Control system and method for intelligent distribution and intelligent sorting of materials

Abstract

The invention discloses a material intelligent distribution and intelligent sorting control system and method, and relates to the technical field of nonferrous metallurgy, and the system comprises an MES system, an RMS system, an AGV system, an ROB system and a PLC control system; the MES system is used as an information management layer; the RMS system is used as a central control management layer; and the PLC control system is used as a control management layer. According to the control system and method for intelligent distribution and intelligent sorting of the materials, the control mode, the PLC control program and the robot control program have no relation with the formula type, number and proportion and can be arbitrarily specified by an MES system, the control mode is flexible, and operation is easy. When the technology is changed, reprogramming and debugging are not needed, the MES system only needs to issue the changed formula requirement, the control system can complete intelligent distribution and feeding tasks, the rapid experiment research and development and online requirements of new products are met, the system adaptability is high, and the application scene is wide.

Description

Technical Field

[0001] The present invention relates to the technical field of nonferrous metallurgy, and in particular to a control system and method for intelligent distribution and intelligent sorting of materials. Background Art

[0002] At present, the degree of automation in the nonferrous metallurgical industry is low. The traditional method in the antimony ingot smelting workshop is generally to manually label the materials, and then manually carry out the handling, sorting and feeding work according to the raw material identification and the required raw material batch number.

[0003] For distribution and decomposition automation equipment in other industries, the required raw materials for the feeding station are generally selected manually according to the preset formula and ratio, and the equipment planning is designed. The incoming feeding station is designed as multiple incoming feeding stations (assuming X), and the required raw materials are transported to the corresponding fixed incoming feeding stations by pallet loading. The feeding port is also designed as multiple feeding stations (assuming Y). According to the formula and ratio of the raw materials required for the feeding station, the task queue process program required for automatic feeding is written into the PLC control system in advance. The robot engineer teaches the path trajectory of X picking stations and the path trajectory of Y feeding stations, and arranges and combines each picking action and feeding action to obtain C=X*Y combinations, and presets C different program numbers respectively. Then, the electrical engineer cyclically calls the preset program number of the robot according to the task queue and feeding time to control the industrial robot to complete the feeding work.

[0004] However, in the actual antimony ingot smelting workshop, since each pallet of antimony ingots weighs about 1 ton, the raw materials required for production are transported manually or by forklift, which is labor-intensive and inefficient. In addition, the smelting of antimony ingots has strict requirements on the feeding time and feeding ratio of raw materials. If manual feeding is used, the feeding needs to be done once every 1 minute, and repeated work is prone to errors and omissions, making it difficult to control the quality of the smelted products. In addition, the raw materials fed are recorded manually, which is prone to recording errors, inefficiency, and cannot be traced.

[0005] In addition, the temperature of the combustion furnace in the antimony ingot smelting workshop is generally around 1000 degrees, and the air temperature in the working area is also over 100 degrees Celsius, which is a bad environment. During the manual handling and feeding process, it is easy to get burned, the labor intensity is high, and the efficiency is low.

[0006] However, if programming is done through budget formulas and ratios, each corresponding model product needs to be programmed, which results in a lot of repetitive work and a complex program structure. In addition, the raw materials required for the incoming material station need to be preset and solidified in advance by the debugging personnel according to the formula and ratio relationship. After the process formula is changed, the relevant programs need to be rewritten and debugged, which is inflexible. The ES system can only call products with preset formulas and ratio programs. When adding or changing processes, professional technicians must redesign and debug the program. The system has poor flexibility and a long debugging cycle, which affects the rapid experimental development and launch of new products.

[0007] Therefore, it is urgent to improve this shortcoming. The present invention studies and improves the existing technology and its shortcomings, and provides a control system and method for intelligent distribution and intelligent sorting of materials. Summary of the invention

[0008] The purpose of the present invention is to provide a control system and method for intelligent material distribution and intelligent sorting to solve the problems raised in the above background technology.

