Cooperative sorting method based on intelligent sorting robot

Abstract

The invention relates to the technical field of distribution network logistics management, and provides a collaborative sorting method based on an intelligent sorting robot, which enables the sorting robot to quickly and accurately identify the position of an article through the construction and updating of a three-dimensional warehouse map, thereby optimizing the sorting path, reducing the round-trip time in the transportation process, and improving the sorting efficiency. And the warehouse sorting efficiency is improved. According to the method, a plurality of sorting robots are allowed to work cooperatively, interaction among the sorting robots is preferentially considered, a loading path and a handover path are reasonably arranged, path conflicts are avoided, the path width is judged, and the sorting robots are reasonably arranged to pass, so that the passing efficiency is improved, congestion caused by staggering of the sorting robots is avoided, and the working efficiency is improved. The round-trip time in the transportation process is shortened, through planning the handover path, article handover and unified transportation between the sorting robots are achieved, the number of the sorting robots in the transportation process is reduced, and obstacles in the transportation process are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network logistics management, and in particular to a collaborative picking method based on an intelligent picking robot. Background Art

[0002] In the field of distribution network logistics, sorting tasks refer to the process of classifying, organizing and shipping items in the warehouse according to specific requirements. The logistics management of the distribution network involves the efficient classification and organization of power equipment, components and related materials. With the rapid development of smart grids, the demand for distribution network logistics has increased significantly, and the warehouse sorting workload has increased dramatically, which has put forward higher requirements for sorting efficiency, accuracy and cost control. Traditional sorting methods mainly rely on manual labor, and there are problems such as slow sorting speed, high error rate and high labor cost. Therefore, the optimized execution of sorting tasks has become a technical problem that needs to be solved urgently.

[0003] In order to optimize the execution of sorting tasks, it is necessary to use advanced technical means, such as automated sorting systems for optimization. The automated sorting system realizes the automatic identification and sorting of distribution network materials by introducing picking robots, conveyor belts and other equipment; however, in the sorting of distribution network materials, due to the large variety of distribution materials and the huge amount of temporary storage, in actual sorting, the operating capacity of a single picking robot is often limited, and it is difficult to meet the large-scale and efficient sorting needs. When multiple picking robots are used, there are problems such as uneven task distribution, mechanical collisions, and path conflicts.

[0004] Based on this, the present invention proposes a collaborative picking method based on an intelligent picking robot to reduce labor costs, improve work efficiency, and prevent problems such as uneven task distribution, mechanical collisions, and path conflicts when multiple picking robots are operating. Summary of the invention

[0005] The purpose of the present invention is to address the deficiencies of the prior art and to provide a collaborative picking method based on an intelligent picking robot to reduce labor costs, improve work efficiency, and prevent problems such as uneven task distribution, mechanical collisions, and path conflicts when multiple picking robots are operating.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A collaborative picking method based on an intelligent picking robot comprises the following steps:

[0008] Step 1: Obtain the item information of the warehouse and the point cloud data corresponding to each item, and build a 3D warehouse map based on the item information and point cloud data;

[0009] Step 2: Monitor objects in the warehouse and update the 3D warehouse map;

[0010] Step 3: Obtain the spatial position of the picking robot, map the spatial position of the picking robot onto the three-dimensional warehouse map, and obtain a real-time navigation map;

[0011] Step 4: After receiving the sorting task, extract the sorting items from the sorting task and determine the loading location of each sorting item according to the three-dimensional warehouse map;

[0012] Step 5: Plan the path for the picking robot to load items based on the loading location of each sorting item.

