Intelligent stereoscopic warehouse system of production line and control method of intelligent stereoscopic warehouse system

Abstract

The invention relates to an intelligent three-dimensional warehouse system of a production line. The intelligent three-dimensional warehouse system comprises a programmable logic controller, an intelligent gateway, an MLS management system and a manipulator. The programmable logic controller is used for executing logic operation including verification of timeliness of the current Token, a warehouse-in and warehouse-out searching algorithm and motion trail planning, and sending out a control instruction containing XYZ coordinates; the intelligent gateway is in communication connection between the programmable logic controller and the MLS management system, and is used for receiving register data of the programmable logic controller, packaging the register data into JSON format data, reporting the JSON format data, analyzing the JSON format data issued by the MLS management system and writing the JSON format data into the programmable logic controller; automation and intelligentization of the material transportation and storage process of the production line are achieved, and the overall response speed and operation reliability of a workshop conveying system are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent warehousing and automated control technology, and in particular to an intelligent automated storage and retrieval system for a production line and its control method. Background Technology

[0002] In modern industrial production, automated storage and retrieval systems (AS / RS) are key storage devices connecting production lines and logistics links. With increasing production capacity, production lines place higher demands on material turnover speed and storage density. Traditional AS / RS systems typically use stacker cranes or simple conveyor belts for transporting and retrieving goods.

[0003] However, existing automated storage and handling technologies suffer from the following technical bottlenecks:

[0004] Traditional robotic arms or actuators can only perform simple point-to-point movements and lack real-time linkage with the upper-level inventory management system (MLS). This means that when stacking goods at high density, robotic arms often cannot obtain accurate storage location coordinates (XYZ coordinates) in a timely manner, which can easily cause deviations in the placement of goods and affect the utilization rate of storage space.

[0005] In actual loading, unloading, and handling processes, the storage and retrieval of multi-layer racks must follow strict physical logic (e.g., when entering the warehouse, goods must be stacked from bottom to top to ensure a stable center of gravity; when leaving the warehouse, goods must be retrieved from top to bottom to prevent collapse). Existing control systems often lack this logical calculation capability for physical storage characteristics, which can easily lead to robotic arms forcibly extracting goods from the bottom layer, causing the stack to collapse or equipment to collide.

[0006] The lack of an efficient protocol conversion mechanism between the underlying control devices (such as programmable logic controllers) and the upper-level management system leads to a failure to update inventory data in a timely manner after physical goods are received into the warehouse. This asynchronous flow of information and physical goods often results in robotic arms repeatedly grabbing or placing items in full locations, severely impacting the logistics efficiency of the production line.

[0007] Therefore, there is an urgent need for an intelligent automated warehouse system that can deeply integrate logical operations and physical execution, enabling robotic arms to accurately grasp, stably stack, and efficiently transfer goods through precise coordinate control and efficient command interaction. Summary of the Invention

[0008] The primary objective of this invention is to provide an intelligent automated storage and retrieval system for production lines that enables automated, precise storage and efficient transport of materials.

[0009] The second objective of this invention is to provide a control method that improves the efficiency of material flow and operational safety of the entire workshop conveyor system.

[0010] The first objective of this invention is achieved as follows:

[0011] An intelligent automated storage and retrieval system (AS / RS) for a production line, the intelligent AS / RS including a programmable logic controller (PLC), an intelligent gateway, an MLS management system, and a robotic arm;

[0012] The programmable logic controller is used to execute logical operations including verifying the validity of the current token, the database search algorithm for inbound and outbound operations, and motion trajectory planning, and to issue control commands containing XYZ coordinates.

[0013] The intelligent gateway is communicatively connected between the programmable logic controller and the MLS management system. It is used to receive register data from the programmable logic controller, encapsulate it into JSON format data for reporting, and parse the JSON format data sent by the MLS management system and write it into the programmable logic controller.

[0014] The MLS management system, as the host computer, is used to distribute tokens, receive and record product information to complete the binding of physical goods and data, manage inventory data, and issue inbound and outbound instructions.

[0015] The robotic arm is communicatively connected to the programmable logic controller (PLC) and is used to perform the grasping and placing of goods according to the XYZ coordinates in the control instructions output by the PLC.