[0009] To achieve the above object, the present invention provides the following technical solutions: On the one hand, it provides a control system for intelligent material distribution and intelligent sorting, including MES system (intelligent manufacturing management system), RMS system (production scheduling system), AGV system, ROB system (industrial robot system) and PLC control system (electrical control system); As the information management layer, the MES system plays a key role in the production process and is responsible for the execution of production plans, process recipe management, real-time monitoring, data collection and analysis, etc., thus improving production efficiency and quality; The RMS system, as the central control management layer, is a bridge connecting the MES system, AGV system, and PLC control system. It is used for seamless connection between the downstream control management layer (PLC) and the upstream information management layer (MES), as well as the collaborative work, intelligent centralized control, and unified management of multiple PLC control systems and AGV systems. The PLC control system serves as the control management layer, specifically using Siemens PLC as a processor for computing, control, storage and other functions. It communicates with the RMS system using Ethernet, and communicates with remote I / O sites, RFID readers, ROB systems, etc. using PROFINET fieldbus, which has higher processing and response speeds, a distributed structure, and is convenient for fault detection and maintenance.

[0010] Furthermore, the MES system issues tasks to the RMS system, and the tasks include the formula batch number, formula ratio, feeding time, feeding station, etc. of the antimony ingot raw materials.

[0011] Furthermore, the remote I / O site detects the device status by detecting sensors.

[0012] Furthermore, the RFID reader uses a Pepperl+Fuchs ultra-high frequency read / write module to write the information of the antimony ingot raw materials in the pallet (such as raw material batch, quantity, name, grade, chemical composition, etc.) into the RFID chip, ensuring the accuracy of the pallet data during the transportation process, reducing management errors, stabilizing and reliably, and making the production process more transparent, thereby improving production efficiency.

[0013] Furthermore, the ROB system scans the position coordinates of the antimony ingot raw materials to be grasped in the tray through a 3D vision camera to guide the industrial robot to complete a fully automatic and precise grasping action.

[0014] Furthermore, the industrial robot grasping fixture adopts a cylinder grasping method and is equipped with a photoelectric sensor to detect whether the antimony ingot raw material has fallen. The solenoid valve of the industrial robot adopts a three-position five-way structure. When the gripper suddenly loses power or gas, it will remain in the current state to ensure that the antimony ingot raw material will not fall, thereby ensuring the stability and safety of the system.

[0015] Furthermore, the material allocation principle of the incoming material station of the system is: the number of incoming material stations must be designed to be greater than the types of raw material batches in the formula, so that each raw material batch can be allocated at least one incoming material station, ensuring that each ratio material has a tray placed at the incoming material station, and then in order of the ratio value, the raw material batch with a large ratio value is allocated to a spare station first, so as to improve the material flow efficiency and reduce the probability of waiting for material shortages.

[0016] Furthermore, the system sets the incoming material station allocation subroutine according to the allocation principle by the PLC control system. In this way, the raw material batch number in the incoming material station does not need to be set manually. The raw material batch number issued by the MES system can be automatically allocated to the incoming material station through the preset program, and the spare station can be allocated according to the optimal material pulling efficiency.

[0017] Furthermore, when the PLC control system detects that the original material station is out of material, it will automatically call the AGV to transfer the required raw material batch number from the raw material warehouse to the original material station. This method does not require any human intervention in the entire process. The specific operations are as follows: the PLC control system decomposes the tasks according to the formula batch number and ratio relationship issued by the MES system, and automatically plans the raw material batch number required for the incoming material station, and calls the AGV for fully automatic material transfer, thereby realizing intelligent material distribution.

