Path planning method, device and medium for multi-robot collaborative transportation

Abstract

The present invention relates to the technical field of mobile robot path planning, and in particular to a path planning method, device and medium for collaborative transportation of multiple robot models. In an embodiment of the present invention, when planning a local path, not only whether the forward planning point is in an occupied state is considered, but also whether the associated points of the planning point are in an occupied state is considered. Only when the planning point and its corresponding associated points are both in an occupied state, can the planning point be occupied by the current mobile robot. In this way, it is possible to avoid collisions between large mobile robots and mobile robots located at associated points when they move to the planning point, effectively adapt to the mixed running of mobile robots of different models in the venue, reduce the occurrence of emergency braking, and facilitate the transportation of precision devices such as silicon wafers and semiconductors.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile robot path planning, and in particular to a path planning method, device and medium for collaborative transportation of multiple robot models. Background Art

[0002] Currently, some large workshops (such as photovoltaic and automotive production lines) require multiple mobile robots of different models to collaboratively transport materials. However, due to site constraints, it's not possible to use the same type of mobile robots in the same area and along the same route. Consequently, different models of mobile robots are often mixed together on site. Because different models vary in size, there are points along the route where they interfere with each other. When a larger mobile robot passes through a point, it also occupies other points. When other mobile robots also need to pass through these interfering points, they may need to brake to avoid them. Even if the emergency brake is applied promptly, the load on the mobile robots can easily shift due to inertia, causing damage. This is detrimental to the transportation of precision components such as silicon wafers and semiconductors. Summary of the Invention

[0003] The main purpose of the present invention is to provide a path planning method, device and medium for collaborative transportation of multiple robots, aiming to provide a path planning method that reduces conflicts and avoids obstacles.

[0004] To achieve the above objectives, the first aspect of the present invention provides a path planning method for multi-robot collaborative transportation, comprising:

[0005] Plan the optimal global path points for all mobile robots;

[0006] Perform local path planning for each mobile robot in the current frame in order according to the task priority. Local path planning includes:

[0007] Get the current position of the mobile robot, and plan several planned positions along its global path starting from the current position;

[0008] Determine whether the planned location is in an occupiable or unoccupiable state;

[0009] If the planned point is in an occupiable state, then determine whether the associated point of the planned point is in an unoccupiable state; wherein the associated point is a point whose distance to the planned point is less than or equal to the maximum radius of the current mobile robot; if the associated point of the planned point is in an unoccupiable state, then adjust the planned point to an unoccupiable state;

[0010] If the associated point of the planned point is in an occupiable state, then determine whether the distance between the planned point and the adjacent point in the unoccupiable state is less than the obstacle avoidance distance, which is the sum of the maximum radius of the current mobile robot, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point; if it is less than, the planned point is adjusted to an unoccupiable point; if it is greater than or equal to, the planned point is an occupiable point;

[0011] The planned point between the current point and the first planned point in an unoccupiable state is selected as the local path of the current mobile robot.

[0012] Optionally, after planning the local path of the current mobile robot, the planned points and their associated points of the local path of the current mobile robot are adjusted to an unoccupiable state.

[0013] Optionally, after all mobile robots complete the local path planning for the current frame, a local path is issued to each mobile robot; and the local path planning for the next frame is performed.

[0014] Optionally, in determining whether a plurality of planned points are in an unoccupiable state, each point is determined in sequence along its own global path, and the determination is terminated when one of the planned points is in an unoccupiable state.

[0015] Optionally, in local path planning, when a planning point is occupied by the same mobile robot for a time exceeding a preset time, the planning point is determined to be a blocking point;

[0016] Using the improved A* algorithm, the path cost of the congestion point is adjusted to the highest value, and a new global route is replanned.

[0017] Optionally, the task priority order includes the following steps:

[0018] Obtain the order in which the mobile robot receives the target, the final path length to the destination, and the number of turns along the path;

[0019] Calculate the task priority of each mobile robot using the following formula:

[0020] ;

[0021] in, is the task priority of the j-th mobile robot, It is a 0-1 decision variable, which is set to 1 when the end point is the machine point, and is set to 0 when the end point is the standby point or the charging point. It is the sum of all node distances from the starting point to the end point of the global path; is a 0-1 decision variable, traversing the global path n When the node passes throughi When a node needs to be rotated, set it to 1, and when it does not need to be rotated, set it to 0. is the target machine waiting time; 、 、 are specific gravity respectively;

[0022] Sort by task priority. If the task priorities are equal, arrange them in the order of receiving the target tasks.

