A pallet stacking method for a transport robot, an electronic device, and a storage medium

Abstract

The present application provides a method for stacking pallets by a transport robot, an electronic device, and a storage medium, including dispatching a transport cart to transport an empty pallet in response to a stacking instruction; selecting a target stacking position, determining the stacking height or number of layers according to the current height or number of layers of the target stacking position, and controlling the transport cart to transport the empty pallet to the target stacking position for stacking; at the same stacking position, if a transport cart that responds to a later stacking instruction arrives at the target stacking position first, the stacking height or number of layers that should have arrived at the transport cart is exchanged with the transport cart that arrived first. The present application enables the transport cart that arrives first to put down the empty pallet and leave first, preventing the situation where the vehicle that arrives first cannot place the empty pallet and needs to carry the empty pallet and wait.

Description

Technical Field

[0001] The present application relates to the technical field of warehousing equipment, and in particular to a method for stacking pallets using a transport robot, an electronic device, and a storage medium. Background Art

[0002] AGVs (Automated Guided Vehicles), also known as unmanned guided vehicles, automated guided vehicles, and laser-guided vehicles, are characterized by their unmanned operation. AGVs are equipped with an automatic guidance system that ensures they can autonomously travel along a predetermined route without the need for human piloting, transporting goods or materials from their starting point to their destination.

[0003] In the existing technology, goods are generally placed on pallets, and AGVs carry goods by forking pallets. However, during the frequent entry and exit of goods, many empty pallets are generated, especially during picking and outbound delivery. As the goods are picked and placed in order boxes for packaging and outbound delivery, many empty pallets are scattered and stacked in a disorderly manner. Summary of the Invention

[0004] In response to the above-mentioned problems, the present application provides a pallet stacking method for a transport robot, an electronic device, and a storage medium, which can perform the task of stacking empty pallets in the intervals between performing transport tasks.

[0005] In a first aspect, the present application provides a pallet stacking method for a transport robot, for stacking empty pallets into a pallet stack, the method comprising:

[0006] In response to the stacking instruction, dispatch a transport vehicle to transport the empty pallet; select a target stacking position, determine the stacking height or number of layers according to the current height or number of layers of the target stacking position, and control the transport vehicle to transport the empty pallet to the target stacking position for stacking;

[0007] At the same stacking position, if the transport trolley that responds to the subsequent stacking instruction arrives at the target stacking position first, the stacking height or number of layers that should have arrived at the transport trolley will be exchanged with the transport trolley that arrived first.

[0008] In one embodiment, the dispatching of a transport vehicle to transport the empty pallet includes selecting an idle vehicle to transport the empty pallet.

[0009] Select the idle trolley with the closest driving distance to the location where the empty pallets are to be stacked as the target transport trolley to transport the empty pallets.

[0010] In one embodiment, the dispatching of a transport vehicle to transport the empty pallet includes selecting an idle vehicle to transport the empty pallet.

[0011] If there are multiple idle carts, one of them is selected as the first idle cart, and the travel distances of other idle carts to the empty pallet to be stacked are compared. If a second idle cart appears with a travel distance closer than that of the first idle cart, the travel distances of the remaining idle carts to the empty pallet to be stacked are compared with the travel distance of the second idle cart to the empty pallet to be stacked, until no idle cart appears with a travel distance closer than that of the Nth idle cart to the empty pallet to be stacked, then the Nth idle cart is selected as the target transport cart to transport the empty pallet.

[0012] In one embodiment, selecting a target stacking position includes:

[0013] For the stacking instruction, a stacking position with the smallest current pallet height or number of layers is selected as a target stacking position.

[0014] In one embodiment, selecting a target stacking position includes:

[0015] For the stacking instruction, a stacking position with the largest current pallet height or number of layers is selected as a target stacking position.

[0016] In one embodiment, the current pallet height or number of layers includes the height or number of layers of the pallet that has been placed on the stacking position, or includes the stacking height or number of layers obtained by adding the height or number of layers in the stacking instruction with the stacking position as the target stacking position.

[0017] In one embodiment, the pallet stacking method further includes: adding the height or number of layers of the pallets to be stacked in the stacking instruction to the target stacking position, and updating the current stacking height or number of layers of the target stacking position.

[0018] In one embodiment, the method includes, after the transport cart arrives at the target stacking position, determining whether the actual occupancy situation on the stacking position is consistent with the stacking height or number of layers of the transport cart, and if so, executing the stacking action; if not, determining the transport cart that should execute the stacking height or number of layers based on the actual occupancy situation of the target stacking position, and exchanging the stacking height or number of layers of the two transport carts.

[0019] In one embodiment, the selection of the target stacking position includes: obtaining the height or number of layers of the pallets to be stacked in the stacking instruction, and selecting the stacking position with the smallest or largest current pallet height or number of layers as the target stacking position for the stacking instruction. The target stacking position must satisfy the current height or number of layers plus the height or number of layers of the pallets to be stacked in the stacking instruction, which does not exceed the preset height or number of layers of the stacking position.