[0018] On the other hand, a control method for intelligent material distribution and intelligent sorting is provided, which is applied to a control system for intelligent material distribution and intelligent sorting as described above, and includes the following steps: S1. The MES system specifies and issues task requirements, including the formula and ratio of antimony ingot raw materials, feeding time, feeding station (combustion furnace feeding port), etc. S2, after receiving the task, the RMS system transfers it to the PLC control system of the designated control layer; S3, PLC control system decomposes tasks according to the formula batch number and ratio relationship, automatically calculates the feeding task queue, and automatically plans the raw material batch number required for the incoming material station; S4, the PLC control system calls the AGV system to transport the required batches of antimony ingot raw materials to the incoming material station; S5, the PLC control system queries the currently required raw materials for feeding according to the feeding task queue of the upper system, and confirms the placement location of the raw materials (incoming material station), that is, the robot picking station; S6, the PLC control system determines whether there is material on the tray in the target material-picking station, and if so, proceeds to step S8; if not, the PLC control system calls the AGV system to transport the required batch of antimony ingot raw materials to the incoming material station, and proceeds to step S7; S7, the PLC control system determines whether there is material on the pallet in the target standby material-retrieving station. If there is material, it proceeds to step S8; if there is no material, the PLC control system calls the AGV system to transport the required batch of antimony ingot raw materials to the incoming material station, and proceeds to step S6 for re-judgment; S8, the PLC control system sends the target material picking station and the target material feeding station to the industrial robot according to the current material feeding task; S9, the industrial robot moves to the top of the station tray according to the material picking station number specified by the PLC; S10, 3D vision scans the position coordinates of the antimony ingot raw materials in the tray and guides the robot to perform grabbing actions; S11. After the grabbing is completed, the PLC control system updates the data information of the raw materials in the pallet; S12, the industrial robot places the grabbed antimony ingot raw materials on the feeding platform according to the target feeding station specified by the PLC; S13, the pushing mechanism of the feeding platform pushes the antimony ingot raw materials into the combustion furnace for smelting; S14, when the current task is completed and the feeding time set by the upper system is reached, the next task is entered, and the cycle continues to step S5.

[0019] The present invention provides a control system and method for intelligent material distribution and intelligent sorting, which has the following beneficial effects: 1. The present invention has high compatibility and strong scalability. For the antimony ingot raw materials with different formulas required in the combustion furnace, the formula decomposition program of the PLC control system dispatches the robot to perform grabbing and feeding actions in turn as needed. The robot can complete all grabbing and handling actions under the guidance of vision without secondary programming, realizing intelligent unmanned feeding. Among them, 3D vision has no requirements for ambient light, strong applicability, and avoids tedious light source debugging.

[0020] 2. The present invention is that the manufacturing control system (MES) issues order tasks to the RMS system, and the RMS system issues formulas to the PLC control system according to the order requirements. The PLC control system calls the AGV to pull materials according to the production shortage requirements. There is no human involvement in the whole process, realizing a flexible, intelligent, digital, and unmanned production mode; materials can be fully automatically distributed and fed, reducing the impact of human factors, improving product quality, increasing job safety factors, and reducing labor intensity. The present invention is highly applicable, and similar material transportation and feeding schemes in other industries (such as food, chemical industry, etc.) can also be used as reference.

[0021] 3. The whole process of the present invention does not require manual participation. The PLC control system decomposes tasks according to the formula batch number and ratio relationship issued by the MES system, and automatically plans the raw material batch number required for the incoming material station, and calls AGV to automatically transport the materials, thus realizing the intelligent distribution of materials. In addition, the batch number type, quantity, and ratio in the formula can be arbitrarily set by the MES system according to the process requirements and then sent to the PLC control system. Without secondary programming, the industrial robot can complete the fully automatic material collection and feeding actions according to the set process requirements, thus realizing the intelligent feeding of materials.

[0022] In summary, the control method of the present invention, the PLC control program and the robot control program have nothing to do with the type, quantity, and ratio of the formula, and can be arbitrarily specified by the MES system. The control method is flexible and easy to operate. Moreover, when the process changes, this control method does not require reprogramming and debugging. The MES system only needs to issue the changed formula requirements, and the control system can complete the intelligent distribution and feeding tasks, meeting the rapid experimental development and launch requirements of new products. The system has strong adaptability and a wide range of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the control principle of a control system for intelligent material distribution and intelligent sorting of the present invention; Figure 2 This is an example diagram of raw material batch numbers and ratios of a control system for intelligent material distribution and intelligent sorting of the present invention; Figure 3 A schematic diagram of raw material batch number-raw material ratio of a control system for intelligent material distribution and intelligent sorting of the present invention; Figure 4This is a schematic diagram of the workstation number-raw material of a control system for intelligent material distribution and intelligent sorting of the present invention; Figure 5 The present invention is a flow chart of an intelligent control method for intelligent material distribution and intelligent sorting. DETAILED DESCRIPTION