[0023] A second aspect of the present invention discloses a path planning device for collaborative transportation of multiple robots, comprising:

[0024] Global path planning module, used to plan the optimal global path points for all mobile robots;

[0025] The local path planning module is used to plan the local path of each mobile robot in the current frame in sequence according to the task priority. The local path planning module includes:

[0026] The local planning unit is used to obtain the current position of the mobile robot and plan several planned positions along its own global path starting from the current position;

[0027] A state judgment unit is used to judge whether the planned point is in an occupiable state or an unoccupiable state;

[0028] If the planned point is in an occupiable state, then determine whether the associated point of the planned point is in an unoccupiable state; wherein the associated point is a point whose distance to the planned point is less than or equal to the maximum radius of the current mobile robot; if the associated point of the planned point is in an unoccupiable state, then adjust the planned point to an unoccupiable state;

[0029] If the associated point of the planned point is in an occupiable state, then determine whether the distance between the planned point and the adjacent point in the unoccupiable state is less than the obstacle avoidance distance, where the obstacle avoidance distance is the sum of the maximum radius of the current mobile robot, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point; if less than, the planned point is adjusted to an unoccupiable point; if greater than or equal to, the planned point is an occupiable point;

[0030] The local path updating unit is used to select a planned point between the current point and the first planned point in an unoccupiable state as the local path of the current mobile robot.

[0031] Optionally, it also includes a sending module for sending a local path to each mobile robot after all mobile robots complete the local path planning of the current frame; and triggering the local path planning module to plan the local path planning of the next frame

[0032] A third aspect of the present invention discloses an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method described in any one of the first aspects of the present invention is implemented.

[0033] A fourth aspect of the present invention discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any one of the methods described in the first aspect of the present invention.

[0034] The technical solution provided by the present invention can have the following beneficial effects:

[0035] In the path planning method for collaborative transportation of multiple robots provided by the present invention, when planning a local path, not only whether the planned point ahead is in an occupied state is considered, but also whether the associated points of the planned point are in an occupied state. Only when the planned point and its corresponding associated points are both in an occupied state can the planned point be occupied by the current mobile robot. In this way, it is possible to avoid collisions between large mobile robots moving to the planned point and mobile robots located at the associated points. It is suitable for mobile robots of different models to run together in the field, reducing the occurrence of emergency braking, which is beneficial to the transportation of precision devices such as silicon wafers and semiconductors.

[0036] Furthermore, even when both the planned point and its corresponding associated point are in an occupiable state, further consideration is given to whether there is sufficient safety distance between the planned point and any occupied adjacent mobile robots. Therefore, the system determines whether the distance between the planned point and an unoccupiable adjacent point is less than the obstacle avoidance distance, which is the sum of the current mobile robot's maximum radius, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point. Only when this distance is greater than or equal to the obstacle avoidance distance can the planned point be occupied by the current mobile robot. This effectively avoids the need for the current mobile robot to avoid the mobile robot occupying the adjacent point after moving to the planned point, minimizing the impact on other mobile robots and facilitating smooth material transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0038] Figure 1 A schematic flow chart of a method for path planning for multi-robot collaborative transportation according to an embodiment of the present invention;

[0039] Figure 2 A schematic diagram of a path planning method for multi-robot collaborative transportation according to an embodiment of the present invention;

[0040] Figure 3 A schematic flow chart of a method for path planning for multi-robot collaborative transportation according to another embodiment of the present invention;

[0041] Figure 4 FIG. 1 is a schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0043] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0044] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0045] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing throughout the text is to include three parallel solutions. Taking "A and / or B as an example", it includes solution A, or solution B, or solutions that meet both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0046] Currently, some large workshops (such as photovoltaic and automotive production lines) require multiple mobile robots of different models to collaboratively transport materials. However, due to site constraints, it's not possible to use the same type of mobile robots in the same area and along the same route. Consequently, different models of mobile robots are often mixed together on site. Because different models vary in size, there are points along the route where they interfere with each other. When a larger mobile robot passes through a point, it also occupies other points. When other mobile robots also need to pass through these interfering points, they may need to brake to avoid them. Even if the emergency brake is applied promptly, the load on the mobile robots can easily shift due to inertia, causing damage. This is detrimental to the transportation of precision components such as silicon wafers and semiconductors.