[0013] Preferably, the specific steps in step 5 are as follows:

[0014] Step 5.1: taking a moving path from one loading position to another loading position as a first path, and enclosing the first path to form a closed path;

[0015] Step 5.2: Extract the sorting area from the sorting task, and set the starting point and end point of the closed path according to the sorting area; obtain the unassigned picking robot closest to the starting point of the closed path, and plan the preparation path of the unassigned picking robot according to the spatial position of the unassigned picking robot and the starting point position of the closed path, that is, the unassigned picking robot moves from the current position to the starting point of the closed path; obtain the processing delay, the moving speed of the picking robot and the preparation path distance; wherein the processing delay refers to the difference between the planning start time, that is, the time when the sorting task is received, and the planning end time, that is, the time when the unassigned picking robot is about to start moving, that is, the processing delay = planning start time - planning end time; the preparation time of the unassigned picking robot is calculated by the preparation path distance and the moving speed of the picking robot;

[0016] Step 5.3: Obtain the distance of each first path in the closed path, and determine the starting point and the end point of each first path in sequence according to the connection order, and number each first path, and calculate the time period during which the unassigned picking robot passes through the first path in sequence according to the number; determine the first path;

[0017] Step 5.4: according to the number of first paths finally retained, a number of connected first paths are used as second paths; the number of picking robots performing the sorting operation is determined according to the number of second paths;

[0018] Step 5.5: Based on the starting point and end point of the first path, determine the starting point and end point of the second path; plan the handover path of the picking robot according to the end point of the second path; obtain the unassigned picking robot closest to the starting point of the second path, move the unassigned picking robot to the starting point of the second path, and then pass through each loading position in turn along the second path until it reaches the end point of the second path, and then move to the handover position along the handover path, gather the items, and transport them to the sorting area by one picking robot.

[0019] Preferably, the specific steps of step 5.3 are as follows:

[0020] Step 5.3.1: Calculate the time t1 when the unassigned picking robot moves to the starting point of the first path by the sum of the preparation time and the planning end time of the unassigned picking robot; calculate the moving time of the unassigned picking robot in the first path by the product of the first path distance and the moving speed of the picking robot, and calculate the time t2 when the unassigned picking robot moves to the end point of the first path according to the sum of the moving time and time t1;

[0021] Step 5.3.1-1: Obtain the assigned picking robots that pass through the first path to perform other sorting tasks between time t1 and t2;

[0022] Step 5.3.1-11: If the assigned picking robot is not obtained, the first path is retained;

[0023] Step 5.3.1-12: If an assigned picking robot is obtained, determine whether there is an intersection between the assigned picking robot and the unassigned picking robot on the first path;

[0024] Step 5.3.1-121: If there is an intersection, obtain the width of the first path, and determine whether the width of the first path is greater than twice the width of the picking robot;

[0025] If the width of the first path is more than twice the width of the picking robot, that is, two picking robots are allowed to pass side by side, the first path is retained;

[0026] If the width of the first path is less than or equal to twice the width of the picking robot, that is, only a single picking robot is allowed to pass, the first path is deleted;

[0027] Step 5.3.1-122: If there is no intersection, retain the first path;

[0028] Step 5.3.2: While retaining the first path, use the following method:

[0029] The time t1 when the unassigned picking robot moves to the end point of the previous numbered first path is used as the time t3 when the current numbered first path starts;

[0030] The moving time of the unassigned picking robot on the first path is calculated by multiplying the distance of the first path with the moving speed of the picking robot. The time t4 when the unassigned picking robot moves to the end point of the first path is calculated based on the sum of the moving time and the time t3.

[0031] Step 5.3.2-1: Obtain the assigned picking robots that pass through the first path to perform other sorting tasks between time t3 and t4;

[0032] Using steps 5.3.1-11 to 5.3.1-122, determine whether to retain the first path;

[0033] Step 5.3.3: In the case of deleting the first path, use the following method:

[0034] Obtain the unassigned picking robot closest to the starting point of the next numbered first path, and plan the preparation path of the unassigned picking robot according to the spatial position of the unassigned picking robot and the starting point position of the first path, that is, the unassigned picking robot moves from the current position to the starting point of the first path; calculate the preparation time of the unassigned picking robot according to the preparation path distance and the moving speed of the picking robot;

[0035] Using steps 5.3.1 to 5.3.1-122, determine whether to retain the first path;

[0036] After traversing all first paths in the closed path, the retained first path is obtained.

[0037] Preferably, in step 5.5, according to the end position of the second path, the carrier positions on several second paths that are close to each other and close to the sorting area are used to plan the handover path of the picking robot according to the end position of the second path.

