrink or disappear according to the movement of the AGV, and it needs to be updated at any time to maintain the most accurate information.

[0095] The management of the collision area member information is specifically characterized as follows: when an AGV enters or exits the collision area, the collision area member information corresponding to the AGV needs to be added or deleted.

[0096] The analysis unit is used to analyze whether there is a conflict in the time when AGV tasks occupy the road according to the timetable, the collision area and the AGV tasks, and to analyze whether the path to be assigned is in the collision area and whether the path to be assigned can enter the collision area according to the timetable and the collision area. Specifically, the analysis unit is used to analyze whether the path to be assigned is in the collision area, and to analyze whether the time period of the AGV task to be assigned can enter the collision area according to the timetable when the path to be assigned is in the collision area to obtain an analysis result, and to determine whether the AGV task to be assigned can enter the collision area according to the analysis result.

[0097] The analysis unit is started when the collision detection module 40 determines that the path to be assigned will not collide with the assigned path and the parked vehicle. That is, the analysis unit is used to analyze whether the path to be assigned is within the collision area when the path to be assigned will not collide with the assigned path and the parked vehicle, and to analyze the time period when the AGV task to be assigned can enter the collision area according to the schedule to obtain the analysis result when the path to be assigned is within the collision area, and to determine whether the AGV task to be assigned can enter the collision area according to the analysis result.

[0098] The time period during which the AGV task to be assigned can enter the collision area according to the timetable analysis is specifically: the time period during which the AGV task to be assigned can enter the collision area according to the timetable analysis, or the time period during which the AGV task to be assigned can enter the collision area according to the timetable and the scheduling results of the AGVs that schedule the AGV task to be assigned and the assigned AGV task. It can be understood that the time period during which the AGV can enter the collision area is a time period during which no AGV collision will occur after entering.

[0099] In some embodiments, when executing the first function, the collision area management module 30 simultaneously starts analyzing whether there is a conflict in the road occupation time between the assigned AGV tasks and the AGV tasks to be assigned based on the schedule, collision area and AGV tasks, so as to improve the efficiency of starting and completing new AGV tasks.

[0100] In this embodiment, the collision area management module 30 can not only analyze whether the AGV can enter, but also analyze whether the schedule needs to be changed, and can adjust the schedule according to the schedule changes, that is, the collision area management module 30 and the schedule management module 20 can jointly realize the scheduling of AGV.

[0101] The collision area management module 30 can query whether other AGVs have entered the collision area where the AGV task is to be assigned, or whether the AGV can enter the collision area in the current time period. AGVs that are assigned AGV tasks earlier or later than a certain time period cannot enter directly and need to wait for reassignment or arrive at the specified time.

[0102] The collision area management module 30 can update the collision area information according to the changes in the schedule. After updating the collision area, the collision area management module 30 checks whether the AGV with the changed schedule has a time conflict with other AGVs in the collision area. If a conflict occurs, the collision area management module 30 notifies the schedule management module 20 to adjust the time and change the planned time of the AGV with the conflict, that is, to schedule the AGV.

[0103] The collision area management module 30 is further used to update the collision area according to the assigned AGV tasks determined by the task allocation determination module 50, and mark the entered area in the collision area member information.

[0104] The collision detection module 40 is described in detail below:

[0105] When allocating path resources, it is responsible for analyzing whether the AGV of the AGV task to be assigned will collide with the assigned path or with a parked vehicle. If there is a path where the AGV task to be assigned will not collide with the assigned AGV task path or with a parked vehicle, it is considered that the path to be assigned will not collide with the assigned path and the parked vehicle. It is understandable that if a collision occurs, the path cannot be assigned, which is defined as not being assigned temporarily, and the assignment will be retried after a period of time. Specifically, if each planned path of the AGV task to be assigned will collide with the assigned path or with a parked vehicle, the AGV task to be assigned will be tried again after a preset time or when other conditions are met.

[0106] The task allocation determination module 50 is described in detail below:

[0107] The task allocation determination module 50 is used to confirm that the AGV task to be allocated is an allocated AGV task. Specifically, the task allocation determination module 50 is used to confirm that the AGV task to be allocated becomes an allocated AGV task when the collision detection module 40 analyzes and determines that the path of the AGV task to be allocated will not collide with the path of the allocated AGV task and the parked vehicle, and when the collision area management module 30 analyzes and determines that the path of the AGV task to be allocated is not within the collision area or the path of the AGV task to be allocated can enter the collision area, otherwise, confirm that the AGV task to be allocated cannot be used as an allocated AGV task.

[0108] The task allocation determination module 50 includes a starting unit and a task confirmation unit.

[0109] The starting unit is used to start the collision area management module 30 to execute the first function.