[0047] To this end, the multi-robot coordinated transport path planning method disclosed in the first aspect of the present invention can be executed by a server that centrally manages the multiple mobile robots. The mobile robots referred to in the present invention are devices that move according to planned points on the ground, such as unmanned transport equipment such as AGVs and IGVs.

[0048] like Figure 1 As shown, a path planning method for multi-robot collaborative transportation according to an embodiment of the present invention is described, comprising the following steps:

[0049] Step S1: planning the optimal global path points of all mobile robots; in an optional embodiment, the optimal global path of all mobile robots can be planned by an improved A* algorithm.

[0050] Step S2: Perform local path planning for each mobile robot in the current frame, sequentially based on task priority. Task priority is determined based on a combination of information, including the order in which the mobile robot receives the targets, the final path length to the destination, and the number of turns along the path. The specific evaluation rules are described below.

[0051] Local path planning includes:

[0052] Step S21: obtaining the current position of the current mobile robot, and planning a number of planned positions along its own global path starting from the current position;

[0053] Step S22: Determine whether the planned point is in an occupiable state or an unoccupiable state; the occupiable state means that the point is not planned on the local path, and the unoccupiable state means that the point is planned on the local path;

[0054] If the planned point is in an occupiable state, determine whether the associated point of the planned point is in an unoccupiable state; wherein the associated point is a point whose distance to the planned point is less than or equal to the maximum radius of the current mobile robot; that is, the associated point is a point that will be occupied when the current mobile robot passes through the planned point; if the associated point of the planned point is in an unoccupiable state, the planned point is adjusted to an unoccupiable state;

[0055] If the associated points of the planned points are in an occupiable state, it is determined whether the distance between the planned points and the adjacent points in an unoccupiable state is less than the distance that does not require obstacle avoidance, which is the sum of the maximum radius of the current mobile robot, the safety distance, and the maximum radius of the mobile robot occupying the adjacent points; if it is less than, the planned point is adjusted to an unoccupiable point; if it is greater than or equal to, the planned point is an occupiable point; specifically, the safety distance is a preset value based on actual needs, such as 10 to 20CM, that is, the distance at which two mobile robots can pass without interfering with each other or avoiding each other. Among them, the adjacent points are points between the maximum radius range of the current mobile robot and the preset limited range. In some optional embodiments, the limited range can be set to within twice the maximum radius of the largest mobile robot.

[0056] Specifically, if Figure 2 In one embodiment shown, the current mobile robot is at point 8, and point 2 is the planned point of the current mobile robot; the nearby mobile robot is at point 7, and its planned local path is point 6→9→10. Points 6, 9, and 10 are unoccupiable points. Among them, points 4 and 5 are both associated points of planned point 2, and points 6, 9, and 10 are all adjacent points of planned point 2. At this time, the current mobile robot first needs to determine whether planned point 2 is in an occupied state. If so, it then determines whether points 4 and 5 are in an occupied state. If so, it then determines whether the distance between planned point 2 and points 6, 9, and 10 is less than the distance that does not require obstacle avoidance. If not, planned point 2 can be occupied by the current mobile robot as a point on the local planned path.

[0057] Step S23: Select the planned points between the current point and the first planned point in an unoccupiable state as the local path of the current mobile robot.

[0058] In an embodiment of the present invention, when planning a local path, not only is the availability of the planned point ahead considered, but also the availability of its associated points. Only when both a planned point and its associated points are available can the planned point be occupied by the current mobile robot. This prevents large mobile robots from colliding with mobile robots at associated points when moving to a planned point. This allows mobile robots of different models to coexist in a facility, reducing the need for emergency braking and facilitating the transport of precision components such as silicon wafers and semiconductors.

[0059] Furthermore, even when both the planned point and its corresponding associated point are in an occupiable state, further consideration is given to whether there is sufficient safety distance between the planned point and any occupied adjacent mobile robots. Therefore, the system determines whether the distance between the planned point and an unoccupiable adjacent point is less than the obstacle avoidance distance, which is the sum of the current mobile robot's maximum radius, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point. Only when this distance is greater than or equal to the obstacle avoidance distance can the planned point be occupied by the current mobile robot. This effectively avoids the need for the current mobile robot to avoid the mobile robot occupying the adjacent point after moving to the planned point, minimizing the impact on other mobile robots and facilitating smooth material transportation.

