Workshop scheduling method oriented to tray-workbench binding and clamping flexibility

Abstract

The invention discloses a flexible workshop scheduling method for tray-workbench binding and clamping, and belongs to the technical field of flexible manufacturing and intelligent scheduling. In consideration of a mapping relation between a tray and a workbench and a flexible difference problem of clamping time involved in actual production, a scheduling model fusing processing equipment, the workbench and the tray is constructed, and a constraint relation between resource occupation and process execution is established. In order to improve the feasibility and flexibility of scheduling, a feasible insertion judgment model under multi-resource conflict verification is provided, and task insertion and resource state updating are dynamically completed in combination with process priority, resource time window feasibility, sequential logic and tray conflict judgment. The method provides a model basis and a modeling means for realizing efficient operation and resource utilization optimization of a manufacturing system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of workshop production scheduling, in particular to a workshop scheduling modeling method considering the binding relationship between pallets and workbenches and clamping flexibility, and belongs to the technical field of advanced manufacturing system modeling and control. BACKGROUND

[0002] The flexible job shop scheduling problem is a key link in the intelligent manufacturing system, and widely exists in the discrete production system with multi-process, multi-device and multi-resource coordination. The existing scheduling model mainly focuses on the optimization of processing path and device allocation, but lacks systematic modeling of non-processing links such as clamping, unloading and transportation, resulting in insufficient adaptability and executability of the model in complex and real production environment.

[0003] In the processing scene requiring precise clamping, the time cost of the clamping process and its occupation of resources have a significant impact. The differences in structure, precision and operation mode of different workbenches result in flexible clamping time, and further form multiple constraint relationships between clamping operation and workbenches. At the same time, as a physical carrying resource in the clamping link, the pallet usually has a binding relationship with a specific type of workbench, and the number of pallets is limited, so the use sequence and release time of the pallets will directly affect the schedulability and production rhythm of the process. The existing scheduling modeling method rarely considers the constraint limitations of pallets and workbenches, and does not fully depict the flexible variation of clamping time. In the face of complex scenes such as multi-process coordination, multi-pallet resource allocation and continuous occupation of resources, it is difficult to achieve high-precision modeling of the whole process and multi-resource coordination, thereby affecting the feasibility and execution efficiency of the scheduling strategy.

[0004] Therefore, there is an urgent need for a workshop scheduling optimization method considering the binding of pallets and workbenches and the flexibility of clamping, to improve the actual feasibility and running efficiency of the scheduling system. SUMMARY

[0005] The present application aims to improve scheduling efficiency and resource utilization, and proposes a workshop scheduling method considering the binding of pallets and workbenches and the flexibility of clamping, in view of the resource limitations of pallets and workbenches and the flexibility differences of clamping operation in the flexible job shop. The method fully considers the configuration state and occupation behavior of three types of resources, i.e. processing equipment, workbenches and pallets, and constructs a modeling structure conforming to the actual process flow and resource coordination logic. The method mainly includes: establishing a "clamping-processing-unloading" resource-task time relationship model, analyzing the multiple resource constraint limitations, constructing an optimization objective function minimizing the maximum completion time, and on the basis of preliminary scheduling, combining with the process priority mechanism and resource idle window information, constructing a feasible insertion judgment model under multi-resource conflict checking, to realize dynamic adjustment and performance optimization of the scheduling solution.

[0006] (1) Establish the resource-task time relationship model of "clamping-processing-unloading"

[0007] The method faces the typical scheduling scenario of flexible manufacturing workshop, and considers the dependence relationship of three types of core resources in the actual production process of workpieces, which are machining equipment, workbench and pallet resources. Each workpiece contains specific machining processes, and the execution of each process includes three consecutive stages: clamping, processing and unloading, which are completed by workbench, machining equipment and pallet throughout the whole process.

[0008] By analyzing the specific process of each machining stage and the different operating states in each process, the time factors in this state are determined. In the clamping stage, there is a waiting time T wt before clamping and a clamping time T w , in the processing stage, there is a waiting time T mt before processing and a processing time T m , in the unloading stage, there is a waiting time T ut before unloading and an unloading time T u The pallet is bound to the workbench at the beginning of clamping and remains occupied until the corresponding unloading operation is completed. Therefore, the pallet time starts to occupy from the beginning of T w and ends at the end of T u .