[0110] The task confirmation unit is used to confirm that the AGV task to be assigned is the assigned AGV task when the path to be assigned will not collide with the assigned path and the parked vehicle, and when the path to be assigned is not in the collision area or when the path to be assigned can enter the collision area.

[0111] The confirmation task unit is also used to cancel the AGV task to be assigned when the path to be assigned will collide with the assigned path or parked vehicles; and to cancel the AGV task to be assigned when the path to be assigned is within the collision area but the path to be assigned can enter the collision area.

[0112] Through the task allocation determination module 50, the collision area management module 30 and the schedule management module 20, the time conflict analysis is realized when allocating path resources. Whether the current AGV task to be allocated is in the collision area, and whether the collision area allows the path to be allocated to enter the collision area in the time period corresponding to the path to be allocated. If it is in the collision area and the path to be allocated is not allowed to enter the collision area in the time period corresponding to the path to be allocated, the path cannot be allocated and the path to be allocated is cancelled. Not allowing the path to be allocated to enter the collision area in the time period corresponding to the path to be allocated means that the AGV task to be allocated and the allocated AGV task have a time conflict in the collision area.

[0113] For the AGV tasks to be assigned that have not passed the analysis and detection by the detection module, the assignment can be delayed for a certain period of time, and the time information of the AGV tasks to be assigned can be relaxed to increase the probability that the collision area allows the assigned path to enter the collision area during the time period corresponding to the assigned path.

[0114] See also Figure 5 , this embodiment provides an AGV traffic control method based on collision detection and arrival time, including:

[0115] (Collision management module 10) testing possible collisions between AGVs according to the map to obtain collision test results;

[0116] (Schedule management module 20) determines the schedule for the AGV to arrive at each point according to the AGV task;

[0117] (Collision area management module 30) generates a collision area according to the path of the assigned AGV task and the collision test result; the path of the assigned AGV task is obtained by static path planning;

[0118] (Collision area management module 30) dynamically manages the collision area according to the schedule and the path of the assigned AGV task;

[0119] (Collision area management module 30) analyzing whether there is a conflict in the road occupation time between AGV tasks according to the timetable, collision area and AGV tasks;

[0120] (The schedule management module 20) adjusts the schedule when (the collision area management module 30 analyzes and determines) there is a conflict in the time that the AGV tasks occupy the road;

[0121] (Collision detection module 40) analyzing whether the path of the AGV task to be assigned will collide with the path of the assigned AGV task according to the collision test result;

[0122] (Collision detection module 40) analyzing whether the path to which the AGV task is to be assigned will collide with the parked vehicle; the path to which the AGV task is to be assigned is obtained by static path planning;

[0123] (Collision area management module 30) analyzing whether the path to which the AGV task is to be assigned is within the collision area and analyzing whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and the collision area;

[0124] (Task allocation determination module 50 ) Confirm / determine whether the AGV task to be allocated is an allocated AGV task.

[0125] It should be understood that the above method does not represent or imply that all steps must be executed in this order. A person skilled in the art can transform or change the execution order of the above steps based on the present invention. Some embodiments of the above method are illustrated below.

[0126] Specifically, when (the collision detection module 40 analyzes and determines) that the path of the AGV task to be assigned will not collide with the path of the assigned AGV task and the parked vehicles, and when (the collision area management module 30 analyzes and determines) that the path of the AGV task to be assigned is not within the collision area or the path of the AGV task to be assigned can enter the collision area, (the task allocation determination module 50) determines that the AGV task to be assigned can be used as the assigned AGV task; otherwise, it determines that the AGV task to be assigned cannot be used as the assigned AGV task.

[0127] See also Figure 6 , a specific embodiment of the above method is given, comprising the following steps:

[0128] S1, the collision management module 10 obtains a map and performs a collision test between AGVs to obtain a collision test result;

[0129] S2, the collision area management module 30 and the time management module receive the AGV task or update the AGV task, and the time management module determines the schedule;

[0130] S3, the collision area management module 30 obtains the collision test result of the collision management module 10;

[0131] S4, the collision area management module 30 adds the collision area according to the AGV task and the collision test result obtained in S2;

[0132] S5, the time management module adjusts the schedule in real time according to the execution status of the AGV task;

[0133] S6. The collision area management module 30 analyzes whether there is a conflict between the time when the AGVs occupy the path (occupy a certain path resource) according to the collision area and the latest schedule. If there is a conflict, the time management module adjusts the schedule;

[0134] S7, the collision detection module 40 obtains the AGV task to be assigned, and analyzes whether the AGV task to be assigned will collide with the assigned AGV task path according to the path of the AGV task to be assigned and the collision test result, and analyzes whether the AGV task to be assigned will collide with the parked vehicle according to the path of the AGV task to be assigned; if it will not collide with the assigned AGV task path and will not collide with the parked vehicle, proceed to S8, otherwise, wait for the next AGV task to be assigned; here, the parked vehicle refers to the parked AGV, and the method for obtaining the parking information of the parked vehicle is not limited.