[0020] In one embodiment, the method includes exchanging the stacking height or number of layers that should currently arrive at the transport cart with the transport cart that arrives first, updating the current height or number of layers of the stacking position, and updating the remaining stacking heights or numbers of layers that have not arrived at the transport cart based on the updated current height or number of layers of the stacking position.

[0021] This is equivalent to exchanging the stacking height or number of layers of the current transport cart that is due to arrive with the transport cart that arrived earlier, updating the current height or number of layers of the stacking position, and then eliminating the task of the transport cart that arrived earlier, and then updating the tasks of all remaining transport carts that have not arrived. Here, the remaining transport carts that have not arrived include the transport carts that are due to arrive.

[0022] In one embodiment, the method comprises:

[0023] The stacking height or number of layers of the current transport cart that should arrive is exchanged with the transport cart that arrived first. The remaining transport carts that have not arrived are still in the order of the generation of the stacking instructions as the arrival order. The stacking height or number of layers of the transport carts are updated in sequence according to the updated current height or number of layers of the stacking position; or

[0024] The stacking height or number of layers of the current transport trolley that is due to arrive is exchanged with the transport trolley that arrived earlier, and the arrival order of the transport trolley that arrived earlier is returned to the current transport trolley that is due to arrive, and the arrival order of other transport trolleys remains unchanged.

[0025] The stacking height or number of layers of the current transport trolley that is due to arrive is exchanged with the transport trolley that arrives first, which is equivalent to the stacking instruction of the transport trolley that arrives first being completed ahead of its original stacking order. The arrival order of all remaining transport trolleys that have not arrived is still determined in the order in which the stacking instructions are generated, and the stacking height or number of layers of the transport trolleys are updated in turn; or, the stacking order of the current transport trolley that is due to arrive is exchanged with the transport trolley that arrives first, and the arrival order of other transport trolleys that have not arrived remains unchanged.

[0026] In one embodiment, exchanging the stack height or number of layers of the pallet that is currently due to arrive at the transport trolley with the transport trolley that arrives earlier includes:

[0027] The current transport cart that is due to arrive exchanges its task order with the transport cart that arrived earlier, while the order of the remaining transport carts that have not arrived remains unchanged. The remaining transport carts that have not arrived here do not include the current transport cart that is due to arrive, because the new order of the current transport cart that is due to arrive has been determined, and its new order of arrival is the original order of the transport cart that arrived earlier.

[0028] Alternatively, the stacking height or number of layers of the current transport cart that is due to arrive is swapped with the transport cart that arrived earlier, and the remaining transport carts that have not arrived are still determined in the order of the stacking instructions. The remaining transport carts that have not arrived here include the current transport cart that is due to arrive, because only the stacking order, or stacking height or number of layers of the current transport cart that is due to arrive is given to the transport cart that arrived earlier. The transport cart that is due to arrive now is still the one that arrived earlier. In principle, the order of the first transport cart that is due to arrive remains unchanged, but the transport cart that arrived earlier cuts in line and completes the stacking.

[0029] In one embodiment, the stacking position is provided with a preset height or number of layers. When the current stacking height or number of layers reaches the preset height or number of layers, the stacking position is set to a state that cannot be used as a target stacking position. When the actual occupied height or number of layers of the stacking position that cannot be used as a target stacking position reaches the preset height or number of layers, a transport trolley is dispatched to move the stacked pallet away from the stacking position, and the stacking position resumes the state of being usable as a target stacking position.

[0030] The third aspect of the present application provides an electronic device, comprising: a processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the storage medium communicate through the bus, and the processor executes the machine-readable instructions to perform the steps of the pallet handling method.

[0031] A fourth aspect of the present application provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the pallet handling method when the computer program is executed by a processor.

[0032] Beneficial effect: When responding to the stacking instruction, the present application determines the stacking height or number of layers according to the current height or number of layers of the target stacking position. Since the task generated first often has a higher probability of arriving first, the present application determines the stacking height or number of layers when responding to the stacking instruction. Under normal circumstances, the task generated first arrives first. Each transport cart can quickly complete the pallet placement action when it reaches the stacking position and drive away from the stacking position without waiting for the upper system to issue the stacking height or number of layers, nor does it have to upload the actual stacking position occupancy height and number of layers detected after arrival to the upper system, and then further wait for the upper system to analyze the stacking height or number of layers, and then further issue the stacking height or number of layers command to the cart, which makes scheduling complicated or the stacking efficiency is low.

[0033] In this application, when multiple transport carts are simultaneously executing pallet stacking tasks towards the same target stacking position, if a transport cart that responds to a later pallet stacking instruction arrives at the target stacking position first, the pallet stacking height or number of layers that should have been reached by the current transport cart is exchanged with the first-arrived transport cart. This allows the first-arrived transport cart to place its empty pallet and leave first, preventing the first-arrived cart from being unable to place its empty pallet and having to wait with it. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to describe the implementation of the above and other features of the present invention, a more particular description of the invention briefly described above will be presented with reference to exemplary embodiments of the invention shown in the accompanying drawings. It will be understood that these drawings depict only exemplary embodiments of the invention and are not to be considered limiting of its scope, and the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. In the drawings:

[0035] Figure 1 This is a pallet stacking flow chart provided by this application;

[0036] Figure 2 This is a flow chart of the order of stacking pallets at the same target stacking position provided by this application;

[0037] Figure 3 This is a flow chart of a method for updating the order of stacked pallets provided by the present application;

[0038] Figure 4 This is a flow chart of the order exchange of stacked trays at the same target stacking position provided by the present application;

[0039] Figure 5 This is another flow chart of the stacking order of pallets at the same target stacking position provided by this application; DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of this application.