[0060] Furthermore, after planning the local path of the current mobile robot, the planned points and their associated points in the local path of the current mobile robot are adjusted to an unoccupiable state. In this embodiment, by adjusting the planned points and their associated points in the local path of the current mobile robot to an unoccupiable state, subsequent mobile robots no longer plan these points when planning their local paths, thereby avoiding conflicts. It is worth noting that when a mobile robot moves forward one point, the previous point of the mobile robot is no longer in the local planned path, i.e., the previous point is released and the state of the previous point is adjusted to an occupiable state, allowing other mobile robots to preemptively occupy it.

[0061] Furthermore, after all mobile robots complete local path planning for the current frame, a local path is issued to each mobile robot, and local path planning for the next frame is performed. In this way, all mobile robots can drive along local paths, reducing the possibility of conflicts.

[0062] Preferably, when determining whether multiple planned points are in an unoccupiable state, each point is evaluated sequentially along its own global path, and the evaluation is terminated when one of the planned points is in an unoccupiable state. This embodiment uses sequential evaluation to quickly find the first planned point in the forward direction that is in an unoccupiable state. Once the first planned point in an unoccupiable state appears, the points after the locked point do not need to be evaluated, reducing the amount of computation.

[0063] Preferably, during local path planning, if a planned point is occupied by the same mobile robot for longer than a preset time, the planned point is identified as a congestion point. Using an improved A* algorithm, the path cost of the congestion point is adjusted to the maximum value, and a new global route is replanned. This allows the mobile robot to plan a new global path that bypasses the congestion point, achieving intelligent congestion resolution and enabling other mobile robots to bypass the congestion point.

[0064] Specifically, the task priority sequence includes the following steps;

[0065] Obtain the order in which the mobile robot receives the target, the final path length to the destination, and the number of turns along the path;

[0066] Calculate the task priority of each mobile robot using the following formula:

[0067] ;

[0068] in, is the task priority of the j-th mobile robot, It is a 0-1 decision variable, which is set to 1 when the end point is the machine point, and is set to 0 when the end point is the standby point or the charging point. It is the sum of all node distances from the starting point to the end point of the global path; is a 0-1 decision variable, traversing the global path n When the node passes through i When a node needs to be rotated, set it to 1, and when it does not need to be rotated, set it to 0. is the target machine waiting time; 、 、 are specific gravity respectively; 、 、 The value of can be set according to actual needs and is not specifically limited in the present invention.

[0069] Specifically, when all other conditions are the same, a task with a destination at a machine has a higher priority than a task with a destination at a standby point or charging point. This is to prioritize planning for mobile robots that need to perform tasks, while mobile robots that arrive at standby points or charging points can be relegated to later planning, thereby improving transportation efficiency. When all other conditions are the same, the longer the global path, the higher the task priority of the mobile robot, allowing the mobile robot to seize as many points as possible and reach the destination as quickly as possible. When all other conditions are the same, the more nodes that need to be rotated in the global path, the longer the time required for the mobile robot to complete the global path. In order for the mobile robot to reach the target as quickly as possible, the more nodes that need to be rotated in the global path, the higher the task priority. When all other conditions are the same, the longer the waiting time for the target machine, the more urgent it is for the current mobile robot to reach the target machine. Therefore, the longer the waiting time for the target machine, the higher the task priority.

[0070] The task priority calculation provided by the present invention comprehensively considers the type of endpoint, the sum of all node distances from the start point to the end point of the global path, the number of rotation nodes, and the waiting time of the target machine, making the task priority calculation comprehensive and reasonable.

[0071] Tasks are sorted by priority. If their priorities are equal, they are sorted by the order in which they were received. Tasks are sorted by priority. If their priorities are equal, they are sorted by the order in which they were received. That is, the mobile robot with the higher-priority task performs local path planning first. If their priorities are equal, the mobile robot that received the target task first performs local path planning first.

[0072] The second aspect of the present invention discloses a path planning device for collaborative transportation of multiple robots, comprising:

[0073] Global path planning module, used to plan the optimal global path points for all mobile robots;

[0074] The local path planning module is used to plan the local path of each mobile robot in the current frame in sequence according to the task priority. The local path planning module includes:

[0075] The local planning unit is used to obtain the current position of the mobile robot and plan several planned positions along its own global path starting from the current position;

[0076] A state judgment unit is used to judge whether the planned point is in an occupiable state or an unoccupiable state; the occupiable state is when the point is not planned on the local path, and the unoccupiable state is when the point is planned on the local path;