[0038] Preferably, the handover path is a path that has the shortest sum of time to pass through a number of handover positions of loading and picking robots along the second path.

[0039] Preferably, in step 1, the article information is obtained through electronic tags of distribution network materials, and the distribution network material information is loaded onto the three-dimensional warehouse map.

[0040] Preferably, in step 2, if the object moves, point cloud data of the object before and after the movement is obtained, and the point cloud data before the movement of the object is replaced with the point cloud data after the movement to achieve real-time updating of the three-dimensional warehouse map, and the objects are shelves and obstacles.

[0041] Preferably, there are usually multiple sorting items in the sorting task in step 4. In order to speed up the sorting efficiency, a picking robot needs to reduce the round-trip time of item transportation and can transport multiple items at one time.

[0042] Preferably, in step 1, a laser radar is used to obtain point cloud data of each corner in the warehouse to construct a three-dimensional warehouse map.

[0043] The present invention discloses a collaborative picking method based on an intelligent picking robot, which has the following beneficial effects.

[0044] The present invention enables the picking robot to quickly and accurately identify the location of items through the construction and update of a three-dimensional warehouse map, thereby optimizing the picking path, reducing the round-trip time during transportation, and improving the efficiency of warehouse picking. The method allows multiple picking robots to work together, gives priority to the interaction between picking robots, reasonably arranges the loading path and the handover path, avoids path conflicts, and reasonably arranges the passage of picking robots by judging the width of the path, thereby improving the passage efficiency, avoiding congestion caused by the staggered picking robots, reducing the round-trip time during transportation, and realizing the handover and unified transportation of items between picking robots by planning the handover path, reducing the number of picking robots during transportation, and reducing obstacles during transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a flow chart of the collaborative picking method based on the intelligent picking robot of the present invention.

[0046] Figure 2 Schematic diagram of the distribution of picking robots in an embodiment of the present invention.

[0047] Figure 3 Schematic diagram of closed path combination in an embodiment of the present invention.

[0048] Figure 4 This is a distribution diagram of the assigned picking robots at a certain moment from time t1 to t2 in an embodiment of the present invention.

[0049] Figure 5 This is a distribution diagram of the assigned picking robots at a certain moment from time t3 to t4 in an embodiment of the present invention.

[0050] Figure 6 This is a distribution diagram of the assigned picking robots at a certain moment from time t5 to t6 in an embodiment of the present invention.

[0051] Figure 7 Schematic diagram of closed path combination in an embodiment of the present invention.

[0052] Figure 8 Schematic diagram of the handover path in an embodiment of the present invention. DETAILED DESCRIPTION

[0053] In order to explain in detail the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0054] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.

[0055] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0056] In the description of this application, the term "and / or" is an expression used to describe the logical relationship between objects, indicating that three relationships may exist, for example, A and / or B, which means: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this article generally indicates that the objects before and after are in an "or" logical relationship.

[0057] Without further limitations, in this application, the words "include", "comprises", "has" or other similar expressions used in the sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those limited elements, but also other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0058] Unless otherwise expressly specified or limited, in the description of the embodiments of the present application, the terms such as "install", "connect", "connect", "fix", "set", etc. used should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or an integrated setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For technicians in the technical field to which the present application belongs, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0059] Example

[0060] Please refer to Figure 1 , a collaborative picking method based on an intelligent picking robot, comprising the following steps:

[0061] Step 1: Obtain the item information of the warehouse and the point cloud data corresponding to each item, and build a 3D warehouse map based on the item information and point cloud data;

[0062] As a priority, in this implementation, laser radar is used in step 1 to obtain point cloud data of each corner in the warehouse and construct a three-dimensional warehouse map. In step 1, the item information is obtained through the electronic tag of the distribution network material, and the distribution network material information is loaded on the three-dimensional warehouse map.

[0063] Step 2: Monitor objects in the warehouse and update the 3D warehouse map;

[0064] As a priority, in this implementation, in step 2, if the object moves, the point cloud data of the object before and after the movement is obtained, and the point cloud data before the movement of the object is replaced with the point cloud data after the movement, so as to realize the real-time update of the three-dimensional warehouse map, where the objects are shelves and obstacles.