[0016] By constructing a hardware architecture that includes a programmable logic controller (PLC), a smart gateway, an MLS management system, and a robotic arm, the problem of incompatible communication protocols between the underlying industrial control equipment and the upper-level information management system is effectively solved. The smart gateway performs protocol conversion and encapsulates and parses JSON-formatted data, breaking down the barriers between "information flow" and "physical flow." This ensures that the robotic arm can execute the grasping and placement of goods based on verified and accurate instructions, achieving automation and intelligence in the material transportation and storage process of the production line, and significantly improving the overall response speed and operational reliability of the workshop conveyor system.

[0017] The second objective of this invention is achieved as follows:

[0018] A control method includes an inbound control process and an outbound control process;

[0019] The warehousing control process includes the following steps:

[0020] In step S100, after receiving the palletizing completion signal, the programmable logic controller verifies the validity of the current token; if the token expires, it requests a new token from the MLS management system through the smart gateway and writes it into the programmable logic controller.

[0021] Step S200, perform offline binding: The programmable logic controller sends the product information (including product model and product quantity) of the products to be put into the warehouse to the smart gateway. The smart gateway encapsulates the product information into JSON format data and reports it to the MLS management system. After receiving the binding success signal returned by the MLS management system, the identity of the goods is established.

[0022] Step S300, Execute the inbound request: The programmable logic controller initiates an inbound request to the MLS management system through the smart gateway. After receiving the inbound permission signal returned by the MLS management system, the inbound procedure is triggered.

[0023] Step S400: Perform the warehousing action: The programmable logic controller (PLC) calculates the XYZ coordinates of the target storage location according to the warehousing search algorithm, and controls the robotic arm to grab the goods and place them in the target storage location; after step S400 is completed, the PLC sends an warehousing completion signal containing the target storage location information to the MLS management system through the smart gateway.

[0024] The outbound control process includes the following steps:

[0025] Step S500, responding to the outbound request: The smart gateway receives the material requisition information containing the target product model from the MLS management system and writes it into the programmable logic controller. After the programmable logic controller verifies the validity of the current token, if the token is invalid, it requests a new token from the MLS management system through the smart gateway and writes it into the programmable logic controller; if the token is valid, the outbound procedure is triggered.

[0026] Step S600: Execute the outbound action: The programmable logic controller locates the storage location that matches the target product model according to the outbound search algorithm, calculates and outputs the XYZ coordinates of the storage location, and controls the robotic arm to take the goods out of the storage location.

[0027] By establishing a three-tiered interaction mechanism of "Token verification - offline binding - inbound request," combined with token verification during outbound processing, it is ensured that every inbound or outbound action is carried out only after obtaining legal authorization and confirming the accuracy of the information. This rigorous logical process effectively prevents erroneous actions of robotic arms due to information delays or errors (such as placing goods in the wrong storage location or picking up the wrong product model), ensuring the accuracy of logistics transportation on the production line. At the same time, the standardized separation design of the inbound and outbound processes allows the automated warehouse system to flexibly cope with high-frequency production cycles, improving the efficiency of goods turnover.

[0028] The second objective of this invention can also be achieved by the following technical measures:

[0029] Further, in step S400, the database search algorithm specifically includes:

[0030] Step S401: Enter the database search loop and sequentially poll the N columns of the database in a preset order;

[0031] Step S402: Determine whether the column being polled meets the inbound conditions. The inbound conditions include: the column is not full and the model of the goods stored in the column matches the model of the product to be inbound, or the column is an empty column.

[0032] Step S403: If the current column meets the entry conditions, then in that column, the preset number of M layers are polled in turn from bottom to top.

[0033] Step S404: When an idle storage space is found during polling, the idle storage space is determined as the target storage space, its corresponding XYZ coordinates are output, and the loop completion flag is set.

[0034] The "bottom-up" inbound polling and stacking strategy aligns with physical mechanics principles and the safety requirements of automated storage systems. When robotic arms perform inbound handling, the algorithm prioritizes filling the bottom shelf space, preventing top-heavy or suspended stacking safety hazards. This physically stable path planning significantly enhances the structural stability of the automated storage and retrieval system, preventing goods from tipping over or slipping during storage and maximizing the effective utilization of the automated storage space.

[0035] Further, in step S600, the outbound search algorithm specifically includes:

[0036] Step S601: Enter the database search loop and sequentially poll the N columns of the database in a preset order;

[0037] Step S602: Determine whether the column being polled currently contains goods that match the target product model in the material request information;

[0038] Step S603: If there is a product in the current column that matches the target product model, then in that column, a preset number of M layers are polled in turn from top to bottom.

