RGV in-and-out storage scheduling method, device and storage medium

Abstract

The present invention provides an RGV in-and-out scheduling method, device and storage medium. The RGV in-and-out scheduling method includes S1. a step of generating a target storage location set: generating a target storage location set for the RGV transport vehicle to enter the warehouse; the target storage location set has a plurality of optional storage locations, and the optional storage locations correspond to different lanes; S2. a step of judging whether to perform a storage entry operation: if there are available optional storage locations in the target storage location set, one of the available optional storage locations is selected to perform the storage entry operation; wherein available is defined as at least a buffer area that satisfies the corresponding lane has vacancies. The essence of the RGV in-and-out scheduling method is to reasonably determine the storage entry target of the RGV transport vehicle to optimize the operation plan of the RGV transport vehicle, which basically avoids the problem of the RGV transport vehicle stopping and waiting when exchanging materials with the stereoscopic warehouse, thereby ensuring the maximization of the operation efficiency of the RGV transport system.

Description

Technical Field

[0001] The present invention relates to the technical field of RGV task scheduling, and in particular to a RGV in-and-out storage scheduling method, device and storage medium. Background Art

[0002] Automated three-dimensional warehousing is promoted and applied in the manufacturing industry. The current production capacity of the photovoltaic module industry is still in the expansion stage. According to the report, from 2019 to 2023, China's annual production of photovoltaic modules has soared from about 100GW to about 500GW, with an average annual growth rate of 38%. Affected by the expansion of industry capacity, the application of automated logistics warehousing in the photovoltaic module industry has become a consensus.

[0003] The application of automated three-dimensional warehousing technology in the in-plant finished product inventory management of photovoltaic module products usually includes a three-dimensional warehouse with three-dimensional shelves and stackers as the core to expand the storage space, and a logistics system with AGV and RGV as the core to realize automated material transfer. Among them, in a logistics system with a fixed path, the task scheduling of AGV and RGV has a greater impact on the operating efficiency of the system. Taking the RGV conveying system of the ring conveyor line as an example, there are several loading and unloading areas. In addition, the track also passes through multiple different lane entrances of the warehousing system to transfer the goods to the stacker in the corresponding lane according to the instructions and then store them in the required storage location. Since the loading (unloading) of multiple RGVs, RGV walking and cargo transfer processes are carried out simultaneously, their respective operating states not only affect their own future behavior planning, but also affect the future behavior planning of other RGVs. Simple process control of a single RGV cannot guarantee the improvement of the system's operating efficiency. Instead, it will cause the RGV to be blocked and wait on the track, resulting in a decrease in overall operating efficiency.

[0004] AGV: automated guided vehicle.

[0005] RGV: railway guided vehicle, track guided vehicle. Summary of the invention

[0006] In order to reduce the occurrence of congestion and waiting in the RGV conveying system and improve the overall conveying efficiency of the RGV conveying system, the present application provides an RGV in-and-out scheduling method, device and storage medium.

[0007] The technical solution of the present invention provides a RGV in-and-out scheduling method, comprising:

[0008] S1, generating a target storage location set step: before the RGV transport vehicle enters the target storage location, generating a target storage location set for the RGV transport vehicle to enter the storage; the target storage location set has a plurality of optional storage locations, and the optional storage locations correspond to different lanes;

[0009] S2. Determine whether to perform the warehousing operation: If there are available optional warehouse locations in the target warehouse location set, select one of the available optional warehouse locations to perform the warehousing operation; available is defined as at least satisfying that there is a vacant space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the warehousing operation immediately after arriving.

[0010] Preferably, the optional storage locations in the target storage location set in the step of generating the target storage location set in S1 include at least one main storage location and at least one backup storage location; wherein the priority of the main storage location is higher than that of the backup storage location, and the backup storage location satisfies that at least one backup storage location is located downstream of all the main storage locations;

[0011] High priority means that for any RGV transport vehicle warehousing task corresponding to the same lane, when there are both warehousing tasks at the main storage location and warehousing tasks at the backup storage location, the warehousing tasks at the main storage location will be prioritized;

[0012] Downstream is defined as the position passed by the RGV conveyor relative to the direction of travel of the RGV conveyor;

[0013] In the step of S2 determining whether to perform the storage operation, S3 is executed to determine whether to perform the storage operation in the main storage location;

[0014] Among them, S3 is a step of judging whether to enter the warehouse in the main warehouse: judging whether there is an available main warehouse, if so, selecting one of the available main warehouses to perform the warehouse entry operation; if there is no available main warehouse, executing S4 to judge whether to enter the warehouse in the backup warehouse;

[0015] Among them, S4 is a step of judging whether to enter the warehouse in the reserve storage location: judging whether there is an available reserve storage location, and if so, selecting one of the available reserve storage locations to perform the warehouse entry operation.

[0016] Preferably, the step S4 determines whether there is no available reserve storage location in the reserve storage location entry step, and then the step S5 is performed to force the entry;

[0017] Among them, S5 is a forced warehousing step: selecting an available lane from the set of remaining lanes other than the lanes corresponding to the optional storage location to perform the warehousing operation.