[0041] In the first aspect of the present application, a method for stacking pallets using a transport robot is disclosed. Figure 1As shown, when an empty pallet is generated, a stacking instruction is generated accordingly. The stacking instruction includes the location information of the empty pallet and the number of empty pallets. Alternatively, a stacking instruction can be generated for each empty pallet. Such a stacking instruction includes the location information of the pallet but does not necessarily include the number of pallets, or the number of pallets is always 1. In response to the stacking instruction, a transport cart is dispatched to transport the empty pallet. After the stacking instruction is generated, an idle cart is selected to transport the empty pallet. The system first checks whether there are idle carts. If there are no idle carts, the stacking instruction is not executed. In this way, stacking can be performed between transport carts carrying goods, making the transport carts fully utilized without affecting the normal handling tasks. It also eliminates the need for dedicated personnel or vehicles to handle the scattered empty pallets, saving manpower and vehicles. When there is only one idle cart, the idle cart performs the stacking task. When there are multiple idle carts, the idle cart with the closest driving distance to the location of the empty pallet to be stacked is selected as the target transport cart to transport the empty pallet. It is necessary to first compare the travel distances of all idle carts to the position of the empty pallet to be stacked, and select the idle cart with the shortest travel distance to perform the stacking task, or select the cart with the shortest travel time to the position of the empty pallet to be stacked to perform the stacking task. Generally, the cart with the shortest travel distance will also have the shortest travel time. When there are multiple idle carts, the target transport cart to perform the stacking task can also be determined by traversal comparison. Specifically, first select one of the idle carts as the first idle cart, and compare the travel distances of other idle carts to the empty pallet to be stacked. This comparison of the travel distances of other idle carts to the empty pallet to be stacked is done one by one, in a certain order, such as in the order of the vehicle serial numbers, or without any order. If after traversal comparison, there is no idle cart closer than the first idle cart, then the first idle cart will be used as the target transport cart to transport the empty pallet; if there is a travel distance If there is a second idle cart that is closer to the first idle cart, the first idle cart will be eliminated, and the remaining idle carts will be compared with the second idle cart. If there is no idle cart closer than the second idle cart after the traversal and comparison, the second idle cart will be used as the target transport cart to transport the empty pallet. If there is a third idle cart that is closer than the second idle cart, the second idle cart will be eliminated, and the remaining idle carts will be compared with the third idle cart one by one until there is no idle cart that is closer to the empty pallet to be stacked than the Nth idle cart. In this case, the Nth idle cart will be selected as the target transport cart to transport the empty pallet. Selecting the nearest idle cart can improve the efficiency of pallet stacking. When there are multiple stacking instructions, each stacking instruction selects the idle cart with the closest travel distance to the empty pallet to be stacked to perform the task. This greatly improves the efficiency of stacking and helps the cart quickly complete the stacking task and quickly receive the transport task, thereby improving the operating efficiency of the entire warehouse.

[0042] Select the target stacking position. When there is only one stacking position, this stacking position will always be the target stacking position. When there are multiple stacking positions, you need to make a selection and select one from the multiple stacking positions as the target stacking position for this stacking instruction to execute the stacking task.

[0043] In one embodiment, the stacking position with the smallest pallet height or number of layers is selected as the target stacking position. This helps balance the tasks of each stacking position and avoids the situation where multiple transport vehicles are performing stacking tasks with the same stacking position as the target stacking position. When multiple vehicles arrive at the target stacking position, they need to wait for the previous vehicle to complete the stacking before the next vehicle can start the stacking task, resulting in a situation where many vehicles are stuck waiting. Specifically, the stacking position with the smallest height or number of layers of pallets actually placed on the stacking position can be selected, or the stacking position with the smallest stacking height or number of layers obtained by adding the height or number of layers in the stacking instruction with the stacking position as the target stacking position can be selected.

[0044] In another embodiment, the stacking position with the largest pallet height or number of layers is selected as the target stacking position. This helps to quickly release the stacking positions. The target stacking position is selected based on the principle of filling one stacking position first. In this way, the number of stacking positions that can be used to place empty pallets can be kept at the maximum release in real time, making it less likely that multiple pallets are stacked at the same time, leaving only a few or no stacking positions for empty pallets. This is because each time a stacking position is filled, the stacked empty pallets can be quickly moved away from the stacking position, thus freeing up the stacking positions. If the stacking positions are allocated evenly, it is likely that multiple stacking positions will be filled at the same time, leaving no or very few available stacking positions. Specifically, the stacking position with the largest height or number of pallets actually placed on the stacking position can be selected, or the stacking position with the largest height or number of layers obtained by adding the height or number of layers in the stacking instruction with the stacking position as the target stacking position can be selected.