[0065] Step 3: Obtain the spatial position of the picking robot, map the spatial position of the picking robot onto the three-dimensional warehouse map, and obtain a real-time navigation map; each picking robot is equipped with a positioning device, and the positioning device can be any one of the existing technologies that can meet the positioning accuracy;

[0066] Step 4: After receiving the sorting task, extract the sorting items from the sorting task and determine the loading location of each sorting item according to the three-dimensional warehouse map;

[0067] As a priority, in this implementation, there are usually multiple sorting items in the sorting task in step 4. In order to speed up the sorting efficiency, a picking robot needs to reduce the round-trip time of item transportation and can transport multiple items at one time.

[0068] Specifically, when the warehouse receives the first sorting task, the system will automatically extract a list of items to be sorted from the first sorting task (the sorting items are A, B, C, D, E, F), and quickly determine the loading position of each sorted item according to the three-dimensional warehouse map (respectively: A (Xa, Ya), B (Xb, Yb), C (Xc, Yc), D (Xd, Yd), E (Xe, Ye), F (Xf, Yf)). In order to improve the sorting efficiency, multiple items need to be loaded so that the picking robot can transport multiple items to the sorting area (Xn, Yn) at one time, thereby reducing the round-trip time for transporting items.

[0069] Step 5: Plan the path for the picking robot to load items based on the loading location of each sorting item.

[0070] As a priority, in this implementation, the specific steps in step 5 are as follows:

[0071] Step 5.1: taking a moving path from one loading position to another loading position as a first path, and enclosing the first path to form a closed path;

[0072] As an example, in this embodiment, according to the loading positions of the articles, a moving path from one loading position to another loading position with the shortest distance, that is, a first path, is planned. The specific steps are as follows:

[0073] Choose any item as the starting point. In this example, A is the starting point. Figure 2 , use the following formula to calculate the moving distance from A to B, C, D, E, and F respectively, and get the objects B and C closest to A;

[0074] S = |(Xa-Xi)+(Ya-Yi)|, where S represents the moving distance from A to B, C, D, E, and F, respectively, and Xi represents the loading position of B, C, D, E, or F;

[0075] Based on the calculated objects B and C closest to A, use S = |(Xb-Xi) + (Yb-Yi)| to calculate the moving distance from B to C, D, E, and F, and use S = |(Xc-Xi) + (Yc-Yi)| to calculate the moving distance from C to B, D, E, and F, and get the object D closest to B and C; and so on, based on the object D closest to B and C, use S = |(Xd-Xi) + (Yd-Yi)| to calculate the moving distance from D to E and F, and get the object E closest to D; therefore, the closed path combination obtained includes Figure 3 and Figure 7 Two, choose one of them as the planned route; this embodiment chooses Figure 2 The closed path is used as the planned route;

[0076] Step 5.2: Extract the sorting area from the sorting task, and set the starting point and end point of the closed path according to the sorting area; obtain the unassigned picking robot closest to the starting point of the closed path, and plan the preparation path of the unassigned picking robot according to the spatial position of the unassigned picking robot and the starting point position of the closed path, that is, the unassigned picking robot moves from the current position to the starting point of the closed path; obtain the processing delay, the moving speed of the picking robot and the preparation path distance; wherein the processing delay refers to the difference between the planning start time, that is, the time when the sorting task is received, and the planning end time, that is, the time when the unassigned picking robot is about to start moving, that is, the processing delay = planning start time - planning end time; the preparation time of the unassigned picking robot is calculated by the preparation path distance and the moving speed of the picking robot;

[0077] Step 5.3: Obtain the distance of each first path in the closed path, and determine the starting point and the end point of each first path in sequence according to the connection order, and number each first path, and calculate the time period during which the unassigned picking robot passes through the first path in sequence according to the number; determine the first path;

[0078] As a priority, in this implementation, the specific steps of step 5.3 are as follows:

[0079] Step 5.3.1: Calculate the time t1 when the unassigned picking robot moves to the starting point of the first path by the sum of the preparation time and the planning end time of the unassigned picking robot; calculate the moving time of the unassigned picking robot in the first path by the product of the first path distance and the moving speed of the picking robot, and calculate the time t2 when the unassigned picking robot moves to the end point of the first path according to the sum of the moving time and time t1;

[0080] Step 5.3.1-1: Obtain the assigned picking robots that pass through the first path to perform other sorting tasks between time t1 and t2;

[0081] Step 5.3.1-11: If the assigned picking robot is not obtained, the first path is retained;

[0082] Step 5.3.1-12: If an assigned picking robot is obtained, determine whether there is an intersection between the assigned picking robot and the unassigned picking robot on the first path;

[0083] Step 5.3.1-121: If there is an intersection, obtain the width of the first path, and determine whether the width of the first path is greater than twice the width of the picking robot;

[0084] If the width of the first path is more than twice the width of the picking robot, that is, two picking robots are allowed to pass side by side, the first path is retained;

[0085] If the width of the first path is less than or equal to twice the width of the picking robot, that is, only a single picking robot is allowed to pass, the first path is deleted;

[0086] Step 5.3.1-122: If there is no intersection, retain the first path;

[0087] Step 5.3.2: While retaining the first path, use the following method:

[0088] The time t1 when the unassigned picking robot moves to the end point of the previous numbered first path is used as the time t3 when the current numbered first path starts;

[0089] The moving time of the unassigned picking robot on the first path is calculated by multiplying the distance of the first path with the moving speed of the picking robot. The time t4 when the unassigned picking robot moves to the end point of the first path is calculated based on the sum of the moving time and the time t3.

[0090] Step 5.3.2-1: Obtain the assigned picking robots that pass through the first path to perform other sorting tasks between time t3 and t4;

[0091] Using steps 5.3.1-11 to 5.3.1-122, determine whether to retain the first path;

[0092] Step 5.3.3: In the case of deleting the first path, use the following method:

[0093] Obtain the unassigned picking robot closest to the starting point of the next numbered first path, and plan the preparation path of the unassigned picking robot according to the spatial position of the unassigned picking robot and the starting point position of the first path, that is, the unassigned picking robot moves from the current position to the starting point of the first path; calculate the preparation time of the unassigned picking robot according to the preparation path distance and the moving speed of the picking robot;

[0094] Using steps 5.3.1 to 5.3.1-122, determine whether to retain the first path;

[0095] After traversing all first paths in the closed path, the retained first path is obtained.

[0096] As an example, in this embodiment, Figure 4 represents the distribution diagram of the assigned picking robots at a certain time from time t1 to t2. If there is no assigned picking robot on the first path EF at time t1 to t2, the first path EF is retained;

[0097] Determine whether to keep the first path DE, the steps are as follows:

[0098] Get the assigned picking robots that pass through the first path DE at time t3-t4, such as Figure 5 As shown, Figure 5 represents the distribution diagram of the assigned picking robots at a certain time from time t3 to t4; Figure 5 It can be seen that at time t3-t4, there is an assigned picking robot on the first path DE, and it is determined whether there is an intersection between the assigned picking robot and the unassigned picking robot on the first path DE (the calculation formula can be used: Assume that the initial position of the assigned picking robot is x01, the velocity vector is v01, and the initial position of the unassigned picking robot is x02, the velocity vector is

[0099] v02; x01+v01*t=x02+v02*t, find the intersection time t. If the intersection time t is within t3~t4, there is an intersection; otherwise, there is no intersection)

[0100] Depend on Figure 5 It can be seen that the assigned picking robot and the unassigned picking robot have an intersection on the first path DE, and the width of the first path DE only allows a single picking robot to pass through, so the first path DE is deleted;

[0101] To determine whether to keep the first path CD, follow these steps:

[0102] Obtain the unassigned picking robot 2 closest to the starting point of the first path CD, and plan the preparation path of the unassigned picking robot (i.e., the unassigned picking robot moves from the current position to the starting point of the first path CD) according to the spatial position of the unassigned picking robot 2 and the position of the starting point D of the first path CD; calculate the preparation time of the unassigned picking robot 2 by the preparation path distance and the moving speed of the picking robot;