[0039] Step S604: When polling reaches a layer containing goods, confirm that the goods in that layer are the target product, output its corresponding XYZ coordinates, and control the robot arm to perform the picking action.

[0040] By employing a top-down outbound polling and retrieval strategy, the robot arm's retrieval path is optimized. When performing outbound transport tasks, the algorithm ensures that the robot arm prioritizes removing the topmost goods, conforming to the "last-in, first-out" or physical stacking dismantling logic, effectively preventing the risk of upper goods collapsing due to the removal of lower-level goods. This not only ensures the safety of outbound operations but also reduces redundant movement of the robot arm between complex storage locations, improving the efficiency of goods flow from the automated warehouse to the next production stage.

[0041] Furthermore, the process of verifying the timeliness of the current Token in step S100 is as follows: the programmable logic controller reads the current system time and compares it with the Token expiration timestamp stored in the register. If the current system time exceeds the Token expiration timestamp, the Token is determined to be invalid.

[0042] The specific process for obtaining a new token is as follows: the programmable logic controller (PLC) sends the current time and the PLC's device ID to the smart gateway; the smart gateway packages the collected time and device ID into JSON format data and reports it to the MLS management system; after verification, the MLS management system returns JSON format data containing the new token; the smart gateway parses the JSON format data and writes the new token into the designated register of the PLC.

[0043] A dual verification mechanism using both device ID and timestamps ensures the timeliness and uniqueness of control commands. This mechanism prevents robotic arms from executing expired, invalid, or illegal commands, and guarantees the security of communication between the programmable logic controller (PLC) and the host computer even in fluctuating industrial network environments. This is particularly important for maintaining high-speed automated storage and retrieval systems (AS / RS) on production lines, effectively preventing equipment downtime or logistical disruptions caused by communication failures.

[0044] Furthermore, after steps S400 and S600 are completed, each step further includes: the programmable logic controller sending a completion signal to the MLS management system through the smart gateway. The completion signal includes the shelf number and shelf number of the target storage location, as well as the product model and product quantity bound to the target storage location. The smart gateway encapsulates the completion signal into JSON format data and reports it.

[0045] By sending JSON-formatted data feedback signals containing the target shelf number, shelf number, and corresponding product model and quantity after the inbound or outbound process is completed, closed-loop management of inventory data is achieved. This mechanism ensures real-time synchronization between the "book inventory" in the MLS management system and the "physical inventory" in the automated warehouse, eliminating "information silos." The precise feedback mechanism allows production line managers to grasp the exact location and status of every item in real time, thereby significantly improving the accuracy of production scheduling and the transparency of warehouse management.

[0046] The beneficial effects of this invention are as follows:

[0047] This invention effectively solves the problem of communication protocol incompatibility between the underlying industrial control equipment and the upper-level information management system by constructing a hardware architecture that includes a programmable logic controller, an intelligent gateway, an MLS management system, and a robotic arm. By utilizing the intelligent gateway for protocol conversion and JSON-formatted data encapsulation and parsing, the barriers between "information flow" and "physical flow" are broken down, ensuring that the robotic arm can execute the grasping and placement of goods based on verified and accurate instructions, thus achieving automation and intelligence in the material transportation and storage process of the production line.

[0048] The control method disclosed in this invention establishes a three-level interaction mechanism of "Token verification - offline binding - inbound request," and combines this with the timeliness of verifying the current token in the outbound process. This ensures that every inbound or outbound action is carried out only after obtaining legal authorization and confirming that the information is correct. This rigorous logical process effectively prevents malfunctions of the robotic arm due to information delays or errors, and guarantees the accuracy of logistics transportation on the production line.

[0049] This invention employs a bottom-up polling and stacking strategy during warehousing, which conforms to the principles of physics and mechanics and the safety requirements of three-dimensional storage. The algorithm forces goods to prioritize filling the bottom space of the shelves, avoiding the safety hazard of a top-heavy structure, significantly enhancing the structural stability of the vertical warehouse stack, and preventing goods from tipping over during storage.

[0050] This invention employs a top-down polling and retrieval strategy during outbound operations, optimizing the robotic arm's retrieval path. This algorithm ensures that the robotic arm prioritizes removing the topmost goods, conforming to the physical stacking dismantling logic and effectively preventing the risk of top goods collapsing due to the removal of bottom-level goods, thus guaranteeing the safety of outbound operations.