[0009] (2) Analysis of multi-resource constraint

[0010] To ensure the rationality and executability of the scheduling modeling, the collaborative relationship of multiple resources in the system and the scheduling assumption conditions are clarified. The workshop is composed of the following four elements: workpieces, machining equipment, workbenches and pallets. Each workpiece is composed of corresponding processes, and each process needs to complete clamping, processing and unloading in turn. It is considered that the workbench and machining equipment have sufficient buffer capacity and can be used for short task waiting.

[0011] Firstly, the start of any process must be based on the complete end of its previous process to ensure the continuity of the processing logic. Secondly, in the three-stage execution process, the use of various resources is limited to the optional set and the compatible set. The optional machining equipment set of the jth process of the ith workpiece is , the clamping optional workbench set is , the workbench corresponding optional pallet set is , and the unloading workbench available set is the pallet corresponding optional workbench set Due to differences in structure and operation methods, different workbenches have different clamping times when executing the same process, which constitutes a flexible clamping constraint. During the scheduling process, the scheduling system needs to select the most appropriate workbench resource to execute the corresponding process based on the optimal clamping time, resource availability, and pallet binding relationships.

[0012] The start time of each phase is not only constrained by the resource idle state, but also affected by the completion time of the previous phase. Therefore, the time difference requirements for each phase are as follows:

[0013] (1)

[0014] (2)

[0015] (3)

[0016] (4)

[0017] Due to the limited number of resources in the workshop and the high degree of resource sharing, in order to ensure the executability of the scheduling system and the independence of task execution, the system must strictly meet the resource mutual exclusion constraint, that is, at any time, the same resource can only be occupied by one process task. To this end, the present invention imposes clear time overlap restrictions on the occupancy periods of processing equipment, pallets, and workbenches to prevent the occurrence of overlapping resource use during the scheduling process, thereby avoiding resource conflicts that affect the continuity and feasibility of task execution. The specific constraint relationships are shown in formulas (5) to (8):

[0018] ,but (5)

[0019] like ,but (6)

[0020] like ,but (7)

[0021] like ,but (8)

[0022] In the resource utilization process, the present invention further considers resource inheritance logic. If adjacent processes of the same workpiece have compatible resource selections for pallets and workbenches, that is, they have the same pallet-workbench binding relationship, then the subsequent process is allowed to inherit and use the resource combination of the previous process, thereby saving clamping-unloading time, reducing the number of resource switching times, and improving the continuity of overall scheduling. The feasibility of the above resource inheritance is described by formulas (9) to (11), which clarify the inheritance and use judgment logic of pallets and workbenches under the conditions of temporal continuity and consistent combination:

[0023] If , then (9)

[0024] (10)

[0025] (11)

[0026] In addition, to improve the coordination efficiency of the scheduling system under limited resources, a scheduling priority mechanism is introduced, which prioritizes the scheduling of processes with a narrower range of available resources to reduce the overall system conflict probability.

[0027] (3) Construction of scheduling optimization objective model

[0028] Based on the construction of time and resource usage, a mathematical model of the flexible scheduling problem is established with the optimization objective of minimizing the maximum completion time. The model considers multiple feasibility constraints such as process execution order, equipment and workstation occupation, tray usage and binding restrictions, effectively improving the schedulability and insertion judgment efficiency of the scheduling system under strong coupling conditions of resources, and is suitable for complex scheduling environments in actual manufacturing systems with clamping-machining-unloading resource binding constraints.

[0029] The mathematical expression of the scheduling model is as follows:

[0030] (12)

[0031] (4) Feasible insertion optimization under multi-resource conflict checking

[0032] To further improve the response capability and overall efficiency of the scheduling system under resource shortage and process coupling conditions, the invention introduces process priority mechanism, phased resource feasibility exploration, operation logic verification, and tray conflict identification, forming a job shop scheduling optimization method considering tray-workstation binding and clamping flexibility. The determination model is divided into the following four sub-steps:

[0033] 1) Dynamic evaluation mechanism of process priority

[0034] The scheduling system first scores the priority of all unscheduled processes to determine the insertion attempt order. The priority considers two dimensions: the total number of subsequent machining paths and the number of available resources. The priority score of the jth process of the ith workpiece is defined as follows:

[0035] (13)

[0036] where ​is the adjustment coefficient, balancing the task urgency and resource tension.