[0103] The time t5 when the unassigned picking robot 2 moves to the starting point of the first path is calculated by the sum of the preparation time of the unassigned picking robot 2 and the planning end time;

[0104] The moving time of the unassigned picking robot 2 on the first path CD is calculated by multiplying the distance of the first path CD and the moving speed of the picking robot. The time t6 when the unassigned picking robot 2 moves to the end point of the first path CD is calculated based on the sum of the moving time and the time t5.

[0105] Get the assigned picking robots that pass through the first path CD at time t5-t6, such as Figure 6 As shown, Figure 6 represents the distribution diagram of the assigned picking robots at a certain time from time t5 to t6; Figure 6 It can be seen that at time t5-t6, there is an assigned picking robot on the first path CD, and it is determined whether there is an intersection between the assigned picking robot and the unassigned picking robot on the first path CD (the inference steps are the same as above, and no inference is performed here), by Figure 6 It can be seen that there is no intersection between the assigned picking robot and the unassigned picking robot on the first path CD, and the first path CD is retained;

[0106] Then determine in sequence whether to retain the first path BC and the first path AB, the steps are the same as above, and are not listed one by one. In this embodiment, the first paths AB, BC, CD, and EF are retained, wherein the first paths AB, BC, and CD are connected.

[0107] Step 5.4: according to the number of first paths finally retained, a number of connected first paths are used as second paths; the number of picking robots performing the sorting operation is determined according to the number of second paths;

[0108] The connected first paths are used as the second paths (i.e., there are two second paths, the second path 1 is composed of the first paths AB, BC, and CD, and the second path 2 is composed of the first path EF); the number of picking robots performing the sorting operation is determined according to the number of the second paths (i.e., two picking robots (the first picking robot and the second picking robot) are used to collaboratively complete the sorting operation);

[0109] Step 5.5: Based on the starting point and end point of the first path, determine the starting point and end point of the second path; plan the handover path of the picking robot according to the end point of the second path; obtain the unassigned picking robot closest to the starting point of the second path, move the unassigned picking robot to the starting point of the second path, and then pass through each loading position in turn along the second path until it reaches the end point of the second path, and then move to the handover position along the handover path, gather the items, and transport them to the sorting area by one picking robot.

[0110] As a priority, in this implementation, in step 5.5, according to the end position of the second path, for a number of carrier positions close to the sorting area on the second path, the handover path of the picking robot is planned according to the end position of the second path. In this implementation, the handover path is the path with the shortest sum of the time of loading the handover positions of the picking robots along the second path.

[0111] As an example, the endpoints of the two second paths are obtained (i.e., A and D of the second path 1, and E and F of the second path 2), the starting point of the first path is used as the starting point of the second path (i.e., D and F), and the end point of the first path is used as the end point of the second path (i.e., A and E); according to the carrier positions of A and E, the handover position is determined. Specifically, since there is an intersection between the assigned picking robot and the unassigned picking robot on the first path DE, and the width of the first path only allows a single picking robot to pass, the handover cannot be achieved on the first path DE, and the route needs to be changed; when D is close to the sorting area, the nearest route is as follows Figure 8 As shown in FIG. 1 , since one of the routes has an assigned picking robot and the width of the route only allows a single picking robot to pass, the handover cannot be achieved on this route. Although the other route has an assigned picking robot, the width of the route allows two picking robots to pass side by side, so the handover can be achieved on this route. The handover position is located on this route. This route is used as the handover path of the first picking robot to obtain handover path 1. The handover path of the second picking robot is the shortest route from E to this route. Figure 8 As shown, the handover path 2 is obtained;