[0135] S8, the collision detection module 40 determines whether the task allocation determination module 50 can be allocated

[0136] The task allocation determination module 50 starts the collision area management module 30 to execute the first function. The collision area management module 30 analyzes whether the path to which the AGV task is to be allocated is within the collision area and whether the path to which the AGV task is to be allocated can enter the collision area according to the schedule and the collision area. When the collision area management module 30 determines that the path to which the AGV task is to be allocated is not within the collision area or the path to which the AGV task is to be allocated can enter the collision area, S9 is performed;

[0137] S9, the task allocation determination module 50 confirms that the AGV task to be allocated is an allocated AGV task; the collision area management module 30 updates the collision area according to the task that has recently become the allocated AGV task.

[0138] When the AGV traffic control method based on collision detection and arrival time is implemented, the AGV traffic control system based on collision detection and arrival time in any of the above embodiments can be referred to to implement AGV traffic control, and the specific implementation steps will not be repeated.

[0139] The present invention also provides a computer-readable storage medium, which includes instructions. When the instructions are executed on a computer, the computer executes each step of the AGV traffic control method based on collision detection and arrival time in any of the above embodiments.

[0140] According to the method of the present invention, an electronic device can be implemented, which includes: a memory; one or more processors; one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include instructions for executing the AGV traffic control method based on collision detection and arrival time according to any of the above embodiments.

[0141] The effects of the AGV traffic control system and method based on collision detection and arrival time of the present invention are:

[0142] Through the collision management module 10, the automatic detection of possible collisions between AGVs is realized, which greatly reduces the burden of manual operation and reduces the risk of human error. Through the schedule management module 20 and the collision area management module 30, the AGV traffic situation is predicted in advance, and the order can be arranged before the AGV arrives at the intersection, avoiding congestion at the intersection, and almost eliminating the probability of collision between AGVs. Through the schedule management module 20 and the collision area management module 30, the safety of AGV traffic is guaranteed, the waste of path resources is reduced, the utilization rate of path resources is improved, the traffic efficiency is improved, and the efficiency of AGV task execution is improved. Through the joint action of the collision detection module 40, the task allocation determination module 50, the collision area management module 30 and the schedule management module 20, it is possible to analyze and judge the AGV task to be assigned to determine whether the AGV task to be assigned can be realized without affecting the execution of the AGV task that has been assigned, ensuring that the traffic control of AGV under static path planning can operate automatically and stably.

[0143] The present invention is applicable to most scenarios and can quickly adapt after the scenario is changed, thereby improving the applicability and flexibility of the system.

[0144] "Deadlock" is a term in the computer field, which refers to a phenomenon of obstruction caused by competition for resources or communication between two or more processes during execution. Without external force, they will not be able to move forward. In the field of traffic control, "deadlock" means: AGV1 is located in a control area A and needs to enter control area B, while AGV2 is located in control area B and needs to enter control area A. The tasks of the two vehicles cannot continue to execute, which is called "deadlock". In the prior art, if the "deadlock" problem occurs, it will seriously hinder the completion of the task and may hinder the execution of other AGVs or tasks. The collision area management module 30 and the schedule management module 20 of the present application cooperate, and there are no clear control areas, that is, there will be no deadlock problem. The collision area management module 30 and the schedule management module 20 cooperate to schedule each AGV, which improves the efficiency of AGV task execution and ensures the comprehensive and stable advancement of AGV traffic.

[0145] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0146] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0147] The present invention is described with reference to the flowcharts and / or block diagrams of the methods and systems according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0148] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0149] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0150] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

Claims

1. AGV traffic control system based on collision detection and arrival time, characterized in that: include: The collision management module is used to test possible collisions between AGVs according to the map and obtain collision test results; Schedule management module, used to determine the schedule for AGV to arrive at each point according to the AGV task, and to adjust the schedule when there is a conflict in the time of occupying the road between AGV tasks; A collision detection module is used to analyze whether the path to which the AGV task is to be assigned will collide with the path of the assigned AGV task according to the collision test results, and to analyze whether the path to which the AGV task is to be assigned will collide with the parked vehicle; the path of the assigned AGV task and the path to which the AGV task is to be assigned are both paths obtained by static path planning; A collision area management module, for generating a collision area according to the path of the assigned AGV task and the collision test result, for dynamically managing the collision area according to the schedule and the path of the assigned AGV task, for analyzing whether there is a conflict in the time of occupying the road between AGV tasks according to the schedule, the collision area and the AGV task, and for performing a first function, wherein the first function is to analyze whether the path to which the AGV task is to be assigned is within the collision area and whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and the collision area; The task allocation determination module is used to start the collision area management module to execute the first function, which is used to confirm whether the AGV task to be allocated is an allocated AGV task.