[0024] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0025] like Figure 1-Figure 4 As shown, a control system for intelligent material distribution and intelligent sorting includes: MES system (intelligent manufacturing management system), RMS system (production scheduling system), AGV system, ROB system (industrial robot system) and PLC control system (electrical control system); As the information management layer, the MES system plays a key role in the production process. It is responsible for the execution of production plans, process recipe management, real-time monitoring, data collection and analysis, etc., which improves production efficiency and quality. In this embodiment, the MES system issues tasks to the RMS system, including the formula batch number, formula ratio, feeding time, feeding station, etc. of the raw materials of antimony ingots; As the central control management layer, the RMS system is a bridge connecting the MES system, AGV system, and PLC control system. It is used for seamless connection between the downstream control management layer (PLC) and the upstream information management layer (MES), as well as the collaborative work, intelligent centralized control, and unified management of multiple PLC control systems and AGV systems. The PLC control system is used as the control management layer. Specifically, Siemens PLC is used as the processor for calculation, control, storage and other functions. It communicates with the RMS system through Ethernet, and communicates with remote I / O stations, RFID readers, ROB systems, etc. through PROFINET fieldbus. It has higher processing speed and response speed, distributed structure, and convenient fault detection and maintenance. Remote I / O sites detect device status through detection sensors; The RFID reader uses a Pepperl+Fuchs UHF read / write module to write the information of the antimony ingot raw materials in the pallet (such as raw material batch, quantity, name, grade, chemical composition, etc.) into the RFID chip, ensuring the accuracy of the pallet data during the transportation process, reducing management errors, and ensuring a stable, reliable, and more transparent production process, thereby improving production efficiency. The ROB system uses a 3D vision camera to scan the position coordinates of the antimony ingot raw materials to be grabbed in the tray to guide the industrial robot to complete the fully automatic and precise grabbing action; the industrial robot grabbing fixture adopts a cylinder grabbing method and is equipped with a photoelectric sensor to detect whether the antimony ingot raw materials have fallen, and the solenoid valve of the industrial robot adopts a three-position five-way structure. When the gripper is suddenly powered off or the air is cut off, it will remain in the current state to ensure that the antimony ingot raw materials will not fall, ensuring the stability and safety of the system; The material allocation principle of the incoming material station of this system is: the number of incoming material stations must be designed to be greater than the types of raw material batches in the formula, so that each raw material batch can be allocated at least one incoming material station, ensuring that each ratio material has a tray placed at the incoming material station, and then according to the ratio value, the raw material batch with a large ratio value is allocated to a spare station first, so as to improve the flow efficiency of materials and reduce the probability of waiting for shortage of materials; According to the above principles, the PLC control system sets the incoming material station allocation subroutine. In this way, the raw material batch number in the incoming material station does not need to be set manually. The raw material batch number issued by the MES system can be automatically allocated to the incoming material station through the preset program, and the spare station can be allocated according to the optimal material pulling efficiency.

[0026] When the PLC control system detects that the original material station is out of material, it will automatically call the AGV to transfer the required raw material batch number from the raw material warehouse to the original material station. This method does not require any human intervention in the entire process. Specific operations: The PLC control system decomposes the tasks according to the formula batch number and ratio relationship issued by the MES system, and automatically plans the raw material batch number required for the incoming material station, and calls the AGV for fully automatic material transfer, realizing intelligent material distribution.

[0027] In this embodiment, the workstation allocation of different types of materials is as follows: 1) One material: one workstation is allocated for backup and one for use; 2) Two materials: Ratio: A:B=2:1, principle of workstation allocation: A (occupies 3 incoming material workstations), B (occupies 2 incoming material workstations); 3) Three kinds of materials: Ratio: A:B:C=1:2:3 First, ensure that each ratio of materials is placed in a station (A, B, C), and then place the remaining two stations with larger ratios: B and C; A (occupies 1 incoming material station), B (occupies 2 incoming material stations), C (occupies 2 incoming material stations); And so on... In this embodiment, the raw material feeding queue sequence analysis is as follows: Combination Figure 2As shown, the feeding queue Q=(A1, A2, ...Ai, B1, B2, ...Bj, C1, C2...Ck, ......, H1, H2, ...Hu) is derived. According to this feeding queue formula, the editing program sequentially queries the raw material batch numbers in the queue, and the raw material batch numbers required for the current feeding station can be obtained. After the specific location of the required raw material batch number at the incoming material station is queried through the preset program, the current target material picking station of the industrial robot can be obtained. The current feeding station can be arbitrarily specified by the MES system. In this way, the batch number type and ratio in the formula can be arbitrarily set by the MES system according to the process requirements and then sent to the PLC control system. Without secondary programming, the industrial robot can complete the fully automatic material picking and feeding actions according to the set process requirements, realizing the intelligent feeding of materials.