[0018] Preferably, S3 determines whether the main storage location is available in the main storage location entry step in ascending order: if the current main storage location is available, the current main storage location is designated for the entry operation; if it is not available, the next main storage location is used as the current main storage location, and the determination operation is repeated;

[0019] Among them, the ascending order is the direction in which the corresponding lanes are arranged in sequence along the traveling direction of the RGV transport vehicle.

[0020] Preferably, S4 determines whether, in the warehousing step at the reserve storage location, the available reserve storage location satisfies that there is vacant space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the warehousing operation immediately after arrival, and that there is no to-be-completed warehousing task for the main storage location that occurs after the warehousing task corresponding to the reserve storage location in the task sequence known to the system or a subset of the known task sequences.

[0021] Preferably, the subset of the known task sequence is a task sequence that is to be completed within a preset time in the future starting from the current moment, wherein the preset time is positively correlated with the cycle time of the stacker.

[0022] Preferably, the step S4 determines whether the current reserve storage location is available in the reserve storage location entry step in ascending order: if the current reserve storage location is available, the current reserve storage location is designated for entry operation; if it is not available, the next reserve storage location is used as the current reserve storage location, and the determination operation is repeated;

[0023] Among them, the ascending order is the direction in which the corresponding lanes are arranged in sequence along the traveling direction of the RGV transport vehicle.

[0024] Preferably, S3 determines whether all available main storage locations are used as candidate storage sets in the main storage location storage step, and S6 selects a storage target storage from the candidate storage set to complete the storage operation;

[0025] or,

[0026] The step S4 determines whether all available reserve storage locations are used as candidate storage sets in the reserve storage location storage step, and the storage operation is completed by selecting a storage target from the candidate storage set in S6.

[0027] Preferably, in the step of selecting the storage target from the candidate storage set in S6, the upstream candidate is extracted from the candidate storage set in ascending order to perform the storage operation.

[0028] Preferably, in the step of selecting a storage target from the candidate storage set, S6 selects a candidate item that satisfies the shortest storage occupancy time at the candidate item to perform the storage operation;

[0029] Among them, for each candidate item in the candidate warehousing set, obtain the waiting task sequence on the stacker of the corresponding lane; estimate the duration of the stacker until the candidate item is warehousing based on the waiting task sequence, or estimate the duration of the stacker until the candidate item is warehousing based on the waiting task sequence after the warehousing task at the candidate item is attached; and use this duration as the occupancy time of the warehousing at the candidate item.

[0030] Preferably, in the step of selecting the warehousing target from the candidate warehousing set in S6, the set maximum value M of the remaining storage capacity is used as the threshold, and for the candidate items in the candidate warehousing set, all the candidate items with a storage capacity not less than M are selected as available candidates, and one candidate item is extracted from them to perform the warehousing operation.

[0031] Preferably, in the step of selecting a storage target from the candidate storage set for storage in S6: taking the set maximum value M of the remaining storage capacity as a threshold, for the candidate items in the candidate storage set, all the candidate items with storage capacity not less than M are selected as available candidate items; among the available candidate items, the candidate item corresponding to the one with the smallest trade-off standard S is selected as the storage target to perform the storage operation;

[0032] The trade-off standard S is defined as S=Aα+Tβ, where α is the storage capacity weight; β is the occupancy time weight;

[0033] A is the normalized remaining storage capacity, A=a / M, where a is the remaining storage capacity corresponding to the candidate;

[0034] T is the normalized occupancy time, T=t / H, where t is the occupancy time corresponding to the candidate item, and H is the occupancy time target preset by the system.

[0035] The present invention also provides a RGV in-and-out dispatching device, comprising:

[0036] a memory storing a computer program;

[0037] The processor is used to execute a computer program, and when the computer program is executed, the RGV in-and-out scheduling method described in any one of the above items is implemented.

[0038] The present invention also provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the processor executes the steps of any one of the above-mentioned RGV in-and-out scheduling methods.

[0039] The present invention provides an RGV in-and-out warehousing scheduling method for optimizing the operating efficiency of RGV transport vehicles. The essence of the method is to reasonably determine the warehousing target of the RGV transport vehicle to optimize the operating plan of the RGV transport vehicle, and dynamically allocate the warehousing target to the RGV transport vehicle during the operation of the RGV transport vehicle, thereby basically avoiding the problem of the RGV transport vehicle stopping and waiting when exchanging materials with the stereoscopic warehouse, thereby also avoiding the problem of track blockage caused by this, that is, avoiding the problem of multiple RGV transport vehicles stopping and waiting together, thereby ensuring the maximization of the operating efficiency of the RGV transport system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of a scenario in which the RGV in-and-out storage scheduling method of the present invention is applied;

[0041] Figure 2 It is a flow chart of the RGV in-and-out storage scheduling method of the present invention;

[0042] Figure 3 A flowchart of a more detailed embodiment of the RGV in-and-out storage scheduling method of the present invention;

[0043] Figure 4 It is a flowchart of another embodiment of the RGV in-and-out scheduling method of the present invention.

[0044] In the figure:

[0045] 1: three-dimensional warehouse; 11: aisle; 12: stacker; 13: buffer zone; 2: track; 3: RGV conveyor; 4: loading area; 41: loading position; 5: unloading area; 51: unloading position. DETAILED DESCRIPTION

[0046] The following is a detailed description of this patent type in conjunction with the accompanying drawings and specific embodiments. In this specification, the dimensions of the drawings do not represent the actual size ratios. The drawings are only used to reflect the relative position relationship and connection relationship between the components. Components with the same name or the same number represent similar or identical structures and are only for illustrative purposes.