[0037] 2) Multi-resource independent feasibility analysis model

[0038] For the target process to be scheduled, the system sequentially inserts the required resources for its three operation stages according to the priority from high to low. This process is based on the idle time window of each resource to determine whether there is enough insertion space before the current time.

[0039] For the process processing stage , let its candidate processing equipment set be , the system traverses each device in the set to find the feasible interval in its idle time set . If the following formula exists, it is considered that the insertion operation can be performed:

[0040] (14)

[0041] For the insertion in the clamping process, based on the candidate workstation set , traverse all workstations in its set to find the feasible interval . For the unloading process, based on the available workstation set , find the available workstation , and find the feasible interval in its idle time set . If the following formula is satisfied, it is considered that the insertion can be performed:

[0042] (15)

[0043] (16)

[0044] The above three judgments are independent of each other, and only the insertion feasibility of each resource before the current time is required. All stage insertion times are determined independently, and do not require continuity or alignment.

[0045] 3) Operation logic sequence and tray occupation relationship verification

[0046] After completing the feasibility test, the system performs a serial logic verification of the order of clamping, processing and unloading stages according to the process logic. Its basic logic is as follows:

[0047] (17)

[0048] That is, after ensuring the clamping should be later than the previous unload, the processing should be later than the clamping is completed, and the unload should be later than the processing is completed, the order logic enters the conflict judgment of the tray resource. If any condition is not met, it is judged as a time conflict, which is considered as not insertable.

[0049] After the sequence verification passes, the system further performs the occupation conflict judgment of the tray resource. Since the tray needs to be continuously bound between "clamping starts to unload is completed" and cannot be occupied by other processes at the same time, the system needs to check whether the candidate tray in the following occupation interval overlaps with the occupation period of other scheduling processes using the same tray. If there is an overlap, the current insertion is invalid, and the system first finds other compatible tray sets supported by the workbench of the current process , attempts to replace the tray to maintain the physical compatibility of clamping-unloading. If the alternative tray resource is also conflicted or does not exist, the insertion operation is not performed, and other feasible resource combinations are continued to be tried.

[0050] 4) Feasible insertion result confirmation and resource state synchronization

[0051] When a process passes through the priority judgment, the three-stage resource insertion trial, the operation sequence logic verification and the tray resource conflict judgment, it can be determined that the current insertion scheme has feasibility in the physical and timing levels. At this time, the system will perform resource occupation update operation, and update the free time set of the involved resources, including processing equipment, workbench and tray three types of resources, for subsequent task arrangement and use.

[0052] The symbols used in the mathematical model are as follows:

[0053]

[0054] The patent application is based on the formation of a workshop model considering tray-workbench binding and clamping flexibility, and a multi-resource scheduling structure is constructed which integrates resource selection, usage constraints and binding inheritance logic. By introducing the time state division of typical operation stages, the resource logic and time dependence relationship of process execution are clarified, a scheduling mathematical model is established with the optimization objective of minimizing the maximum completion time, and constraint conditions such as mutual exclusion of multiple resource usage, tray-workbench binding and resource quantity limitation are set. The model fully reflects the key elements and actual constraint relationships in the multi-resource flexible scheduling system, and provides a modeling basis for the solution of subsequent scheduling optimization method and the design of scheduling strategy. BRIEF DESCRIPTION OF DRAWINGS

[0055] The present application will be further described below in conjunction with the drawings and examples.

[0056] Figure 1 is the time state relationship of workbench, processing equipment, tray

[0057] Figure 2 is the logical relationship of three resource selection of workbench, processing equipment, tray DETAILED DESCRIPTION

[0058] The present application takes improving scheduling efficiency and resource utilization in actual manufacturing system as the target, combines the clamping flexibility difference existing in the discrete manufacturing process and the tray and workbench resource restriction, and designs a workshop scheduling modeling method suitable for the tray-workbench binding and clamping flexibility. The method comprehensively considers the occupation state and configuration relationship of three types of resources of processing equipment, workbench and tray in the production process, constructs the scheduling modeling structure conforming to the actual process logic, takes the minimum maximum completion time as the optimization target, establishes the resource-task time relationship model of "clamping-processing-unloading", analyzes the multiple resource constraint restrictions, constructs the optimization objective function of minimizing the maximum completion time, and on the basis of the preliminary scheduling, combines the process priority mechanism and resource idle window information, constructs the feasible insertion judgment model under the multi-resource conflict checking, realizes the dynamic adjustment and performance optimization of the scheduling solution. The implementation process of the present application is further described below in combination with the drawings and specific embodiments.