[0077] If the planned point is in an occupiable state, determine whether the associated point of the planned point is in an unoccupiable state; wherein the associated point is a point whose distance to the planned point is less than or equal to the maximum radius of the current mobile robot; that is, the associated point is a point that will be occupied when the current mobile robot passes through the planned point; if the associated point of the planned point is in an unoccupiable state, the planned point is adjusted to an unoccupiable state;

[0078] If the associated point of the planned point is in an occupiable state, then determine whether the distance between the planned point and the adjacent point in the unoccupiable state is less than the obstacle avoidance distance, where the obstacle avoidance distance is the sum of the maximum radius of the current mobile robot, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point; if less than, the planned point is adjusted to an unoccupiable point; if greater than or equal to, the planned point is an occupiable point;

[0079] The local path updating unit is used to select a planned point between the current point and the first planned point in an unoccupiable state as the local path of the current mobile robot.

[0080] Optionally, the local path planning module is further configured to adjust the planned points and associated points of the local path of the current mobile robot to an unoccupiable state after planning the local path of the current mobile robot.

[0081] Optionally, the state judgment unit judges each point in sequence along its own global path, and terminates the judgment when one of the planned points is in an unoccupiable state.

[0082] Furthermore, it also includes a sending module for sending a local path to each mobile robot after all mobile robots complete the local path planning of the current frame; and triggering the local path planning module to plan the local path planning of the next frame.

[0083] It should be noted that the multi-mobile robot scheduling device provided in the embodiments of the present invention can be installed on a server for centrally managing multiple mobile robots, and the various units and modules described above can refer to program modules or units. Further details and corresponding technical effects of the system of the embodiments of the present invention can be found in the description of the method embodiment above and will not be repeated here.

[0084] The system of the above-mentioned embodiment of the present invention can be used to execute the corresponding method embodiment of the present invention and accordingly achieve the technical effects achieved by the above-mentioned method embodiment of the present invention, which will not be described in detail here.

[0085] In the embodiment of the present invention, relevant functional modules can be implemented by a hardware processor.

[0086] like Figure 4 As shown, another aspect of the present invention discloses an electronic device 400 comprising: a processor 401 and a memory 402. The processor 401 and the memory 402 are connected, for example, via a bus 403. Furthermore, the electronic device 400 may also include a transceiver 404. It should be noted that in actual applications, there is not limited to one transceiver 404, and the structure of the electronic device 400 does not constitute a limitation on the embodiments of the present application. The processor 401 is used in the embodiments of the present application to implement the functions of the various units and modules of the path planning method for multi-robot collaborative transportation. The processor 401 may be a CPU, a general-purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. It may implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the present disclosure. The processor 401 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc. The bus 403 may include a path for transmitting information between the aforementioned components. The bus 403 may be a PCI bus or an EISA bus, for example. The bus 403 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 Indicated by only one thick line, it does not mean that there is only one bus or one type of bus. The memory 402 can be a ROM or other type of static storage device that can store static information and instructions, a RAM or other type of dynamic storage device that can store information and instructions, or an EEPROM, CD-ROM or other optical disk storage, optical disk storage (including compressed optical disk, laser disk, optical disk, digital versatile disk, Blu-ray disk, etc.), magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited to this. The memory 402 is used to store the application code for executing the solution of the present application, and is controlled by the processor 401 to execute. The processor 401 is used to execute the application code stored in the memory 402 to implement the path planning method for collaborative transportation of multiple robots provided by the present invention.

[0087] On the other hand, an embodiment of the present invention provides a storage medium having a computer program stored thereon, which is executed by a processor to perform the steps of the path planning method for multi-robot collaborative transportation as executed by the server above.

[0088] The above-mentioned product can execute the method provided in the embodiment of this application, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not fully described in this embodiment, please refer to the method provided in the embodiment of this application.

[0089] The above describes in detail the optional implementation methods of the embodiments of the present invention in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation methods. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the scope of protection of the embodiments of the present invention.

[0090] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0091] In addition, various implementations of the embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A path planning method for collaborative transportation of multiple robots, characterized by: include: Step S1: Plan the optimal global path points of all mobile robots; Step S2: Perform local path planning for each mobile robot in the current frame in order according to the task priority. The local path planning includes: Step S21: obtaining the current position of the current mobile robot, and planning a number of planned positions along its own global path starting from the current position; Step S22: Determine whether the planned point is in an occupiable state or an unoccupiable state; If the planned point is in an occupiable state, then determine whether the associated point of the planned point is in an unoccupiable state; wherein the associated point is a point whose distance to the planned point is less than or equal to the maximum radius of the current mobile robot; if the associated point of the planned point is in an unoccupiable state, then adjust the planned point to an unoccupiable state; If the associated point of the planned point is in an occupiable state, then determine whether the distance between the planned point and the adjacent point in the unoccupiable state is less than the obstacle avoidance distance, which is the sum of the maximum radius of the current mobile robot, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point; if it is less than, the planned point is adjusted to an unoccupiable point; if it is greater than or equal to, the planned point is an occupiable point; Step S23: Select the planned points between the current point and the first planned point in an unoccupiable state as the local path of the current mobile robot.