[0047] The RGV in-and-out warehousing scheduling method of the present application can be applied to the warehousing system described below. Figure 1: is a schematic diagram of the storage system, which has a three-dimensional warehouse 1, which is provided with a plurality of lanes 11, and a mobile stacker 12 is arranged in the lanes 11, and a buffer zone 13 is arranged at the entrance of the lanes 11. During the outbound or inbound operation, the stacker 12 completes the transfer of materials between the buffer zone 13 and the corresponding storage positions on both sides of the lanes 11. The storage system includes a track 2 for a plurality of RGV transport vehicles 3 to travel, and the track 2 passes through the buffer zones 13 at the entrances of all lanes of the three-dimensional warehouse 1 in sequence. Under the operation of the relevant equipment of the buffer zone 13, the materials can be transferred between the RGV transport vehicles 3 located near the buffer zone 13 and the buffer zone 13. In addition, a loading area 4 and a unloading area 5 are planned on the path of the track 2. Generally, a plurality of loading positions 41 are arranged in the loading area 4, and a plurality of unloading positions 51 are arranged in the unloading area 5. The number of loading positions 41 and unloading positions 51 is determined by the planned production load. Similarly, the number of RGV transport vehicles 3 on the track 2 is also adjusted according to the production load. Track 2 is preferably a ring as shown in the figure, so as to realize the cyclic operation of the RGV transport vehicle. In fact, when it is a ring track, the system is generally provided with a sub-track that is controlled and connected to track 2. The sub-track is independent of the ring track and is connected to the temporary storage area for the RGV transport vehicle 3 to rest and maintain. The number of RGV transport vehicles 3 on track 2 can be dynamically adjusted through the sub-track to achieve matching with the production load.

[0048] The RGV transport vehicle 3 obtains the material from the loading area 4, stops at the designated buffer 13 to unload according to the received instructions, and then the stacker takes the material out of the buffer 13 and stores it in the designated storage location. For outbound delivery, the stacker takes the material out of the designated storage location and temporarily stores it in the buffer 13. The RGV transport vehicle 3 that is idle is assigned to load the material to the unloading area 5 for unloading. The number of turnover positions in the buffer is determined, but the number of turnover positions designed generally depends on the ratio of the planned outbound frequency to the inbound frequency. We can understand that when the number of turnover positions in the buffer 13 is large and all the inbound materials are temporarily stored, the outbound efficiency of the corresponding lane will be greatly affected, and vice versa. In this storage system, the number of turnover positions in a single buffer 13 is 2, which is a balance made according to the actual situation. It is obviously understandable that the RGV transport vehicle 3 on the track 2 can only move sequentially and cannot overtake and move. In fact, in order to avoid collisions, there may be mutual communication between RGVs, or there may be distance sensing to maintain the minimum safe distance between adjacent RGV transport vehicles 3. In this case, the blockage of a certain RGV transport vehicle 3 may affect the operating efficiency of several subsequent RGV transport vehicles 3. Therefore, the operating efficiency of a single RGV transport vehicle 3 may affect the operating efficiency of the system at an exponential level. A clear task goal is to reduce the possibility of blockage of the RGV transport vehicle 3 at any position on the track 2 as much as possible. Even if blockage occurs, its duration needs to be compressed. The blockage of the RGV transport vehicle 3 generally occurs in the buffer zone 13, the loading position 41 and the unloading position 51. Since the stacker 12 has a long operating time, avoiding blockage in the buffer zone 13 is the focus of human task scheduling. As for the situation at the loading position 41 and the unloading position 51, since they are related to the outside of the system, they have almost no impact on the operation within the storage system.

[0049] In the further optimization scheme of the above-mentioned warehousing system, in order to make full use of the space, the three-dimensional warehouse 1 may extend several floors in the height direction, and the three-dimensional warehouse 1 may be provided with more than one entry and exit area. It may be provided with a track 2 on the second floor to realize the material interaction with the internal production line, mainly the warehousing of finished products. On this basis, it may be provided with a platform outbound storage location on the bottom floor, which is used to ship goods from the three-dimensional warehouse 1 to the shipping operation area. Obviously, it is neither necessary nor possible to set up multiple stackers in the same lane to adapt to different entry and exit operation areas. Therefore, the stacker 12 in the same lane 11 needs to take into account the entry and exit requirements in the track 2 and the operation requirements of other entry and exit areas, which further increases the complexity of the system task scheduling.

[0050] Finally, the above-mentioned storage system is generally used for material storage, such as the storage of finished photovoltaic modules. In fact, these materials usually need to be carried by corresponding pallets and other turnover tools. In the preferred scheme, in order to make full use of the storage capacity of the storage system and avoid setting up a separate storage space for turnover tools, the empty turnover tools will be stored in the storage system like normal materials. At this time, the dispatch of empty turnover tools is part of the system function, which is essentially no different from the dispatch of materials. In this application, downstream always refers to the position passed by the RGV conveyor vehicle relative to the direction of travel of the RGV conveyor vehicle. With regard to the work tasks of the RGV, warehousing generally refers to unloading from the RGV conveyor vehicle to the buffer zone, and dispatching generally refers to loading from the buffer zone to the RGV conveyor vehicle.