[0059] Step 1: Establishing the resource-task time relationship model of "clamping-processing-unloading"

[0060] The method faces the typical scheduling scene of flexible manufacturing workshop, considers the dependence relationship of workpieces on three types of core resources in the actual production process, which are processing equipment, workbench and tray resources. Each workpiece contains specific processing procedures, and the execution of each procedure includes three continuous stages: clamping, processing and unloading, which are completed by the workbench, processing equipment and the tray throughout the whole process.

[0061] The specific process of each processing stage is analyzed, the different operation states in each process are analyzed, and the time factors in the state are determined. In the clamping stage, there are clamping pre-waiting time (T wt ) and clamping time (T w ), in the processing stage, there are processing pre-waiting time (T mt ) and processing time (T m ), in the unloading stage, there are unloading pre-waiting time (T ut ) and unloading time (T u ), the tray is bound with the workbench at the beginning of clamping and keeps the occupation state until the corresponding unloading operation is completed, and cannot be changed or released during use, so the tray time starts to occupy from the beginning of T w , and ends at the end of T u . As shown in Figure 1 Figure 1 ​The occupancy relationship of clamping time, mounting time, unloading time and pallet occupancy time in the machining process is shown by two continuous processes of a workpiece.

[0062] Step 2: Analysis of multi-resource constraint restrictions

[0063] To ensure the rationality and executability of the scheduling model, the collaborative relationship of multiple resources in the system and the scheduling assumption conditions are clarified. The workshop is composed of the following four elements: workpieces, processing equipment, workbenches and pallets. Each workpiece is composed of corresponding processes, and each process needs to complete the clamping, processing and unloading stages in turn. It is considered that the workbenches and processing equipment have sufficient buffer capacity and can be used for short-term task waiting.

[0064] Firstly, the start of any process must be based on the complete end of its previous process to ensure the continuity of the processing logic. Secondly, during the three-stage execution process, the use of various resources is limited to the selectable set and the compatible set. The selectable processing equipment set of the jth process of the ith workpiece is , the clamping selectable workbench set is , the workbench corresponding selectable pallet set is , and the unloading workbench available set is the pallet corresponding selectable workbench set . Due to differences in structure and operation mode, different workbenches have different clamping times when executing the same process, forming a flexible clamping constraint. During scheduling, the scheduling system needs to select the most suitable workbench resource to execute the corresponding process based on the optimal clamping time consumption, resource idle state and pallet binding relationship.

[0065] The start time of each stage is not only subject to the resource idle state constraint, but also affected by the completion time of the previous stage operation. Therefore, the time difference requirements for each stage are as follows:

[0066] (1)

[0067] (2)

[0068] (3)

[0069] (4)

[0070] Figure 2Taking one process of the workpiece i as an example, the selection logic for different resources is displayed, and the results are displayed in the form of a Gantt chart. Since the number of resources in the workshop is limited and the sharing degree of resources is high, in order to ensure the executability of the scheduling system and the independence of task execution, the system needs to strictly meet the resource mutual exclusion constraint condition, that is, at any time, the same resource can only be occupied by one process task. Therefore, the application clearly limits the time overlap of the occupation period of the machining equipment, the tray and the workbench, prevents the overlapping use of resources during scheduling, and avoids the influence of resource conflicts on the continuity and feasibility of task execution, and the specific constraint relationship can be seen from formulas (5) to (8):

[0071] Then (5)

[0072] If Then (6)

[0073] If Then (7)

[0074] If Then (8)