[0051] This invention obtains a token through a dual verification mechanism of device ID and timestamp, and uses local timestamp comparison for real-time failure judgment, ensuring the timeliness and uniqueness of control commands. This prevents the robot from executing expired or illegal operation commands and ensures communication security in the case of fluctuating network environment in industrial sites.

[0052] This invention enables closed-loop management of inventory data. After an action is completed, a feedback signal containing detailed product information and precise location information (shelf number and shelf number) is sent, ensuring that the "book inventory" in the MLS management system and the "physical inventory" in the automated warehouse are synchronized in real time, thereby improving the transparency of production scheduling and warehouse management. Attached Figure Description

[0053] Figure 1 This is the inbound control flowchart of the intelligent automated warehouse system.

[0054] Figure 2 This is the outbound control flowchart of the intelligent automated warehouse system. Detailed Implementation

[0055] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0056] Combination Figures 1 to 2 As shown in the figure, this embodiment discloses an intelligent automated storage and retrieval system (AS / RS) applied to a production line. The intelligent AS / RS mainly consists of four parts: a programmable logic controller (PLC), an intelligent gateway, an MLS (Material Logistics System) management system, and a robotic arm. Each part is connected to the other via an industrial bus or Ethernet.

[0057] Programmable Logic Controller (PLC): As the core logic control unit, it performs logical operations including token validity verification, database search algorithm calculation, and motion trajectory planning, and issues control commands. In this embodiment, the PLC is responsible for processing various sensor signals (such as conveyor platform arrival signals) and controlling the robot to perform precise physical movements based on the calculated XYZ coordinates (the physical coordinates of the cargo location in three-dimensional space).

[0058] Intelligent Gateway: Acting as a communication bridge, it connects the programmable logic controller (PLC) and the MLS management system. One end connects to the PLC via an industrial bus, reading and writing the PLC's registers; the other end connects to the MLS management system via a TCP / IP network. Its core function is to perform communication protocol conversion, encapsulating the PLC's register values ​​into JSON (JavaScript Object Notation) format data for reporting, and parsing the JSON data sent by the MLS and writing it into the PLC's registers.

[0059] The MLS management system, acting as the host computer, is used for token distribution, product binding verification, inventory data management, and issuing inbound and outbound instructions. "Product binding" refers to the MLS management system generating a unique inbound record ID in the database and associating it with the physical item information currently awaiting inbound, marking its status as "awaiting inbound." It is responsible for business logic verification and macro-level management of production scheduling.

[0060] Robotic arm: As a physical actuator, it is communicatively connected to the programmable logic controller (PLC). The robotic arm receives control commands (including XYZ coordinates) sent by the PLC and performs physical grasping, placement, and handling actions of goods between the conveyor and the automated storage and retrieval system.

[0061] Please refer to the inbound control process of the intelligent automated warehouse system. Figure 1 The warehousing control method in this embodiment mainly includes a data interaction stage and an action execution stage.

[0062] Data Interaction and Identity Verification (Steps S100-S300): After the goods on the production line conveyor are stacked, the programmable logic controller (PLC) receives the stacking completion signal and first triggers step S100 to verify the validity of the current token. Specifically, the PLC reads the current system time and compares it with the token expiration timestamp stored in the register. If the current time is later than the expiration timestamp, the token is deemed invalid. If invalid, the PLC sends the current time and device ID (device identifier) ​​to the smart gateway. The smart gateway packages this data into JSON format and reports it to the MLS. After successful verification by the MLS, it returns JSON format data containing the new token. The smart gateway parses this data and writes the new token into the designated register of the PLC.

[0063] Then, step S200 (offline binding) is executed: The programmable logic controller (PLC) submits the product information of the products to be put into storage (including product model and quantity, excluding storage location information at this stage) to the smart gateway. The gateway encapsulates this information into JSON format and reports it to the MLS interface. After completing the data binding in the background, the MLS management system returns a binding success signal, establishing the unique identity of this batch of goods. Next, step S300 (inbound request) is executed: The PLC initiates an inbound request, and after receiving the "inbound permission" signal from the MLS, the system enters the robotic arm motion control stage.

[0064] Action Execution and Warehouse Search Algorithm (Step S400): In step S400, the programmable logic controller calculates the target warehouse location according to a specific warehouse search algorithm. In this embodiment, the warehouse is set to contain 12 columns, and each column contains 3 layers.