[0051] We define that the lanes corresponding to any number of storage locations are in ascending order if they are arranged in the direction of travel of the RGV transport vehicle; conversely, if they are arranged in the reverse order of the direction of travel of the RGV transport vehicle, they are in descending order.

[0052] In order to improve the efficiency of RGV in and out of the warehouse in a storage system similar to the above, the present invention provides the following task scheduling method. Figure 2 , which performs the following scheduling steps on a single RGV transport vehicle 3.

[0053] S1. Generate a set of target storage locations: Before the RGV transport vehicle enters the target storage location, generate a set of target storage locations for the RGV transport vehicle to enter the warehouse. The system can send the target storage location set to the RGV transport vehicle, or send the warehousing instruction to the RGV transport vehicle after the subsequent decision is completed. The minimum condition for warehousing is to generate a target storage location for the RGV transport vehicle to enter the warehouse. At this time, the target storage location is directly sent to the RGV transport vehicle so that it stops and completes the warehousing operation when it reaches the buffer zone at the entrance of the lane corresponding to the storage location. However, due to the problem that the operating rhythm between the stacker, buffer zone and RGV transport vehicle cannot be completely consistent, the lack of a backup plan in this process may cause the RGV transport vehicle to stop at the track near the buffer zone of the lane corresponding to the target storage location and wait for the buffer zone to vacate the space for warehousing. Once such a situation occurs, the track will be blocked, affecting the transportation efficiency of multiple RGV transport vehicles. To avoid such problems, when the system generates target storage locations, the target storage location set should have several optional storage locations. When some of the target storage locations are blocked by RGV transport vehicles due to buffer occupancy, stacker time consumption, etc., other optional storage locations can be switched to for warehousing operations. This also requires that the optional storage locations should correspond to different lanes. That is, no two optional storage locations share the same lane.

[0054] S2. Determine whether to perform the storage operation: If there are available optional storage locations in the target storage location set, select one of the available optional storage locations and perform the storage operation. The available optional storage locations must at least have a vacant space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the storage operation immediately after arriving.

[0055] In this process, Figure 3 As shown, first, the availability of the optional storage locations can be determined in ascending order: if the current optional storage location is available, the warehousing operation is performed with the current optional storage location as the warehousing location; if the current optional storage location is not available, the availability of the next optional storage location is determined sequentially.

[0056] Furthermore, if all optional storage locations are unavailable (i.e., there is no next optional storage location), a backup solution is provided to ensure that the RGV transport vehicle does not perform invalid transport, i.e., the S5 forced warehousing step.

[0057] S5. Mandatory warehousing step: that is, selecting an available lane from all lanes of the stereoscopic warehouse, and having the RGV transport vehicle enter the warehouse into the buffer zone of the lane. Similarly, an available lane means that at least there is a vacant space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the warehousing operation immediately after arriving. In fact, in this technical solution, since it is known that the lanes corresponding to all optional storage locations are no longer available, selecting an available lane from all lanes of the stereoscopic warehouse is to select an available lane from the set of remaining lanes other than the lanes corresponding to the optional storage locations.

[0058] In this case, an available lane is selected from all the lanes of the high-bay warehouse, that is, an available lane is selected from the set of remaining lanes other than the lanes corresponding to the optional storage locations. During the process of the RGV transport vehicle entering the buffer zone of the lane, the lanes in the set of remaining lanes can be determined in ascending order to determine whether they are available. If the current lane is available, the lane is entered into the current lane; if the current lane is not available, the next lane is determined to be available.

[0059] In this case, an available lane is selected from all the lanes of the stereoscopic warehouse, that is, an available lane is selected from the set of remaining lanes other than the lanes corresponding to the optional storage locations. The process of the RGV transport vehicle entering the buffer zone of the lane can also use the set of remaining lanes as a candidate entry set, and the step of selecting the entry target from the candidate entry set in S6 is used to complete the entry operation.

[0060] It should be noted here that for the S5 forced warehousing step, the basis for the warehousing operation is the lane rather than the storage location. This is because the remaining storage locations are not specified in advance and are therefore not unique, so the task completed by the scheduling system is only to determine the lane that needs to be warehousing. As for the selection of a specific storage location in the lane, it has no effect on the warehousing process of the RGV transport vehicle. Although the task of selecting a suitable storage location from the lane is part of the system operation, it is actually independent of the task scheduling of the RGV transport vehicle, and it does not affect the work of the RGV, so there is no need to include it in the above steps. In an actual warehousing system, this can be done by the upper-level material planning system selecting a storage location from the remaining storage capacity of the lane according to the storage balance principle as the warehousing location and assigning it to the RGV transport vehicle, and the RGV transport vehicle still performs the same steps of the warehousing operation accordingly, that is, the goods are stored in the buffer zone of the lane corresponding to the warehousing location.

[0061] In step S2, if there are available optional storage locations in the target storage location set, one of the available optional storage locations can be extracted from all available optional storage locations to perform the storage operation. The determination of the specific extraction principle does not affect the integrity of the scheme. Therefore, we can use all available optional storage locations as candidate storage sets, and use S6 to select the storage target storage from the candidate storage set to complete the storage operation.