[0112] Since there are two handover paths 2, a reasonable handover path 2 is selected by calculating the time it takes for the first picking robot and the second picking robot to move to the handover position. For example: if the first picking robot and the second picking robot complete loading at the same time (i.e., arrive at the destination at the same time and start transportation), the time it takes for the first picking robot to move from D to handover position 1 is 1 second, and the time it takes to move to handover position 2 is 2 seconds. The time it takes for the second picking robot to move from E to handover position 1 is 2 seconds, and the time it takes to move to handover position 2 is 2.5 seconds. The time difference when arriving at handover position 1 is ΔT1=2-1=1, and the time difference when arriving at handover position 2 is ΔT2=2.5-2=0.5, ΔT1>ΔT2, so handover position 2 is selected as the final handover position, thereby determining the final handover path (the handover path passes through the final handover position). Obtain the unassigned picking robot closest to the starting point of the second path, move the unassigned picking robot to the starting point of the second path, and combine Figure 2 , that is, the picking robot 1 and the picking robot 3, plan the third path according to the spatial position of the unassigned picking robot and the starting point position of the second path, that is, the picking robot 1 moves from the current position to the starting point of the second path 1--A, and the picking robot 3 moves from the current position to the starting point of the second path 2--F; then, the picking robot 1 passes through A, B, C, and D along the second path 1 in sequence, and the picking robot 3 passes through F and E along the second path 2 in sequence; then, it moves to the handover position along the handover path, and the picking robot 1 hands over the items to the picking robot 3, which transports the items to the sorting area, and after arriving at the sorting area, places the items in the sorting area. As an option, in this embodiment, in order to avoid the existence of unassigned picking robots on the loading path, sorting tasks can be preferentially assigned to the unassigned picking robots on the loading path.

[0113] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The substitution may be a substitution of a part of the structure, device, method step, or a complete technical solution. The equivalent replacement or change according to the technical solution and the inventive concept of the present invention shall be covered within the protection scope of the present invention.

Claims

1. A collaborative picking method based on an intelligent picking robot, characterized in that: The following steps are involved: Step 1: Obtain the item information of the warehouse and the point cloud data corresponding to each item, and build a 3D warehouse map based on the item information and point cloud data; Step 2: Monitor objects in the warehouse and update the 3D warehouse map; Step 3: Obtain the spatial position of the picking robot, map the spatial position of the picking robot onto the three-dimensional warehouse map, and obtain a real-time navigation map; Step 4: After receiving the sorting task, extract the sorting items from the sorting task and determine the loading location of each sorting item according to the three-dimensional warehouse map; Step 5: Plan the path for the picking robot to load items based on the loading location of each sorting item.

2. The collaborative picking method based on the intelligent picking robot according to claim 1, characterized in that: The specific steps in step 5 are as follows: Step 5.1: taking a moving path from one loading position to another loading position as a first path, and enclosing the first path to form a closed path; Step 5.2: Extract the sorting area from the sorting task, and set the starting point and end point of the closed path according to the sorting area; Obtain the unassigned picking robot closest to the starting point of the closed path, and plan the preparation path of the unassigned picking robot according to the spatial position of the unassigned picking robot and the starting point position of the closed path, that is, the unassigned picking robot moves from the current position to the starting point of the closed path; obtain the processing delay, the moving speed of the picking robot and the preparation path distance; wherein, the processing delay refers to the difference between the planning start time, that is, the time when the sorting task is received, and the planning end time, that is, the time when the unassigned picking robot is about to start moving, that is, the processing delay = planning start time - planning end time; calculate the preparation time of the unassigned picking robot by the preparation path distance and the moving speed of the picking robot; Step 5.3: Obtain the distance of each first path in the closed path, and determine the starting point and the end point of each first path in sequence according to the connection order, and number each first path, and calculate the time period during which the unassigned picking robot passes through the first path in sequence according to the number; determine the first path; Step 5.4: according to the number of first paths finally retained, a number of connected first paths are used as second paths; the number of picking robots performing the sorting operation is determined according to the number of second paths; Step 5.5: Based on the starting point and end point of the first path, determine the starting point and end point of the second path; plan the handover path of the picking robot according to the end point of the second path; obtain the unassigned picking robot closest to the starting point of the second path, move the unassigned picking robot to the starting point of the second path, and then pass through each loading position in turn along the second path until it reaches the end point of the second path, and then move to the handover position along the handover path, gather the items, and transport them to the sorting area by one picking robot.