[0045] The stacking height or number of layers is determined based on the current height or number of layers of the target stacking position. Specifically, when the target stacking position has no stacking instruction bound to it before the stacking instruction, that is, the stacking task is the first task of the stacking position, the current height or number of layers of the target stacking position is zero, and the stacking height or number of layers determined is based on zero height and zero layers. After the target stacking position is selected, that is, the stacking instruction has been bound to the target stacking position, the height or number of layers of the to-be-stacked pallets in the stacking instruction is added to the target stacking position, and the current stacking height or number of layers of the target stacking position is updated in preparation for the next stacking instruction. When the target stacking position is before the stacking instruction, there is already a stacking instruction bound to the stacking position. For ease of understanding, the bound stacking instruction is defined as the first instruction, and the stacking instruction to be bound is defined as the second instruction. At this time, the current height or number of layers of the target stacking position is the height or number of layers of the pallet to be stacked in the first instruction added to the height or number of layers of the target stacking position. Although sometimes when the second instruction is bound, the empty pallet of the first instruction has not yet been delivered to the stacking position, or the stacking has not yet been completed, the current height or number of layers of the target stacking position is still the height or number of layers of the pallet to be stacked in the first instruction added to the height or number of layers of the target stacking position. For example, if four empty pallets need to be stacked at stacking position A, the first instruction is: pallet 1 is stacked on the first layer above layer zero; the second instruction is: pallet 2 is stacked on the second layer; the third instruction is: pallet 3 is stacked on the third layer. A fourth instruction is then executed to obtain the current height or number of layers of the target stacking position. Even though it is possible that the empty pallets specified in the second and third instructions have not yet reached the target stacking position, that is, at this time, the only empty pallet currently occupied at the target stacking position is the empty pallet specified in the first instruction. In this case, the current height or number of layers of the target stacking position is still the height or number of layers after the third instruction is added. In other words, the fourth instruction is required to be placed on the fourth layer above the third layer. This facilitates management and real-time access to the stacking height of the stacking position. This prevents situations where multiple transport vehicles, bound to multiple stacking instructions, use the same stacking position as their target. Because the height after each instruction is completed is unknown, multiple transport vehicles with multiple stacking instructions may arrive at the target stacking position and become full or reach the upper limit before all pallets are stacked, causing congestion or the need to reselect the target stacking position.

[0046] If there is only one stacking instruction, then there will be no congestion or any complex situation when the transport cart corresponding to this stacking instruction arrives at the target stacking position to stack the trays. When there are a small number of stacking instructions, and each stacking instruction can connect to different stacking positions, that is, each stacking position currently has only one transport cart with a stacking instruction arriving at the target stacking position to stack the trays, there will be no congestion or any complex situation. However, in actual applications, there will be many stacking instructions and a limited or small number of stacking positions, that is, there will be a situation where multiple transport carts will simultaneously perform stacking tasks to the same target stacking position.

[0047] like Figure 2 As shown, when multiple transport carts are simultaneously executing pallet stacking tasks towards the same target stacking location, if a transport cart that responds to a later pallet stacking instruction arrives at the target location first, the pallet stacking height or number of layers that should have been reached by the current transport cart is swapped with the first-arriving transport cart. This allows the first-arriving transport cart to place its empty pallet and move on first, preventing the first-arriving cart from being unable to place its empty pallet and having to wait with it.

[0048] Specifically, for ease of understanding, let's take an example to explain the above situation. For example: there are currently 4 empty pallets, and 4 instructions are generated. These 4 instructions need to be stacked on stack position A. The first instruction: empty pallet 1 is stacked on the first layer above layer zero; the second instruction: empty pallet 2 is stacked on the second layer; the third instruction: empty pallet 3 is stacked on the third layer; the fourth instruction: empty pallet 4 is stacked on the fourth layer; if the trolley carrying empty pallet 4 reaches stack position A first, the trolley carrying empty pallet 1, the trolley carrying empty pallet 2, and the trolley carrying empty pallet 3 have not reached stack position A. At this time, the trolley carrying empty pallet 4 belongs to the trolley that responds to the subsequent stacking instruction, and the trolley carrying empty pallet 1 belongs to the trolley that should arrive currently. Then the height or number of layers of the first layer above layer zero is returned to the trolley carrying empty pallet 4, that is to say, let the trolley carrying empty pallet 4 place empty pallet 4 on the first layer above layer zero. In one embodiment, the height or number of layers of the first layer placed above the zero layer is returned to the trolley carrying empty pallet 4, that is, the trolley carrying empty pallet 4 places the empty pallet 4 on the first layer above the zero layer, and then or at the same time, the original stacking height or number of layers of the empty pallet 4 is exchanged with the trolley carrying empty pallet 1, that is, the stacking height or number of layers of the empty pallet 1 after the exchange is stacked on the fourth layer. However, the specific stacking height or number of layers of the empty pallet 1 is based on the time sequence of reaching the target stacking position. If the empty pallet 4 is placed on the first layer, and the trolley carrying empty pallet 1 arrives at the target stacking position immediately afterwards, the trolley carrying empty pallet 1 at this time belongs to the trolley that responds to the subsequent stacking instruction, and the trolley carrying empty pallet 2 belongs to the trolley that should arrive currently, then the exchange will continue, and empty pallet 1 will be placed on the second layer, and empty pallet 2 will be placed on the fourth layer, and so on, to perform the stacking operation.