[0062] In actual application scenarios, the storage requirements for materials (such as photovoltaic modules) are subject to the rules of the corresponding storage system, and usually have a preferred target storage location, that is, for a storage system, the materials entering the warehouse are always assigned to a certain storage location in priority so that it meets certain material storage rules. Therefore, the priority of the optional storage locations in the target storage location set is preferably different to correspond to the actual storage requirements. In this case, the target storage location set should include at least one main storage location and several backup storage locations. Among them, the priority of the main storage location is the highest, and the priority of the backup storage location is lower than that of the main storage location. The priority here has two levels of meaning. First, for the same RGV transport vehicle, the priority of the main storage location is higher than the backup storage location, which means that as long as the main storage location meets the storage conditions, it is always prioritized to ensure storage at the main storage location. Second, for different RGV transport vehicles, this means that if there is a main storage location of an RGV transport vehicle and a backup storage location of another RGV transport vehicle at the same time because they are in the same lane and need to occupy the same buffer zone when entering the warehouse, the priority of the main storage location entering the warehouse is higher than the priority of the backup storage location entering the warehouse. Finally, in the same level of storage locations, such as the main storage location or the backup storage location, if there is no influence from other factors, the priority is the same. In addition, the backup storage location literally means a backup option when the main storage location is unavailable, and the running direction of the RGV transport vehicle is determined to move forward in a specific direction. In order for the backup storage location to play a role, it should generally meet the condition of being located downstream of the main storage location. Priority design ensures the operating efficiency while also ensuring that the materials in the stereoscopic warehouse are stored according to the rules set in the upper system as much as possible.

[0063] In the actual process, in order to give priority to certain storage rules, the basic scheduling steps are slightly optimized. The steps are as follows: Figure 4 .

[0064] S1. Generate a target storage location set: Before the RGV transport vehicle enters the target storage location, generate a target storage location set for the RGV transport vehicle to enter. The optional storage locations in the target storage location set are divided into primary storage locations and backup storage locations according to priority. There are multiple primary storage locations and backup storage locations, and the specific meaning of multiple here refers to at least one.

[0065] The main storage location can be one or more. When there is only one main storage location, it is obvious that the backup storage locations should be set downstream of the main storage location, otherwise the backup storage locations set upstream of the main storage location will never be used and therefore have no meaning. It is also necessary to consider the case where there are multiple main storage locations. At this time, it should be ensured that at least one backup storage location is located downstream of all main storage locations. This can ensure that under the worst conditions, when the most downstream main storage location among all main storage locations is still unavailable, there is an available backup storage location to provide a candidate. In fact, in a more specific case, all backup storage locations are downstream of the most downstream main storage location.

[0066] S2. Determine whether to perform the warehousing operation: Since the target storage location set is divided into the main storage location and the backup storage location according to the priority, determine whether to perform the warehousing operation in the main storage location or the backup storage location according to the priority order. That is, first determine whether to perform the warehousing step in the main storage location. If the main storage location is not available, then determine whether to perform the warehousing step in the backup storage location. The availability of the main storage location and the backup storage location means that at least there is a vacant space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the warehousing operation immediately after arriving.

[0067] For S3, the step of judging whether to enter the warehouse at the main warehouse, it is possible to judge whether the main warehouse is available in ascending order: if the main warehouse is available, then specify the main warehouse for the warehouse entry operation; if it is not available, judge whether the next main warehouse in ascending order is available. The main warehouse is available only when the RGV transport vehicle can enter the warehouse immediately after arriving at the buffer zone of the lane corresponding to the main warehouse. This generally means that there is space for entering the warehouse in the buffer zone and there is no failure in the buffer zone. The key is that immediate entry can avoid waiting and congestion of the RGV transport vehicle. This process is also applicable to the case where there is only one main warehouse. In practical applications, in order to take into account the complexity of the system and the actual storage rules, in most cases only one main warehouse is provided, and one or more backup warehouses are provided downstream thereof.

[0068] For the step S3 of determining whether to enter the warehouse in the main warehouse, all available main warehouses may be taken as candidate warehouse sets, and the warehouse operation may be completed by the step S6 of selecting a warehouse entry target from the candidate warehouse set.

[0069] The step of determining whether to enter the warehouse at the backup warehouse location in S4 is different from that at the main warehouse location. When the main warehouse location and the backup warehouse location are set in advance in the target warehouse location set, it is actually assumed that the priority of the backup warehouse location is lower than that of the main warehouse location. It is preferred to consider this priority difference when selecting the backup warehouse location.

[0070] The available backup storage location must first satisfy the requirement that there is space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the warehousing operation immediately after arrival. Since this can avoid the RGV transport vehicle from stopping and waiting, it is the basis for judging availability. In addition, as mentioned above, for different RGV transport vehicles, the priority of the backup storage location is also lower than that of the main storage location. It is also necessary to consider whether the application of the backup storage location affects the selection of the main storage location in the warehousing tasks of other RGV transport vehicles. Therefore, the available backup storage location must also satisfy the requirement that there is no pending warehousing task that occurs after the warehousing task corresponding to the backup storage location in the task sequence known to the system, which is the warehousing task for the main storage location.