2. The path planning method for multi-robot collaborative transportation according to claim 1, characterized in that: Step S24: After planning the local path of the current mobile robot, the planned points of the local path of the current mobile robot and their associated points are adjusted to an unoccupiable state.

3. The path planning method for multi-robot collaborative transportation according to claim 1, characterized in that: Step S3: After all mobile robots complete the local path planning for the current frame, a local path is issued to each mobile robot; and the local path planning for the next frame is performed.

4. The path planning method for multi-robot collaborative transportation according to claim 1, characterized in that: In determining whether multiple planned points are in an unoccupiable state, each point is judged in turn along its own global path. The judgment is terminated when one of the planned points is in an unoccupiable state.

5. The path planning method for multi-robot collaborative transportation according to claim 1, characterized in that: In local path planning, when a planning point is occupied by the same mobile robot for more than a preset time, the planning point is determined to be a blocking point; Using the improved A* algorithm, the path cost of the congestion point is adjusted to the highest value, and a new global route is replanned.

6. The path planning method for multi-robot collaborative transportation according to claim 1, characterized in that: The task priority sequence includes the following steps; Obtain the order in which the mobile robot receives the target, the final path length to the destination, and the number of turns along the path; Calculate the task priority of each mobile robot using the following formula: ； in, is the task priority of the j-th mobile robot, It is a 0-1 decision variable, which is set to 1 when the end point is the machine point, and is set to 0 when the end point is the standby point or the charging point. It is the sum of all node distances from the starting point to the end point of the global path; is a 0-1 decision variable, traversing the global path n When the node passes through i When a node needs to be rotated, set it to 1, and when it does not need to be rotated, set it to 0. is the target machine waiting time; 、 、 are specific gravity respectively; Sort by task priority. If the task priorities are equal, arrange them in the order of receiving the target tasks.

7. A path planning device for collaborative transport of multiple robots, characterized by: include: Global path planning module, used to plan the optimal global path points for all mobile robots; The local path planning module is used to plan the local path of each mobile robot in the current frame in sequence according to the task priority. The local path planning module includes: The local planning unit is used to obtain the current position of the mobile robot and plan several planned positions along its own global path starting from the current position; A state judgment unit is used to judge whether the planned point is in an occupiable state or an unoccupiable state; If the planned point is in an occupiable state, then determine whether the associated point of the planned point is in an unoccupiable state; wherein the associated point is a point whose distance to the planned point is less than or equal to the maximum radius of the current mobile robot; if the associated point of the planned point is in an unoccupiable state, then adjust the planned point to an unoccupiable state; If the associated point of the planned point is in an occupiable state, then determine whether the distance between the planned point and the adjacent point in the unoccupiable state is less than the obstacle avoidance distance, where the obstacle avoidance distance is the sum of the maximum radius of the current mobile robot, the safety distance, and the maximum radius of the mobile robot occupying the adjacent point; if less than, the planned point is adjusted to an unoccupiable point; if greater than or equal to, the planned point is an occupiable point; The local path updating unit is used to select a planned point between the current point and the first planned point in an unoccupiable state as the local path of the current mobile robot.

8. The path planning device for multi-robot collaborative transportation according to claim 7, characterized in that: The local path planning module is also used to adjust the planned points of the local path of the current mobile robot and its associated points to an unoccupiable state after planning the local path of the current mobile robot.

9. The path planning device for multi-robot collaborative transportation according to claim 7, characterized in that: It also includes a sending module for sending a local path to each mobile robot after all mobile robots complete the local path planning of the current frame; and triggering the local path planning module to plan the local path planning of the next frame.

10. The path planning device for multi-robot collaborative transportation according to claim 7, characterized in that: The state judgment unit judges each point in turn along its own global path, and terminates the judgment when one of the planned points is in an unoccupiable state.

11. An electronic device, characterized in that: The method comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of claims 1 to 6 when executing the program.

12. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the method according to any one of claims 1 to 6.

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