[0065] The algorithm logic is as follows:

[0066] Step S401: The program enters the search loop, first polling N columns in a preset order (e.g., from column 1 to column 12). Step S402: Determine whether the currently polled column meets the inbound conditions, that is, determine whether the column is not full, and whether the model of the goods stored in the column matches the model of the product to be inbound, or whether the column is empty.

[0067] Step S403: If the current column meets the condition, then within that column, M layers are polled sequentially from bottom to top (i.e., Layer1->Layer2->Layer3).

[0068] Step S404: When an idle storage location is polled, the storage location is determined as the target storage location. The programmable logic controller calculates and outputs its corresponding XYZ coordinates and sets the loop completion flag.

[0069] The robotic arm uses these coordinates to grasp goods and place them in the target storage location. This bottom-up stacking strategy ensures that goods always fill the bottom space first, maintaining the stability of the automated storage and retrieval system's center of gravity and complying with physical storage safety regulations. After the operation is completed, the programmable logic controller (PLC) feeds back the actual target storage location information (including shelf number and shelf number) and XYZ coordinates to the MLS management system via a smart gateway. The MLS management system then updates the inventory data accordingly, completing the data loop.

[0070] Please refer to the outbound control process of the intelligent automated warehouse system. Figure 2 The outbound process in this embodiment is as follows:

[0071] In response to the outbound request (step S500), the MLS management system sends a "material request information" containing the target product model to the smart gateway based on production needs. The smart gateway receives this information and writes it into the register of the programmable logic controller. Before triggering the outbound procedure, the programmable logic controller also performs the verification of the validity of the current token as described in step S100 to ensure the legality of the instruction, and then triggers the outbound procedure.

[0072] Action Execution and Inventory Search Algorithm (Step S600): In step S600, the programmable logic controller executes the inventory search algorithm to locate the goods.

[0073] In step S601, the program enters the database search loop, first polling N columns in a preset order (e.g., columns 1-12).

[0074] Step S602: Determine whether the currently polled column contains a target product model that matches the material request information.

[0075] In step S603, if a matching column is found, M layers are sequentially polled in that column in the order from top to bottom (i.e., Layer3->Layer2->Layer1).

[0076] Step S604: When the layer containing the goods is polled, confirm that the goods are the target products, lock the coordinates and output them to the robot arm.

[0077] The robotic arm then performs the picking action, removing goods from the shelves and transporting them to the outbound area. Unlike the inbound logic, the outbound process uses a top-down polling sequence. This optimized physical logic ensures that the robotic arm always prioritizes picking up goods from the top layer, avoiding the risk of picking up goods from the bottom layer like "building blocks," effectively preventing the stack of goods from collapsing, and significantly improving the safety and stability of the workshop conveyor system. After the outbound process is completed, the programmable logic controller (PLC) sends a completion signal to the MLS via the smart gateway, completing the data loop.

[0078] The shelf number is used to represent the corresponding storage location number in MLS, N and M are preset positive integers, and the target product model is the product model specified in the material requisition information.

[0079] The database search algorithm includes an inbound database search algorithm and an outbound database search algorithm;

[0080] An automated storage system consists of N columns, each column has M layers, and the combination of each column and layer constitutes a storage location.

[0081] The shelf number is used to identify the column in the MLS management system, and the shelf number is used to identify the specific shelf within that column. Together, they uniquely identify a storage location.

[0082] The terms "first," "second," etc., used in this invention do not indicate any order, quantity, or importance, but are merely for distinction. The terms "a," "an," etc., used in this invention do not indicate a limitation on quantity, but rather indicate the existence of at least one of the mentioned objects. The terms indicating direction or location used in this invention, such as "top," "bottom," "side," "longitudinal," "transverse," "middle," "center," "outer," "inner," "horizontal," "vertical," "left," "right," "above," "below," etc., reflect relative positions, not absolute positions. The above-described embodiments merely illustrate several implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of this invention. Therefore, the protection scope of this invention should be determined by the appended claims.

Claims

1. An intelligent automated storage and retrieval system for a production line, characterized in that: The intelligent automated warehouse system includes a programmable logic controller, an intelligent gateway, an MLS management system, and a robotic arm; The programmable logic controller is used to execute logical operations including verifying the validity of the current token, the database search algorithm for inbound and outbound operations, and motion trajectory planning, and to issue control commands containing XYZ coordinates. The intelligent gateway is communicatively connected between the programmable logic controller and the MLS management system. It is used to receive register data from the programmable logic controller, encapsulate it into JSON format data for reporting, and parse the JSON format data sent by the MLS management system and write it into the programmable logic controller. The MLS management system, as the host computer, is used to distribute tokens, receive and record product information to complete the binding of physical goods and data, manage inventory data, and issue inbound and outbound instructions. The robotic arm is communicatively connected to the programmable logic controller (PLC) and is used to perform the grasping and placing of goods according to the XYZ coordinates in the control instructions output by the PLC.