[0071] Specifically, for a known warehousing task sequence in the system, or for a subset of a known warehousing task sequence in the system that is completed within a preset time from the current moment, we regard it as a warehousing task sequence. Confirm whether there is a main storage location of a certain warehousing task in the above warehousing task sequence and the backup storage location being confirmed that corresponds to the same lane. If so, it means that the backup storage location interferes with the main storage location of a subsequent warehousing task. In this case, the warehousing demand of the main storage location is prioritized, that is, the backup storage location is considered unavailable. Otherwise, if there is no main storage location interfering with it, the backup storage location is considered available. The preset time can be determined according to the beat of the buffer and the stacker, and usually needs to cover the beat time of the buffer or the stacker. For example, if the average beat time of the stacker is 2 minutes, at least all warehousing task sequences covering the next 2 minutes should be selected. And it is satisfied that there is no warehousing task for the main storage location that needs to be completed after the warehousing task corresponding to the backup storage location in the task sequence known to the system.

[0072] The above steps of judging whether to enter the warehouse at the reserve warehouse are generally executed in the ascending order of the reserve warehouse, that is, first judge whether the current reserve warehouse is available, and then judge whether the next reserve warehouse is available. In this case, if there is no further requirement, its logic is consistent with the sequential selection logic of the optional warehouse and the main warehouse, that is, it has a blocking effect. Specifically, it is to first judge whether the current reserve warehouse is available. If it is available, enter the warehouse at the current warehouse, otherwise judge whether the next reserve warehouse is available. The effect is that, like the sequential selection of the optional warehouse and the main warehouse, once a warehouse that meets the conditions appears, the entry operation is immediately executed, and the subsequent judgment process is no longer continued, thereby improving the operation efficiency of the system.

[0073] In the preferred case, it is still non-blocking, that is, all reserve storage locations are judged, all available reserve storage locations are found, and then one reserve storage location is selected to perform the storage operation. We can use all available reserve storage locations as candidate storage sets, and use S6 to select the storage target storage from the candidate storage set to complete the storage operation.

[0074] In extreme cases, if all backup storage locations are unavailable, a backup solution is still provided to ensure that the RGV does not perform ineffective transportation, namely the aforementioned S5 forced warehousing step.

[0075] The above technical solution involves the step of S6 selecting the entry target from the candidate entry set in many places. It will be executed in many different situations, and the source of the candidate entry set is different in different situations. When it enters from step S2, the candidate entry set is all available optional storage locations. When it enters from step S5, the candidate entry set is all remaining lanes. When it enters from step S3, the candidate entry set is all available main storage locations. When it enters from S4, the candidate storage location set is all available backup storage locations. Although the source of the candidate entry set is different in different situations, it is obvious that in the same situation, all candidates in the candidate entry set have the same priority for the RGV transport vehicle, and there is no distinction between primary and secondary.

[0076] In this case, the candidate items at the most upstream can be selected in ascending order for storage. For example, in the corresponding case, it can be the most upstream available optional storage location, the most upstream available main storage location, the most upstream available backup storage location or the most upstream remaining lane. Its essence is equivalent to the blocking sequential selection process mentioned above. It should be noted that the reason for selecting the upstream candidate in both the blocking sequential selection method and the ascending order selection is to provide a working method that releases the RGV transport vehicle's transport capacity the earliest, that is, the RGV is always required to provide the possibility of early release when the conditions are met, so that the RGV transport vehicle can resume the empty state as soon as possible. This is not only conducive to extending the endurance of the RGV transport vehicle, but the most important reason is to maximize the empty travel of the RGV transport vehicle on the track, thereby increasing the possibility of transferring the empty RGV transport vehicle for outbound operations in the same cycle. This avoids the additional allocation of empty RGV transport vehicles under outbound operation tasks to a certain extent, that is, it reduces the need to assign empty RGV transport vehicles for outbound operations from the starting point or before the loading and unloading areas.

[0077] However, it should be noted that there is no primary or secondary distinction in the candidate entry set. This is only for the RGV transport vehicle side. As for the global situation, the candidates in the candidate entry set have different effects on the global operating efficiency. The reason is that for the candidate, whether it is a storage location or an aisle, it will eventually correspond to the stacker and buffer in the corresponding aisle. Under dynamic operation conditions, the operating status and operating time of the buffer and stacker need to be considered, which means that different candidates have different occupancy times when they are used as candidate targets for warehousing, which affects the operating efficiency of the system. Occupancy time is the time that the material stays in the buffer before being taken away by the stacker. Longer occupancy time is obviously not conducive to the system's in-and-out scheduling, and increases the possibility of RGV transport vehicle blockage.