[0028] In the specific implementation process, it is assumed that the current antimony ingot production requires three raw material batches A, B, and C, and the ratio is 3:1:2. Figure 3 As shown; It can be deduced from this that the required material feeding queue for production is Q=(A, A, A, B, C, C); Workstation number and raw material batch number such as Figure 4 As shown, the ratio A=3>C=2>B=1, so stations 4 and 5 are allocated as spare stations for raw materials A\C.

[0029] like Figure 5 As shown, a control method for intelligent material distribution and intelligent sorting is applied to a control system for intelligent material distribution and intelligent sorting as described above, and includes the following steps: S1. When the whole line system is running automatically, the MES system specifies and issues task requirements, including the formula and proportion of antimony ingot raw materials, feeding time, feeding station (combustion furnace feeding port), etc. S2, after receiving the task, the RMS system transfers it to the PLC control system of the designated control layer; S3, PLC control system decomposes tasks according to the formula batch number and ratio relationship, automatically calculates the feeding task queue, and automatically plans the raw material batch number required for the incoming material station; S4, the PLC control system calls the AGV system to transport the required batches of antimony ingot raw materials to the incoming material station; S5, the PLC control system queries the currently required raw materials for feeding according to the feeding task queue of the upper system, and confirms the placement location of the raw materials (incoming material station), that is, the robot picking station; S6, the PLC control system determines whether there is material on the tray in the target material-picking station, and if so, proceeds to step S8; if not, the PLC control system calls the AGV system to transport the required batch of antimony ingot raw materials to the incoming material station, and proceeds to step S7; S7, the PLC control system determines whether there is material on the pallet in the target standby material-retrieving station. If there is material, it proceeds to step S8; if there is no material, the PLC control system calls the AGV system to transport the required batch of antimony ingot raw materials to the incoming material station, and proceeds to step S6 for re-judgment; S8, the PLC control system sends the target material picking station and the target material feeding station to the industrial robot according to the current material feeding task; S9, the industrial robot moves to the top of the station tray according to the material picking station number specified by the PLC; S10, 3D vision scans the position coordinates of the antimony ingot raw materials in the tray and guides the robot to perform grabbing actions; S11. After the grabbing is completed, the PLC control system updates the data information of the raw materials in the pallet; S12, the industrial robot places the grabbed antimony ingot raw materials on the feeding platform according to the target feeding station specified by the PLC; S13, the pushing mechanism of the feeding platform pushes the antimony ingot raw materials into the combustion furnace for smelting; S14, when the current task is completed and the feeding time set by the upper system is reached, the next task is entered, and the cycle continues to step S5.

[0030] The embodiments of the present invention are given for the purpose of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. A control system for intelligent material distribution and intelligent sorting, characterized in that: Including MES system, RMS system, AGV system, ROB system and PLC control system; The MES system, as the information management layer, is responsible for the execution of production plans, process recipe management, real-time monitoring, data collection and analysis; The RMS system, as the central control management layer, is a bridge connecting the MES system, AGV system, and PLC control system. It is used for seamless connection between the downstream control management layer and the upstream information management layer, as well as the collaborative work, intelligent centralized control, and unified management of multiple PLC control systems and AGV systems. The PLC control system is used as the control management layer, specifically using Siemens PLC, and communicating with the RMS system using Ethernet, while communicating with the remote I / O station, RFID reader, and ROB system using PROFINET fieldbus.

2. A control system for intelligent material distribution and intelligent sorting according to claim 1, characterized in that: The MES system issues tasks to the RMS system, and the tasks include the formula batch number, formula ratio, feeding time, and feeding station of the antimony ingot raw materials.