[0075] In the resource use process, the application further considers the resource inheritance logic. If the resource selection of adjacent processes of the same workpiece to the tray and the workbench is compatible, that is, it has the same tray-workbench binding relationship, then the resource combination of the previous process is allowed to be inherited by the next process, thereby saving the clamping-unloading time, reducing the number of resource switching and improving the continuity of the overall scheduling. The feasibility of the above resource inheritance is described by formulas (9) to (11), which clearly describes the inheritance use judgment logic of the tray-workbench under the condition of time continuity and consistent combination:

[0076] If Then (9)

[0077] (10)

[0078] (11)

[0079] In addition, in order to improve the coordination efficiency of the scheduling system under limited resources, a scheduling priority mechanism is introduced, which preferentially schedules the processes with a narrower range of resource options, to reduce the conflict probability of the overall system.

[0080] Step 3: Construct a scheduling optimization objective model

[0081] Based on the construction time and resource utilization, a mathematical model for the flexible scheduling problem was established with the optimization objective of minimizing the maximum completion time. This model comprehensively considers feasibility constraints such as process execution sequence, equipment and workbench occupancy, pallet usage, and binding restrictions. It effectively improves the scheduling system's schedulability and insertion decision efficiency under conditions of strong resource coupling. It is applicable to the complex scheduling environments of actual manufacturing systems with setup-processing-unloading resource binding constraints.

[0082] The mathematical expression of the scheduling model is as follows:

[0083] (12)

[0084] Step 4: Determine feasible insertion optimization under multi-resource conflict verification

[0085] To improve the responsiveness and overall efficiency of the scheduling system under resource constraints and process coupling, the invention introduces multiple sub-processes, including a process priority mechanism, phased resource feasibility testing, operation logic verification, and pallet conflict identification, to form a shop floor scheduling adjustment mechanism for pallet-workbench binding and clamping flexibility. The judgment model is divided into the following four sub-steps:

[0086] (1) Dynamic evaluation mechanism of process priority

[0087] The scheduling system first scores the priority of all unscheduled processes to determine the insertion attempt order. The priority takes into account the total number of processes in its subsequent processing path. , and the number of optional resources. The priority score of the jth process of the i-th workpiece is The definition is as follows:

[0088] (13)

[0089] in To adjust the coefficient, balance the urgency of the task and the intensity of resources.

[0090] (2) Multi-resource independent feasibility analysis model

[0091] For the target process to be scheduled, the system conducts independent insertion feasibility tests for the resources required for its three operational phases, ranked from highest to lowest priority. This process uses the idle time window of each resource as a basis to determine whether there is sufficient space for insertion before the current moment.

[0092] For the processing stage , let the candidate processing equipment set be , the system traverses each device in the collection , gather in their free time Find the feasible interval in If the following formula exists, it is considered that the insertion operation can be performed:

[0093] (14)

[0094] For the insertion in the clamping process, based on the candidate workbench set , all workbenches in its set are traversed , and the feasible interval is searched in the free time set of each workbench ; for the unloading process, based on the available workbench set of the tray , the available workbench is searched , and the feasible interval is searched in the free time set of each workbench . If the following formula is satisfied, it is considered that the insertion can be performed:

[0095] (15)

[0096] (16)

[0097] The above three judgments are independent of each other, and only the insertion feasibility of the respective resources before the current time is required. The insertion time of all stages is determined independently, and there is no requirement for continuity or alignment.

[0098] (3) Operation logic sequence and tray occupation relationship verification

[0099] After the feasibility is verified, the system performs a serial logic verification on the order of the clamping, machining and unloading stages according to the process logic. The basic logic is as follows:

[0100] (17)

[0101] That is, after ensuring that the clamping should be later than the previous unloading, the machining should be later than the clamping completion, and the unloading should be later than the machining completion, the order logic is entered into the conflict judgment of the tray resource. If any condition is not met, it is determined as a time conflict, which is considered as not insertable.

[0102] After the order verification is passed, the system further performs the occupation conflict judgment of the tray resource. Since the tray needs to be continuously bound between “clamping starts to unloading completes” and cannot be occupied by other processes at the same time, the system needs to check whether the candidate tray in the following occupation interval overlaps with the occupation time period of the same tray used by other scheduling processes. If there is an overlap, the current insertion is invalid, the system first searches for other compatible tray sets supported by the selected workbench of the current process , and tries to replace the tray to maintain the physical compatibility of clamping-unloading. If the alternative tray resource is also in conflict or does not exist, the insertion operation is not performed, and other feasible resource combinations are continued to be tried.