[0078] In a specific stereoscopic warehouse, the impact of the buffer zone can be almost ignored, and the main impact lies in the cycle time of the stacker. If the buffer zone has two buffer stations, the cycle time of the buffer zone to transfer materials between the two stations is less than 30s. As for the stacker, affected by the length of the lane and the number of floors of the stereoscopic warehouse, under extreme conditions, it takes about 2-6 minutes for the stacker to run from the far end to the buffer zone. Obviously, it is necessary to focus on the problem of excessive occupancy time caused by the stacker. On the other hand, we know that in specific scenarios, the stacker is multi-tasking, and its tasks are not limited to the exchange of materials with the RGV conveyor vehicle in and out of the warehouse system through the buffer zone. For example, in the technical solution of the multi-story stereoscopic warehouse given earlier in this application, in addition to being responsible for exchanging materials with the RGV conveyor vehicle in and out of the warehouse system on the second floor, the stacker is also responsible for the shipment operation from the first floor to the platform. At this time, the stacker itself is multi-tasking, which will further affect the cycle time of the stacker, causing the occupancy time of the candidate target to be further extended.

[0079] Therefore, one of the principles in the step of selecting the warehousing target from the candidate warehousing set in S6 is to select the technical solution with the shortest occupancy time. In order to achieve this principle, the system needs to perform the following operations. For each candidate item, the system will obtain the waiting task sequence on the stacker of the corresponding lane, and append the warehousing operation of the buffer material of the candidate item to the end of the waiting task sequence. The system estimates the duration of the stacker to take out the material from the buffer of the candidate item based on the waiting task sequence or the waiting task sequence after the additional operation, which is the occupancy time when warehousing at the candidate item. The candidate item corresponding to the solution with the shortest occupancy time is selected as the warehousing target. For the calculation of this duration, it can generally be disassembled into each task of the stacker. According to the task content, the starting and ending points or the operating mode of the stacker are determined, thereby determining the estimated time of a task, and the duration of the entire waiting task sequence can be estimated accordingly.

[0080] S6 Another principle in the step of selecting the target storage from the candidate storage set is the balance of storage capacity. The remaining storage capacity is defined as the percentage of the remaining storage locations corresponding to a certain lane to the total storage locations corresponding to the lane. In practical applications, there is a set minimum value m for the remaining storage capacity to ensure that there is always storage space in the lane. Similarly, for the consideration of storage capacity balance and selectivity of outbound storage, the maximum value M of the remaining storage capacity is generally set, which means that the system presets the range of the remaining storage capacity of the corresponding lane to be between mM. Exceeding this range, it will be preferably filled. In the aforementioned stereoscopic warehouse, the range of the remaining storage capacity is generally set to 30%-70%. As far as storage is concerned, the set maximum value M of the remaining storage capacity is used as the threshold. For the candidates in the candidate storage set, all candidates with a storage capacity not less than M are selected as available candidates, and one candidate is extracted from them to perform the storage operation. The extraction method does not need to be specifically limited. In the preferred method, the principle of extraction can be to extract according to the size of the remaining storage capacity value, that is, to extract the one with the largest remaining storage capacity to perform the storage operation. In another preferred manner, the principle of extraction is to extract the candidate items at the most upstream among all available candidate items in ascending order of the candidate items for storage.

[0081] In the preferred technical solution, it is necessary to take into account the balance between the occupancy time and the remaining storage capacity. The selection range is limited to all available candidates whose corresponding lanes have a remaining storage capacity not less than M. For the available candidates, the remaining storage capacity is denoted as a, the normalized remaining storage capacity is denoted as A=a / M, and the storage capacity weight is α; the corresponding occupancy time is denoted as t, the preset occupancy time target is selected as H (such as the maximum cycle time of the stacker), the normalized occupancy time is denoted as T=t / H, and the occupancy time weight is β. So we can get the dimensionless trade-off standard S, that is, S=Aα+Tβ. Take the candidate corresponding to the smallest S as the warehousing target to perform the warehousing operation. Because when we balance the occupancy time and the remaining storage capacity, the focus is generally on the optimization of the occupancy time, usually in the above weights, β>α. In the above-mentioned application of the stereoscopic warehouse, β is taken as 0.7 and α is taken as 0.3.

[0082] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0083] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0084] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0085] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0086] The above content only describes the preferred implementation methods of this patent type and does not limit the scope of this patent type. Without departing from the design spirit of this patent type, various modifications and improvements made to the technical solutions of this patent type by ordinary technicians in this field should fall within the protection scope determined by the claims of this patent type.