2. A control method using the intelligent automated warehouse system as described in claim 1, characterized in that: This includes inbound control procedures and outbound control procedures; The warehousing control process includes the following steps: In step S100, after receiving the palletizing completion signal, the programmable logic controller verifies the validity of the current token; if the token expires, it requests a new token from the MLS management system through the smart gateway and writes it into the programmable logic controller. Step S200, perform offline binding: The programmable logic controller sends the product information of the products to be put into the warehouse to the smart gateway. The smart gateway encapsulates the product information into JSON format data and reports it to the MLS management system. After receiving the binding success signal returned by the MLS management system, the identity of the goods is established. The product information includes the product model and product quantity. Step S300, Execute the inbound request: The programmable logic controller initiates an inbound request to the MLS management system through the smart gateway. After receiving the inbound permission signal returned by the MLS management system, the inbound procedure is triggered. Step S400: Perform the warehousing action: The programmable logic controller (PLC) calculates the XYZ coordinates of the target storage location according to the warehousing search algorithm, and controls the robotic arm to grab the goods and place them in the target storage location; after step S400 is completed, the PLC sends an warehousing completion signal containing the target storage location information to the MLS management system through the smart gateway. The outbound control process includes the following steps: Step S500, responding to the outbound request: The smart gateway receives the material requisition information containing the target product model from the MLS management system and writes it into the programmable logic controller. After the programmable logic controller verifies the validity of the current token, if the token is invalid, it requests a new token from the MLS management system through the smart gateway and writes it into the programmable logic controller; if the token is valid, the outbound procedure is triggered. Step S600: Execute the outbound action: The programmable logic controller locates the storage location that matches the target product model according to the outbound search algorithm, calculates and outputs the XYZ coordinates of the storage location, and controls the robotic arm to take the goods out of the storage location.

3. The control method according to claim 2, characterized in that: In step S400, the database search algorithm specifically includes: Step S401: Enter the database search loop and sequentially poll the N columns of the database in a preset order; Step S402: Determine whether the column being polled meets the inbound conditions. The inbound conditions include: the column is not full and the model of the goods stored in the column matches the model of the product to be inbound, or the column is an empty column. Step S403: If the current column meets the entry conditions, then in that column, the preset number of M layers are polled in turn from bottom to top. Step S404: When an idle storage space is found during polling, the idle storage space is determined as the target storage space, its corresponding XYZ coordinates are output, and the loop completion flag is set.

4. The control method according to claim 2, characterized in that: In step S600, the outbound search algorithm specifically includes: Step S601: Enter the database search loop and sequentially poll the N columns of the database in a preset order; Step S602: Determine whether the column being polled currently contains goods that match the target product model in the material request information; Step S603: If there is a product in the current column that matches the target product model, then in that column, a preset number of M layers are polled in turn from top to bottom. Step S604: When polling reaches a layer containing goods, confirm that the goods in that layer are the target product, output its corresponding XYZ coordinates, and control the robot arm to perform the picking action.

5. The control method according to claim 2, characterized in that: The process of verifying the timeliness of the current Token in step S100 is as follows: the programmable logic controller reads the current system time and compares it with the Token expiration timestamp stored in the register. If the current system time exceeds the Token expiration timestamp, the Token is determined to be invalid. The specific process for obtaining the new token is as follows: the programmable logic controller (PLC) sends the current time and the PLC's device ID to the smart gateway; the smart gateway packages the collected time and device ID into JSON format data and reports it to the MLS management system; after verification, the MLS management system returns JSON format data containing the new token. The smart gateway parses the JSON format data and writes the new token into a designated register of the programmable logic controller.

6. The control method according to claim 2, characterized in that: After steps S400 and S600 are completed, each step further includes: the programmable logic controller sending a completion signal to the MLS management system through the smart gateway. The completion signal includes the product model, product quantity, shelf number and shelf number of the target storage location, and the smart gateway encapsulates the completion signal into JSON format data for reporting.

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