3. The collaborative picking method based on the intelligent picking robot according to claim 2, characterized in that: The specific steps of step 5.3 are as follows: Step 5.3.1: Calculate the time t1 when the unassigned picking robot moves to the starting point of the first path by the sum of the preparation time and the planning end time of the unassigned picking robot; calculate the moving time of the unassigned picking robot in the first path by the product of the first path distance and the moving speed of the picking robot, and calculate the time t2 when the unassigned picking robot moves to the end point of the first path according to the sum of the moving time and time t1; Step 5.3.1-1: Obtain the assigned picking robots that pass through the first path to perform other sorting tasks between time t1 and t2; Step 5.3.1-11: If the assigned picking robot is not obtained, the first path is retained; Step 5.3.1-12: If an assigned picking robot is obtained, determine whether there is an intersection between the assigned picking robot and the unassigned picking robot on the first path; Step 5.3.1-121: If there is an intersection, obtain the width of the first path, and determine whether the width of the first path is greater than twice the width of the picking robot; If the width of the first path is more than twice the width of the picking robot, that is, two picking robots are allowed to pass side by side, the first path is retained; If the width of the first path is less than or equal to twice the width of the picking robot, that is, only a single picking robot is allowed to pass, the first path is deleted; Step 5.3.1-122: If there is no intersection, retain the first path; Step 5.3.2: While retaining the first path, use the following method: The time t1 when the unassigned picking robot moves to the end point of the previous numbered first path is used as the time t3 when the current numbered first path starts; The moving time of the unassigned picking robot on the first path is calculated by multiplying the distance of the first path with the moving speed of the picking robot. The time t4 when the unassigned picking robot moves to the end point of the first path is calculated based on the sum of the moving time and the time t3. Step 5.3.2-1: Obtain the assigned picking robots that pass through the first path to perform other sorting tasks between time t3 and t4; Using steps 5.3.1-11 to 5.3.1-122, determine whether to retain the first path; Step 5.3.3: In the case of deleting the first path, use the following method: Obtain the unassigned picking robot closest to the starting point of the next numbered first path, and plan the preparation path of the unassigned picking robot according to the spatial position of the unassigned picking robot and the starting point position of the first path, that is, the unassigned picking robot moves from the current position to the starting point of the first path; calculate the preparation time of the unassigned picking robot according to the preparation path distance and the moving speed of the picking robot; Using steps 5.3.1 to 5.3.1-122, determine whether to retain the first path; After traversing all first paths in the closed path, the retained first path is obtained.

4. The collaborative picking method based on the intelligent picking robot according to claim 2, characterized in that: In step 5.5, according to the end position of the second path, for the carrier positions that are close to each other and close to the sorting area on several second paths, the handover path of the picking robot is planned according to the end position of the second path.

5. The collaborative picking method based on the intelligent picking robot according to claim 4, characterized in that: The handover path is a path that passes through a number of handover positions of loading and picking robots along the second path with the shortest sum of time.

6. The collaborative picking method based on the intelligent picking robot according to claim 1, characterized in that: In the step 1, the item information is obtained through the electronic tags of the distribution network materials, and the distribution network material information is loaded onto the three-dimensional warehouse map.

7. The collaborative picking method based on the intelligent picking robot according to claim 1, characterized in that: In step 2, if the object moves, the point cloud data of the object before and after the movement is obtained, and the point cloud data before the object moves is replaced with the point cloud data after the movement to achieve real-time update of the three-dimensional warehouse map, and the objects are shelves and obstacles.

8. The collaborative picking method based on the intelligent picking robot according to claim 1, characterized in that: There are usually multiple sorting items in the sorting task in step 4. In order to speed up the sorting efficiency, a picking robot needs to reduce the round-trip time of item transportation and can transport multiple items at one time.

9. The collaborative picking method based on the intelligent picking robot according to claim 1, characterized in that: In step 1, a laser radar is used to obtain point cloud data of each corner in the warehouse to construct a three-dimensional warehouse map.

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