Claims

1. A method for dispatching RGV in and out of warehouse, characterized in that: include: S1, generating a target storage location set step: before the RGV transport vehicle enters the target storage location, generating a target storage location set for the RGV transport vehicle to enter the storage; the target storage location set has a plurality of optional storage locations, and the optional storage locations correspond to different lanes; S2, judging whether to perform the warehousing operation step: if there are available optional warehouse locations in the target warehouse location set, one of the available optional warehouse locations is selected to perform the warehousing operation; wherein available is defined as at least a buffer area of ​​the corresponding lane having vacancies for the RGV transport vehicle to complete the warehousing operation immediately after arriving; In the step of generating a target storage location set in S1, the optional storage locations in the target storage location set include at least one main storage location and at least one backup storage location; wherein the priority of the main storage location is higher than that of the backup storage location, and the backup storage location satisfies that at least one backup storage location is located downstream of all the main storage locations; High priority means that for any RGV transport vehicle warehousing task corresponding to the same lane, when there are both warehousing tasks at the main storage location and warehousing tasks at the backup storage location, the warehousing tasks at the main storage location will be prioritized; Downstream is defined as the position passed by the RGV conveyor relative to the direction of travel of the RGV conveyor; In the step of S2 determining whether to perform the storage operation, S3 is executed to determine whether to perform the storage operation in the main storage location; Among them, S3 is a step of judging whether to enter the warehouse in the main warehouse: judging whether there is an available main warehouse, if so, selecting one of the available main warehouses to perform the warehouse entry operation; if there is no available main warehouse, executing S4 to judge whether to enter the warehouse in the backup warehouse; Among them, S4 is a step of judging whether to enter the warehouse in the reserve warehouse location: judging whether there is an available reserve warehouse location, and if so, selecting one of the available reserve warehouse locations to perform the warehouse entry operation; The S4 determines whether, in the step of warehousing at the backup storage location, the available backup storage location satisfies that there is vacant space in the buffer zone of the corresponding lane for the RGV transport vehicle to complete the warehousing operation immediately after arriving, and whether there is no warehousing task for the main storage location that needs to be completed after the warehousing task corresponding to the backup storage location in the task sequence known to the system or a subset of the known task sequence; The subset of the known task sequence is a task sequence that is completed within a preset time in the future starting from the current moment, wherein the preset time is positively correlated with the cycle time of the stacker.

2. The RGV in-and-out scheduling method according to claim 1, characterized in that: The step S4 determines whether there is no available reserve storage location in the reserve storage location entry step, and then executes the step S5 of forced entry; Among them, S5 is a forced warehousing step: selecting an available lane from the set of remaining lanes other than the lanes corresponding to the optional storage location to perform the warehousing operation.

3. The RGV in-and-out scheduling method according to claim 1, characterized in that: S3 determines whether the main storage location is available in the main storage location entry step in ascending order: if the current main storage location is available, the current main storage location is designated for entry; if it is not available, the next main storage location is used as the current main storage location, and the determination operation is repeated; Among them, the ascending order is the direction in which the corresponding lanes are arranged in sequence along the traveling direction of the RGV transport vehicle.

4. The RGV in-and-out scheduling method according to claim 1, characterized in that: The step S4 determines whether the current reserve storage location is available in the reserve storage location entry step in ascending order: if the current reserve storage location is available, the current reserve storage location is designated for entry operation; if it is not available, the next reserve storage location is used as the current reserve storage location, and the determination operation is repeated; Among them, the ascending order is the direction in which the corresponding lanes are arranged in sequence along the traveling direction of the RGV transport vehicle.

5. The RGV in-and-out scheduling method according to claim 1, characterized in that: S3 determines whether all available main storage locations are used as candidate storage sets in the main storage location storage step, and S6 selects a storage target storage from the candidate storage set to complete the storage operation; or, The step S4 determines whether all available reserve storage locations are used as candidate storage sets in the reserve storage location storage step, and the storage operation is completed by selecting a storage target from the candidate storage set in S6.

6. The RGV in-and-out scheduling method according to claim 5, characterized in that: In the step of selecting a storage target from the candidate storage set in S6, the upstream candidate is extracted from the candidate storage set in ascending order to perform the storage operation.

7. The RGV in-and-out scheduling method according to claim 5, characterized in that: The step S6 of selecting a storage target from the candidate storage set is to select a candidate item that satisfies the requirement of the shortest storage time at the candidate item to perform the storage operation; Among them, for each candidate item in the candidate warehousing set, obtain the waiting task sequence on the stacker of the corresponding lane; estimate the duration of the stacker until the candidate item is warehousing based on the waiting task sequence, or estimate the duration of the stacker until the candidate item is warehousing based on the waiting task sequence after the warehousing task at the candidate item is attached; and use this duration as the occupancy time of the warehousing at the candidate item.

8. The RGV in-and-out scheduling method according to claim 5, characterized in that: In the step of selecting the target entry from the candidate entry set in S6, the maximum value M of the remaining storage capacity is set as the threshold. For the candidate items in the candidate entry set, all the candidate items with storage capacity not less than M are selected as available candidate items, and one candidate item is extracted from them to perform the entry operation.

9. The RGV in-and-out scheduling method according to claim 5, characterized in that: In the step of selecting a storage target from the candidate storage set for storage in S6: taking the set maximum value M of the remaining storage capacity as a threshold, for the candidate items in the candidate storage set, all the candidate items whose storage capacity is not less than M are selected as available candidate items; among the available candidate items, the candidate item corresponding to the one with the smallest weighting standard S is selected as the storage target to perform the storage operation; The trade-off standard S is defined as S=Aα+Tβ, where α is the storage capacity weight; β is the occupancy time weight; A is the normalized remaining storage capacity, A=a / M, where a is the remaining storage capacity corresponding to the candidate; T is the normalized occupancy time, T=t / H, where t is the occupancy time corresponding to the candidate item, and H is the occupancy time target preset by the system.

10. An RGV in-and-out dispatching device, characterized in that: include a memory storing a computer program; A processor is used to execute a computer program, and when the computer program is executed, the RGV in-and-out warehousing scheduling method as described in any one of claims 1-9 is implemented.

11. A computer-readable storage medium, characterized in that: A computer program is stored, and when the computer program is executed by a processor, the processor is caused to execute the steps of the RGV in-and-out warehousing scheduling method as described in any one of claims 1-9.

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