[0103] (4) Feasible insertion result confirmation and resource state synchronization

[0104] When a certain process passes the aforementioned priority determination, three-stage resource insertion heuristic, operation sequence logic verification, and tray resource conflict determination, it can be determined that the current insertion scheme has feasibility in both physical and timing levels. At this time, the system will perform resource occupation update operation and update the free time set of the involved resources, including processing equipment, workbench, and tray, for subsequent task arrangement and use.

[0105] The symbols used in the mathematical model are as follows:

[0106]

Claims

1. A workshop scheduling method for flexible pallet-workbench binding and clamping, characterized by: Considering the mapping relationship between pallets and workbenches, and the differences in the flexibility of clamping operations under different resource configurations, a scheduling model integrating processing equipment, workbenches, and pallets was constructed. After completing the basic model through the first three steps, step four combines shop-specific issues, process priorities, resource time window feasibility, sequential logic, and pallet conflict judgment to complete task insertion and resource status updates to optimize and improve scheduling results. The specific implementation steps are as follows: Step 1: Establish a resource-task time relationship model of "clamping-processing-unloading"; This method targets typical scheduling scenarios in flexible manufacturing workshops and considers the dependencies of workpieces on three core resources during the actual production process: processing equipment, workbenches, and pallets. Each workpiece has a specific processing step, and the execution of each step consists of three consecutive phases: clamping, processing, and unloading, which are completed by the workbench, processing equipment, and pallets throughout the entire process. Analyze the specific process of each processing stage, analyze the different operating states in each process, determine the time factors in this state, and there is a waiting time T before clamping in the clamping stage. wt and clamping time T w , there is a waiting time T before processing in the processing stage mt and processing time T m , there is a waiting time T before unloading in the unloading phase ut and unloading time T u The pallet is bound to the workbench at the beginning of clamping and remains in the occupied state until the corresponding unloading operation is completed. It cannot be replaced or released during use. Therefore, the pallet time starts from T w The occupation starts at the start time of T u The occupation ends at the end time; Step 2: Analyze multiple resource constraints; To ensure the rationality and feasibility of scheduling modeling, the collaborative relationships and scheduling assumptions of multiple resource types are clarified. The workshop is composed of the following four elements: workpieces, processing equipment, workbenches, and pallets. Each workpiece is composed of corresponding processes, and each process must complete the three stages of clamping, processing, and unloading in sequence. It is assumed that the workbenches and processing equipment have sufficient buffering capacity for short-term task waiting. First, the start of any process must be based on the complete completion of its previous process to ensure the continuity of processing logic; Secondly, during the three-stage execution process, the use of various resources is limited to the optional set and the compatible set; the optional processing equipment set for the j-th process of the i-th workpiece is , the optional workbench set for clamping is , the workbench corresponds to the optional pallet set The available set of unloading workbenches is the set of optional workbenches corresponding to the pallet. ; Due to differences in structure and operation methods, different workbenches have different clamping times when performing the same process, which constitutes a flexible clamping constraint. During the scheduling process, the scheduling system selects the most suitable workbench resource to execute the corresponding process based on the optimal clamping time, resource availability, and pallet binding relationships. The start time of each stage is not only constrained by the idle state of resources, but also affected by the completion time of the previous stage operation; therefore, the time difference requirements for each stage are as follows: (1) (2) (3) (4) A process of workpiece i shows the logic of different resource selection and displays the results in the form of a Gantt chart. Clear time overlap restrictions are set for the occupancy periods of processing equipment, pallets, and workbenches to prevent overlapping resource use during the scheduling process, thereby avoiding resource conflicts that affect the continuity and feasibility of task execution. The specific constraint relationships are shown in formulas (5) to (8): ,but (5) like ,but (6) like ,but (7) like ,but (8) The resource inheritance logic is considered in the resource utilization process. If the adjacent processes of the same workpiece are compatible with the resource selection of the pallet and the workbench, that is, they have the same pallet-workbench binding relationship, then the subsequent process is allowed to inherit and use the resource combination of the previous process, thereby saving clamping-unloading time, reducing the number of resource switching times, and improving the continuity of the overall scheduling. The feasibility of the above resource inheritance is described by formulas (9) to (11), which clarify the inheritance judgment logic of the pallet-workbench under the conditions of time continuity and consistent combination: like ,but (9) (10) (11) In addition, to improve the coordination efficiency of the scheduling system under limited resources, a scheduling priority mechanism is introduced to prioritize the scheduling of processes with a narrower range of resource options, thereby reducing the overall probability of conflicts. Step 3: Construct a scheduling optimization target model; Based on the construction time and resource usage, a mathematical model for the flexible scheduling problem was established with the optimization goal of minimizing the maximum completion time. By comprehensively considering the feasibility constraints of process execution sequence, equipment and workbench occupancy, pallet usage, and binding restrictions, the scheduling system's schedulability and insertion judgment efficiency under conditions of strong resource coupling were improved. This model is applicable to complex scheduling environments with setup-processing-unloading resource binding constraints in actual manufacturing. The mathematical expression of the scheduling model is as follows: (12) Step 4: Determine the feasible insertion optimization under multi-resource conflict verification; In order to improve the responsiveness and overall efficiency of the scheduling system under the conditions of resource shortage and process coupling, multiple sub-processes including process priority mechanism, phased resource feasibility exploration, operation logic verification and pallet conflict identification were introduced to form a workshop scheduling adjustment mechanism for pallet-workbench binding and clamping flexibility.