3. A control system for intelligent material distribution and intelligent sorting according to claim 1, characterized in that: The remote I / O station detects the device status by detecting sensors.

4. A control system for intelligent material distribution and intelligent sorting according to claim 1, characterized in that: The RFID reader uses a Pepperl+Fuchs UHF read / write module to write the information of the antimony ingot raw materials in the tray into the RFID chip.

5. The control system for intelligent material distribution and intelligent sorting according to claim 1 is characterized in that: The ROB system uses a 3D vision camera to scan the position coordinates of the antimony ingot raw materials to be grabbed in the tray to guide the industrial robot to complete fully automatic and precise grabbing actions.

6. A control system for intelligent material distribution and intelligent sorting according to claim 5, characterized in that: The industrial robot grasping fixture adopts a cylinder grasping method and is equipped with a photoelectric sensor to detect whether the antimony ingot raw material falls. The solenoid valve of the industrial robot adopts a three-position five-way structure. When the gripper is suddenly powered off or gas is cut off, it will remain in the current state to ensure that the antimony ingot raw material will not fall.

7. A control system for intelligent material distribution and intelligent sorting according to claim 1, characterized in that: The material allocation principle of the incoming material station of the system is as follows: the number of incoming material stations must be designed to be greater than the types of raw material batches in the formula to ensure that each proportion of material has a tray placed at the incoming material station, and then the raw material batches with large proportion values ​​are allocated to a spare station in order of proportion value.

8. A control system for intelligent material distribution and intelligent sorting according to claim 7, characterized in that: According to the allocation principle, the system sets the incoming material station allocation subroutine by the PLC control system. Through the preset program, the raw material batch number issued by the MES system can be automatically allocated to the incoming material station, and the spare station can be allocated according to the optimal material pulling efficiency.

9. A control system for intelligent material distribution and intelligent sorting according to claim 8, characterized in that: When the PLC control system detects that the original material station is out of material, it will automatically call the AGV to transfer the required raw material batch from the raw material warehouse to the original material station. The specific operation is: the PLC control system decomposes the task according to the formula batch number and ratio relationship issued by the MES system, and automatically plans the raw material batch number required for the incoming material station, and calls the AGV for fully automatic material transfer.

10. A control method for intelligent material distribution and intelligent sorting, applied to a control system for intelligent material distribution and intelligent sorting as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1. The MES system specifies and issues task requirements, including the formula and ratio of antimony ingot raw materials, feeding time, and feeding station; S2, after receiving the task, the RMS system transfers it to the PLC control system of the designated control layer; S3, PLC control system decomposes tasks according to the formula batch number and ratio relationship, automatically calculates the feeding task queue, and automatically plans the raw material batch number required for the incoming material station; S4, the PLC control system calls the AGV system to transport the required batches of antimony ingot raw materials to the incoming material station; S5, the PLC control system queries the currently required raw materials for feeding according to the feeding task queue of the upper system, and confirms the placement of the raw materials, that is, the robot picking station; S6, the PLC control system determines whether there is material on the tray in the target material-picking station, and if so, proceeds to step S8; if not, the PLC control system calls the AGV system to transport the required batch of antimony ingot raw materials to the incoming material station, and proceeds to step S7; S7, the PLC control system determines whether there is material on the pallet in the target standby material-retrieving station. If there is material, it proceeds to step S8; if there is no material, the PLC control system calls the AGV system to transport the required batch of antimony ingot raw materials to the incoming material station, and proceeds to step S6 for re-judgment; S8, the PLC control system sends the target material picking station and the target material feeding station to the industrial robot according to the current material feeding task; S9, the industrial robot moves to the top of the station tray according to the material picking station number specified by the PLC; S10, 3D vision scans the position coordinates of the antimony ingot raw materials in the tray and guides the robot to perform grabbing actions; S11. After the grabbing is completed, the PLC control system updates the data information of the raw materials in the pallet; S12, the industrial robot places the grabbed antimony ingot raw materials on the feeding platform according to the target feeding station specified by the PLC; S13, the pushing mechanism of the feeding platform pushes the antimony ingot raw materials into the combustion furnace for smelting; S14, when the current task is completed and the feeding time set by the upper system is reached, the next task is entered, and the cycle continues to step S5.

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