2. The AGV traffic control system based on collision detection and arrival time as claimed in claim 1, characterized in that: The first function is to analyze whether the path to which the AGV task is to be assigned is within the collision area. When the path to which the AGV task is to be assigned is within the collision area, the time period in which the path to which the AGV task is to be assigned can enter the collision area is analyzed according to the schedule to obtain the analysis result. Based on the analysis result and the AGV task to be assigned, it is determined whether the AGV task to be assigned can enter the collision area.

3. The AGV traffic control system based on collision detection and arrival time as claimed in claim 1, characterized in that: The analyzing whether the path to which the AGV task is to be assigned is within the collision area specifically includes: analyzing whether the path to which the AGV task is to be assigned is within the collision area when the path to which the AGV task is to be assigned will not collide with the path to which the AGV task has been assigned and the parked vehicles.

4. The AGV traffic control system based on collision detection and arrival time as claimed in claim 1, characterized in that: The method for confirming that the AGV task to be assigned is an assigned AGV task is specifically used for: when the collision detection module analyzes and determines that the path of the AGV task to be assigned will not collide with the path of the assigned AGV task and the parked vehicle, and when the collision area management module analyzes and determines that the path of the AGV task to be assigned is not within the collision area or the path of the AGV task to be assigned can enter the collision area, confirming that the AGV task to be assigned is an assigned AGV task.

5. The AGV traffic control system based on collision detection and arrival time as claimed in claim 1, characterized in that: The schedule management module includes a schedule initialization determination unit, a schedule update unit, a schedule adjustment unit, and a query unit; the schedule initialization determination unit is used to calculate the time for the AGV to arrive at each point to create a schedule when an AGV task is received but the AGV task is not started; the schedule update unit is used to update the schedule when the AGV performs the task and arrives at a new point; the schedule adjustment unit is used to adjust the schedule when the collision area management module analyzes that there is a conflict in the time of occupying the road between AGV tasks; the query unit is used to provide external schedule query services.

6. The AGV traffic control system based on collision detection and arrival time as claimed in claim 1, characterized in that: The adjustment schedule is an adjustment schedule based on the priority of the AGV task. The determination of the schedule for the AGV to arrive at each point based on the AGV task includes calculating the time for the AGV to arrive at each point to create a schedule, and updating the schedule when the AGV performs the task and arrives at a new point.

7. The AGV traffic control system based on collision detection and arrival time as claimed in claim 1, characterized in that: The collision management module includes a graphics drawing unit, a collision testing unit, and a first external access unit; the graphics drawing unit is used to take a certain amount of equally divided points on each path in the map and draw a convex polygon of the AGV on each equally divided point; the collision testing unit is used to use the separating axis theorem to test at which points a collision may occur between AGVs and AGVs, and record the points where the collision may occur and the paths corresponding to the points where the collision may occur to obtain the collision test results; the first external access unit is used to provide external access services for the collision test results.

8. AGV traffic control method based on collision detection and arrival time, characterized in that: include: According to the map, possible collisions between AGVs are tested to obtain collision test results; Determine the timetable for AGV to arrive at each point according to the AGV task; Generate collision areas based on the paths of assigned AGV tasks and collision test results; Dynamic management of collision zones based on the schedule and paths of assigned AGV tasks; According to the timetable, collision area and AGV tasks, analyze whether there is a conflict between the time AGV tasks occupying the road; Adjust the schedule when there is a conflict in the time that AGV tasks occupy the road; Analyze whether the path of the AGV task to be assigned will collide with the path of the assigned AGV task according to the collision test result; the path of the assigned AGV task and the path of the AGV task to be assigned are both paths obtained by static path planning; Analyze whether the path to which the AGV task is to be assigned will collide with parked vehicles; Analyze whether the path to which the AGV task is to be assigned is within the collision area and whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and collision area; Confirm whether the AGV task to be assigned is an assigned AGV task.

9. The AGV traffic control method based on collision detection and arrival time as claimed in claim 8, characterized in that: The steps of analyzing whether the path to which the AGV task is to be assigned is within the collision area and analyzing whether the path to which the AGV task is to be assigned can enter the collision area according to the schedule and the collision area are performed after analyzing that the path to which the AGV task is to be assigned will not collide with the parked vehicle.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes instructions, which, when executed on a computer, enable the computer to execute the AGV traffic control method based on collision detection and arrival time as claimed in claim 8 or 9.

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