[0049] In one embodiment, the pallet stacking method further includes confirming the actual occupancy of the target stacking position after the transport trolley arrives at the target stacking position, and determining whether the actual occupancy of the stacking position matches the stacking height or number of layers of the transport trolley. If the transport trolley arrives at the target stacking position without first determining the actual occupancy, when the transport trolley places the pallet according to the stacking height or number of layers determined by the current height or number of layers of the target stacking position when the original stacking instruction is issued, the following two situations may occur. In the first situation, the transport trolley arrives relatively early, and the trolleys of the previous stacking instructions have not arrived yet. At this time, the height or number of pallets on the stacking position has not yet reached the height or number of layers that the transport trolley should be placed. The transport trolley places the pallet according to its predetermined stacking height or number of layers. When placing pallets in layers, the pallets will fall from a high place, and it is very easy to cause the pallets to be tilted or fall or the entire stack of empty pallets to collapse when they fall on the stacking position; in the second case, the transport cart arrives relatively late, and many transport carts that were originally arranged behind it in the stacking order have already completed stacking. At this time, the height or number of pallets on the stacking position is higher than the height or number of layers that the transport cart should be placed. When the transport cart places the pallets according to its predetermined stacking height or number of layers, it will push the originally stacked empty pallets away from the stacking position, causing the empty pallets to fall to the ground in a scattered manner.

[0050] Specifically, when a transport cart carries the pallets to be stacked to the target stacking position, it is necessary to first determine whether the actual occupancy of the stacking position matches the stacking height or number of layers of the transport cart. The actual occupancy of the target stacking position is detected by sensors or obtained by the upper system. Regarding sensor detection, the radar, camera and other sensors built into the vehicle can be used to detect the height or number of layers of stacked pallets on the target stacking position. The radar can detect the total height of the stacked pallets on the stacking position. When all the pallets are standard pallets of the same height, the number of layers of pallets on the stacking position can also be further determined based on the total height and the height of each pallet. If the stacking height is determined based on the height of the actual occupancy, there is no need to further confirm the number of layers. Ordinary cameras or depth cameras can determine the height or number of layers of the actual occupancy.

[0051] Regarding obtaining information from the upper system, each transport cart performing the stacking task transports the empty pallet to the stacking position and uploads a task completion signal to the upper system after stacking is completed. The upper system sends the actual occupancy status of the stacking position based on the task completion signal. For example, when transport cart No. 1, which needs to be placed on the first layer, arrives at the stacking position with an empty pallet, the signal obtained from the upper system is that the stacking position is not occupied. In this case, it is considered that the first layer is empty. Transport cart No. 1 places the empty pallet on the first layer and further uploads the task completion signal. The upper system receives the task completion signal from cart No. 1 and determines that the first layer of the stacking position is actually occupied. Then, the next transport cart to arrive at the stacking position should be transport cart No. 2, which needs to be placed on the second layer. However, before cart No. 2 reaches the stacking position, cart No. 3, which needs to be placed on the third layer, arrives at the stacking position before cart No. 2. At this time, cart No. 3 obtains information from the upper system that the actual occupancy status of the stacking position is that the first layer is occupied and the second layer is not occupied. Since the pallets are stacked one by one, only the second layer can be stacked on the stacking position. However, if before trolley No. 2 arrives, trolley No. N arrives before trolley No. 2, and the actual occupancy of the stacking position does not match the stacking height or number of layers of trolley No. N, and needs to continue to exchange.

[0052] In an actual warehousing environment, during the process of warehousing, storage, and picking, empty pallets are generally not generated at once. For example, when the goods on a pallet are picked, an empty pallet that needs to be stacked is generated, and a stacking instruction is generated. The order in which the stacking instructions are generated is the same as the order in which the empty pallets are generated. Generally, empty pallets are generated one by one, but sometimes more than two empty pallets appear at the same time. For example, at the same picking station, multiple pallets are picked at the same time and become empty pallets. In order not to take up space, these empty pallets may be stacked together and wait for a transport cart to move them away for stacking. In actual applications, for the convenience of scheduling, a stacking instruction can be generated for each empty pallet. Even if two empty pallets are already stacked together, two stacking instructions are generated respectively, and two carts are dispatched to perform the stacking task. Alternatively, a stacking instruction can be generated for several empty pallets that are already stacked together, and a transport cart is dispatched to move the stacked pallets to the stacking position at one time.