2. The workshop scheduling method for flexible pallet-workbench binding and clamping according to claim 1, characterized in that: The decision model in step 4 is divided into the following four sub-steps: (1) Dynamic evaluation mechanism of process priority The scheduling system first prioritizes all unscheduled processes to determine the insertion attempt order; the priority takes into account the total number of processes in its subsequent processing path. , and the number of optional resources; the priority score of the jth process of the i-th workpiece The definition is as follows: (13) in To adjust the coefficient, balance the urgency of the task and the degree of resource constraints; (2) Multi-resource independent feasibility analysis model For the target process to be scheduled, the feasibility of independently inserting the resources required for its three operation stages is tested in descending order of priority. Based on the idle time window of each resource, it is determined whether there is sufficient space for insertion before the current moment. For the processing stage , let the candidate processing equipment set be , the scheduling system traverses each device in the collection , gather in their free time Find the feasible interval in , if the following formula exists, it is considered to be inserted: (14) For insertion during clamping, based on the candidate workbench set , iterate over all workbenches in its collection , gather in their free time Finding a feasible interval ; For unloading process, available workbench collection based on pallet , search for available workbenches , gather in their free time Find the feasible region in ; Insert if the following formula is met: (15) (16) The above three judgments are performed independently of each other, and only need to satisfy the feasibility of the insertion of each resource before the current time. The insertion time of each stage is determined independently and does not require continuity or alignment. (3) Verification of the operation logic sequence and pallet occupancy relationship After completing the feasibility test, the sequence of the clamping, processing, and unloading stages is verified in series logic according to the process logic; the basic logic is as follows: (17) After ensuring that clamping is later than the previous unloading, processing is completed later than clamping, and unloading is completed later than processing, the conflict judgment of pallet resources is entered. If any of the conditions is not met, it is determined to be a time conflict and cannot be inserted; After the sequence check is passed, the occupancy conflict judgment of the pallet resources is performed; check whether the candidate pallet overlaps with the occupancy period of the same pallet in other scheduling processes in the following occupancy interval; if there is an overlap, the current insertion is invalid, and first find other compatible pallet sets supported by the workbench selected by the current process , try to replace the pallet to maintain the physical compatibility of clamping and unloading; if the alternative pallet resource also conflicts or does not exist, do not insert the operation, and continue to try other feasible resource combinations; (4) Confirmation of feasible insertion results and synchronization of resource status; When a process passes the aforementioned priority determination, three-stage resource insertion trial, operation sequence logic verification, and pallet resource conflict judgment, it can be determined that the current insertion plan is feasible both physically and temporally. At this point, the resource occupancy update operation will be executed, and the idle time set of the resources involved will be updated, including three types of resources: processing equipment, workbenches, and pallets, in preparation for subsequent task scheduling.

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