[0053] like Figure 3 As shown, in one embodiment, after the stacking height or number of layers of the trays that are currently due to arrive at the transport cart is exchanged with the transport cart that arrived earlier, the current height or number of layers of the stacking position is updated, and the stacking heights and layers of the remaining transport carts are updated in sequence. The stacking heights and layers of the remaining transport carts are updated in sequence based on the updated current height or number of layers of the stacking position.

[0054] Generally speaking, the stacking order is the same as the order in which tasks are generated. For example, when the first task is generated, if there is an idle cart, the idle cart will be immediately sent to pick up the empty pallet and quickly transport the empty pallet to the stacking position for stacking. Therefore, in principle, the probability that the task generated first will arrive at the stacking position first will also be relatively high. Therefore, the stacking order of this application is determined according to the order in which the stacking instructions are generated. The earlier stacking instructions are placed below the target stacking position. In other words, if they are sorted by numerical sequence, the empty pallets of the stacking instructions with smaller sequence numbers will be placed below the empty pallets of the stacking instructions with larger sequence numbers. The target stacking position is selected for each stacking instruction in turn to determine the stacking height or number of layers. The number and number of empty pallets taken each time are different, which is conducive to reducing the number of trips of the transport cart. In other words, when multiple pallets are generated at the same time in a certain place, an idle cart can be used to make a one-time trip to transport multiple empty pallets generated to the stacking position.

[0055] The following example illustrates how to update the stacking height and level of subsequent transport carts. The following table shows the stacking instructions and the original sequence. In actual operation, the order in which the carts arrive at the stacking positions may differ from the original sequence.

[0056] For example, the actual arrival order is: instruction 1 arrives first, and the actual occupancy situation on the stacking position matches the stacking height or number of layers of the transport trolley, completing the stacking action; instruction 2 should arrive at the stacking position next, but the trolley executing instruction 4 arrives first. At this time, the layer number of instruction 2 needs to be returned to instruction 4, that is, the layer number of instruction 4 is changed to the second layer. Instruction 4 includes 3 pallets. The actual situation of the updated stacking position is that the first layer is occupied by instruction 1, and the second to fourth layers are occupied by instruction 4. The next pallet needs to be placed on the fifth layer.

[0057] There are two solutions for sequentially updating the stacking height or number of layers of subsequent transport carts:

[0058] The first method is to insert the early-arriving instruction 4 between instructions 1 and 2, while the other instructions are still arranged in the order in which they were generated. The updated order and the number of layers to be placed are shown in the following table:

[0059] The second method is equivalent to swapping the order of instruction 4 that arrived early with instruction 2 that should arrive. The order of other instructions is still based on the order in which the original instructions were generated as their order of arrival. The updated order and the number of layers to be placed are shown in the following table:

[0060] like Figure 4-Figure 5 As shown, in one embodiment, each stacking instruction includes the same pallet height or number of layers. When multiple transport carts are simultaneously executing stacking tasks toward the same target stacking position, if the transport cart that responds to the subsequent stacking instruction arrives at the target stacking position first, the stacking height or number of layers of the transport cart that is currently due to arrive will be exchanged with the transport cart that arrived first, including exchanging the task order of the transport cart that is currently due to arrive with the transport cart that arrived first. Specifically, since the pallet height or number of layers in each instruction is the same, the height or number of layers added to the stacking position is the same each time the tray is stacked. When the transport cart that responds to the subsequent stacking instruction arrives at the stacking position first, it is only necessary to exchange the task order of the transport cart that is currently due to arrive with the transport cart that arrived first. The following example is introduced in which each stacking instruction includes only one layer of pallets. The same height or number of empty pallets are stacked each time, making stacking easier to schedule. The stacking height or number of empty pallets is proportional to the height or number of empty pallets stacked each time, making it easy to calculate. When swapping the stacking order, there's no need to calculate the height or number of empty pallets; simply swap the order and the height or number of empty pallets. The following example shows stacking only one pallet at a time. Alternatively, you can stack two pallets each time, generating a stacking instruction when two empty pallets are generated and dispatching an idle cart to retrieve the empty pallet.

[0061] The order in which the instructions are generated is shown in the following table:

[0062] The actual arrival order is that the transport trolley of instruction 1 arrives first and completes the stacking, and the transport trolley of instruction 4 arrives next. In fact, the transport trolley of instruction 2 should arrive now.

[0063] You can only swap the execution order of instruction 2 and instruction 4, as shown in the following table:

[0064] After instruction 4 completes stacking, if the transport trolley of instruction 2 reaches the stacking position before instruction 3, the task order of instruction 3 and instruction 2 needs to be exchanged.

[0065] Alternatively, the stacking height or number of layers that should currently arrive at the transport cart is exchanged with the transport cart that arrives first, and the remaining trays that have not arrived at the transport cart are still determined in the order in which the stacking instructions are generated. As shown in the following table:

[0066] This is equivalent to moving the disk stacking task of instruction 4 to be executed before the disk stacking task of instruction 2.

[0067] The stacking position is provided with a preset height or number of layers. When the stacking height or number of layers reaches the preset height or number of layers, the stacking position is set to a state that cannot be used as a target stacking position. When the actual occupied height or number of layers of the stacking position that cannot be used as a target stacking position reaches the preset height or number of layers, a transport trolley is dispatched to move the stacked pallet away from the stacking position, and the stacking position resumes to a state that can be used as a target stacking position. The height or number of layers of empty pallets stacked on a specific stacking position cannot be infinitely high or unlimited. Generally, the upper limit height or number of layers of the stacking position can be set according to the lifting height of the transport trolley or for the stability of the transferred empty pallet stack. The upper limit height or number of layers of the stacking position can also be set according to other factors such as the empty pallet storage space. When the current stacking height or number of layers reaches the preset height or number of layers, that is, the Nth stacking instruction selects the target stacking position, and the height or number of layers of the pallets to be stacked of the Nth stacking instruction is added to the target stacking position, the height or number of layers of the pallets on the target stacking position reaches the preset height or number of layers, then the stacking position can no longer receive any empty pallets, although it is possible that the transport trolleys bound to the stacking position have not all been delivered, that is, the actual occupancy of the stacking position may not have reached the preset height or number of layers, and the stacking position is still in a state that cannot be used as a target stacking position and cannot receive any empty pallets. When all the transport carts assigned to the stacking position have arrived, the actual occupied height or number of layers of the stacking position reaches the preset height or number of layers. A transport cart is dispatched to move the stacked pallets away from the stacking position, and the stacking position becomes available again as a target stacking position. The current height or number of layers is updated. Since the full stack has just been moved, the empty pallet height and number of layers on the stacking position are now zero.

[0068] The stacking position can be designated as any position in the storage warehouse. For the handling cart with QR code navigation, any QR code position can be selected as the stacking position. The pallet has four sides, and the handling cart can empty the pallet from four directions on the four sides of the pallet, or can also empty the pallet from two directions on the two opposite sides of the pallet. When emptying from two directions on the two opposite sides, it can ensure that the forkable directions of all pallets are the same. If emptying the pallet from four directions, the forkable directions of the pallets on the stacked empty pallet stack will appear in the vertical direction. For example, for the pallets placed on the two intersecting sides of the pallet, their forkable directions are intersecting and perpendicular or almost perpendicular. According to actual needs, it is also possible to only allow emptying the pallet from 1 direction on one side of the pallet. Only allowing emptying the pallet from 1 direction on one side of the pallet, there will be no situation where multiple handling carts arrive at the same stacking position and place pallets simultaneously. If the stacking position allows emptying the pallet from directions on multiple sides of the pallet, when multiple handling carts arrive at different side directions simultaneously, the empty pallets will be placed in the order of generation of the stacking instructions. The stacking position does not specifically have any equipment facilities, etc. It can be any empty area on the map, it can be a ground marked area, it can also be any area designated by the upper system in the system map, or it can be any QR code in the storage warehouse.

[0069] In the second aspect of the present application, an electronic device is also disclosed, including: a processor, a storage medium, and a bus. The storage medium stores machine-readable instructions executable by the processor. When the electronic device runs, the processor communicates with the storage medium through the bus, and the processor executes the machine-readable instructions to perform the steps of the pallet handling method.

[0070] In the third aspect of the present application, a computer-readable storage medium is also disclosed, on which a computer program is stored. When the computer program is executed by a processor, the steps of the pallet handling method are implemented.

[0071] In the present application, a first detection component and a second detection component are simultaneously arranged on the handling robot. The first detection component is arranged at the bottom of the chassis and can identify the ground pallet and can also identify the edge of the cross-shaped pallet, enabling the picking component to be adjusted and accurately inserted into the pallet jack; the second detection component can detect non-ground pallets. In the same device, it can both detect ground pallets and non-ground pallets, and can detect both cross-shaped pallets and channel-shaped pallets, improving the accuracy and compatibility of pallet detection.

[0072] Certainly, the present application can also have many other embodiments. Without departing from the spirit and essence of the present application, those skilled in the art can make various corresponding changes and deformations according to the present application, but these corresponding changes and deformations should all fall within the protection scope of the claims attached to the present application.

Claims

1. A pallet stacking method using a transport robot, for stacking empty pallets into pallet stacks, characterized in that: The method comprises: In response to the stacking instruction, dispatch a transport trolley to transport the empty pallet; select a target stacking position, determine the stacking height or number of layers according to the current height or number of layers of the target stacking position, and control the transport trolley to transport the empty pallet to be stacked to the target stacking position for stacking; At the same stacking position, if a transport vehicle that responds to the subsequent stacking instruction arrives at the target stacking position first, the stacking height or number of layers that should have arrived at the transport vehicle will be exchanged with the transport vehicle that arrived first. The selecting of the target stacking position includes: Selecting a stacking position with the smallest current pallet height or number of layers as a target stacking position for the stacking instruction; Alternatively, a stacking position with the largest current pallet height or number of layers is selected as the target stacking position for the stacking instruction.

2. The method for stacking pallets using a transport robot according to claim 1, wherein: The dispatching of a transport trolley to transport an empty pallet includes selecting an idle trolley to transport the empty pallet, Select the idle trolley with the closest driving distance to the location where the empty pallets are to be stacked as the target transport trolley to transport the empty pallets.

3. The method for stacking pallets using a transport robot according to claim 1, wherein: The dispatching of a transport trolley to transport an empty pallet includes selecting an idle trolley to transport the empty pallet, If there are multiple idle carts, one of them is selected as the first idle cart, and the travel distances of other idle carts to the empty pallet to be stacked are compared. If a second idle cart appears with a travel distance closer than that of the first idle cart, the travel distances of the remaining idle carts to the empty pallet to be stacked are compared with the travel distance of the second idle cart to the empty pallet to be stacked, until no idle cart appears with a travel distance closer than that of the Nth idle cart to the empty pallet to be stacked, then the Nth idle cart is selected as the target transport cart to transport the empty pallet.

4. The method for stacking pallets using a transport robot according to claim 1, wherein: The stacking instruction includes position information of the empty pallets and quantity information of the empty pallets.

5. The method for stacking pallets using a transport robot according to claim 1, wherein: The dispatching transport trolley to transport the empty pallet includes: Check whether there is an idle cart. If there is no idle cart, the stacking instruction will not be executed.

6. The method for stacking pallets using a transport robot according to claim 1, wherein: The current pallet height or number of layers includes the height or number of layers of the pallet already placed on the stacking position, or includes the stacking height or number of layers obtained by adding the height or number of layers in the stacking instruction with the stacking position as the target stacking position.

7. The method for stacking pallets using a transport robot according to claim 1, wherein: The pallet stacking method further includes: adding the height or number of layers of the pallets to be stacked in the stacking instruction to the target stacking position, and updating the current stacking height or number of layers of the target stacking position.

8. The method for stacking pallets using a transport robot according to claim 1, wherein: The method includes, after the transport trolley arrives at the target stacking position, determining whether the actual occupancy situation on the stacking position is consistent with the stacking height or number of layers of the transport trolley, and if so, executing the stacking action; if not, determining the transport trolley that should execute the stacking height or number of layers based on the actual occupancy situation of the target stacking position, and exchanging the stacking heights or numbers of layers of the two transport trolleys.

9. The method for stacking pallets using a transport robot according to claim 1, wherein: The selection of the target stacking position includes: obtaining the height or number of layers of the pallets to be stacked in the stacking instruction, and selecting the stacking position with the smallest or largest current pallet height or number of layers as the target stacking position for the stacking instruction. The target stacking position must satisfy the current height or number of layers plus the height or number of layers of the pallets to be stacked in the stacking instruction, which does not exceed the preset height or number of layers of the stacking position.

10. The method for stacking pallets using a transport robot according to claim 1, wherein: The method includes exchanging the stacking height or number of layers that should currently arrive at the transport cart with the transport cart that arrives first, updating the current height or number of layers of the stacking position, and updating the stacking height or number of layers of the remaining stacking positions that have not arrived at the transport cart according to the updated current height or number of layers of the stacking position.

11. The method for stacking pallets using a transport robot according to claim 10, wherein: include: The stacking height or number of layers of the transport cart that is currently due to arrive is exchanged with the transport cart that arrived first. The remaining transport carts that have not arrived are still in the order of the generation of the stacking instructions as the arrival order. The stacking height or number of layers of the transport carts are updated in sequence according to the updated current height or number of layers of the stacking position; or The stacking height or number of layers of the current transport trolley that is due to arrive is exchanged with the transport trolley that arrived earlier, and the arrival order of the transport trolley that arrived earlier is returned to the current transport trolley that is due to arrive, and the arrival order of other transport trolleys remains unchanged.

12. The method for stacking pallets using a transport robot according to claim 1, wherein: The stacking height or number of layers that should arrive at the transport trolley is exchanged with the transport trolley that arrives first, including: The transport cart that is currently due to arrive exchanges its task order with the transport cart that arrived earlier, and the order of the remaining transport carts that have not arrived remains unchanged; or The stacking height or number of layers that should currently arrive at the transport trolley is exchanged with the transport trolley that arrived first, and the remaining transport trolleys that have not arrived are still determined in the order in which the stacking instructions are generated.

13. The method for stacking pallets using a transport robot according to claim 1, wherein: The stacking position is provided with a preset height or number of layers. When the current stacking height or number of layers reaches the preset height or number of layers, the stacking position is set to a state that cannot be used as a target stacking position. When the actual occupied height or number of layers of the stacking position that cannot be used as a target stacking position reaches the preset height or number of layers, a transport trolley is dispatched to move the stacked pallet away from the stacking position, and the stacking position resumes the state of being usable as a target stacking position.

14. An electronic device, characterized in that: include: A processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the storage medium communicate via the bus, and the processor executes the machine-readable instructions to perform the steps of the method for stacking pallets by a handling robot as described in any one of claims 1-13.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for stacking pallets by a transport robot according to any one of claims 1 to 13 are implemented.

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