Lightweight model construction and state control method in PDM system

Abstract

The invention relates to a lightweight model construction and state control method in a PDM system. The method comprises the following steps: S1, initiating a lightweight conversion task of a digital model from the PDM system; s2, the lightweight conversion task is persisted to a database; s3, checking whether the lightweight conversion task scheduling is reasonable or not; s4, checking whether the lightweight conversion task is a timed task or not; s5, the lightweight conversion server analyzes the request task message, and each subtask initiates conversion; s6, downloading the original digital model; s7, transmitting lightweight conversion data to the lightweight conversion tool, and adding a corresponding request; reporting the heartbeat state to a lightweight transition server; s8, a JSON file in an agreed format is established, and the conversion tool server scans and analyzes data in the JSON file at regular time; s9, generating a lightweight model file, uploading the lightweight model file to a file warehouse, and inserting a JSON file scanning analysis result message into a message queue; s10, the lightweight conversion server receives a conversion result message asynchronously sent by the message queue, and analyzes the result message; and S11, realizing lightweight model unified management and control of the digital model at the BOM end.

Description

Technical Field

[0001] The invention relates to the field of PDM, and in particular to a lightweight model construction and state control method in a PDM system. Background Art

[0002] Fully three-dimensional digital models have become indispensable data in aircraft development. At present, a digital R&D system has been initially established in the field of aircraft design. In the development of multiple aircraft, full three-dimensional and online collaboration in the drawing process has been achieved, a closed-loop process for design changes has been established, the aircraft development status has been effectively controlled, and a comprehensive transformation from traditional two-dimensional drawings to fully three-dimensional digital aircraft development has been achieved.

[0003] However, the full three-dimensional original digital model generated by the current design is directly used for design, simulation, and support, and it still has its limitations. Specifically, the original design digital model contains a lot of design process information, the model data volume is large, and the computer cannot support simulation applications involving complex compartments or complex systems. Therefore, it is necessary to lightweight the original design digital model in order to effectively support the design applications of various disciplines. The traditional lightweight processing method is:

[0004] 1) When the amount of lightweight data is not large, designers handle it by themselves, but because of different methods, the data format of the lightweight model after processing is not unified, the compatibility is poor, and the reuse rate is low.

[0005] 2) When lightweighting the entire machine, the IT department uses local batch processing tools to download the design digital model to the computer and then perform lightweight batch processing of the entire machine digital model.

[0006] Both methods use offline processing, and the resulting lightweight prototype is separated from the original digital prototype in PDM. When the design status of aircraft components changes frequently, it is easy to cause deviations in the data status and accuracy of the lightweight model in actual applications and the consistency with the original digital prototype status.

[0007] Therefore, the use of online lightweight processing can solve the problem of consistency deviation of digital-analog design status caused by offline processing. At the same time, the data scheduling system can be used to improve the real-time performance of data processing and support a variety of complex business models at the time. Summary of the invention

[0008] Purpose of the present invention:

[0009] A method for lightweight model construction and state control in PDM system is proposed, which realizes the unified management, application and service of lightweight digital prototype model based on model EBOM, and supports the application demand of lightweight digital prototype model with unified state in model development.

[0010] The technical solution of the present invention:

[0011] A lightweight model construction and state control method in a PDM system includes the following steps:

[0012] Step S1: Initiate a lightweight manual or timed automatic conversion task of the digital model from the PDM system according to the conversion rules;

[0013] Step S2: persist the lightweight conversion task to the database;

[0014] Step S3: Verify whether the lightweight conversion task scheduling is reasonable according to the unified data access control strategy;

[0015] Step S4: Check whether the lightweight conversion task is a scheduled task. If it is a scheduled task, send the task message to the message queue after it is triggered at the scheduled time point, otherwise send the message to the message queue immediately;

[0016] Step S5: The lightweight conversion server receives the conversion request task message sent asynchronously from the message queue, parses the request task message, splits the task into multiple subtasks according to the CI configuration item as the basic unit, and calls the lightweight conversion tool for each subtask to initiate conversion;

[0017] Step S6: downloading the original digital model according to the original digital model address;

[0018] Step S7: The conversion tool server calls the lightweight conversion tool through the command line mode, passes the lightweight conversion data with CI configuration items as basic units to the lightweight conversion tool, and adds corresponding requests according to the lightweight conversion completion result; the conversion tool server periodically reports the heartbeat status to the lightweight conversion server to realize the status monitoring of the conversion tool server;

[0019] Step S8: The conversion tool server creates a JSON file in a specified format at the original digital model address. The conversion tool server periodically scans and parses the data in the JSON file according to the corresponding scanning configuration and performs subsequent processing.

[0020] Step S9: Generate a lightweight model file and upload it to the file warehouse, and insert the scan and parsing result message of the JSON file into the message queue;

[0021] Step S10: the lightweight conversion server receives the conversion result message sent asynchronously by the message queue, parses the result message, writes the conversion result into the lightweight soft attribute table, and stores it back to the PDM system;

[0022] Step S11: realizing unified management and control of lightweight models of digital models on the BOM side.

[0023] Furthermore, in step 1, a lightweight manual or timed automatic conversion task of the digital model is initiated from the PDM system, wherein the rules for manually initiating the conversion model within a specified time period from the PDM system are as follows:

[0024] (1) The lightweight model of the CI node does not need to be converted separately. The conversion of its associated DSI is initiated directly through validity. The user can select the conversion format and check multiple default precisions, or enter the precision; the lightweight conversion task of the DSI node corresponding to the current CI node is persisted in the database;

[0025] (2) When converting nodes above CI, the user inputs the validity filter PBS structure and selects the conversion format, conversion accuracy, validity, and conversion method: the lightweight conversion tasks corresponding to all DSI nodes within the context of the selected node are persisted in the database;

[0026] (3) Low-order lightweight model conversion rules: The low-order lightweight model is generated by the high-order lightweight model, that is, the generated high-order lightweight model is converted to generate a new low-order lightweight model;

[0027] (4) Conversion rules for converted lightweight models

[0028] Rule 1: If the components under DSI are changed, it is allowed to repeatedly initiate lightweight conversion of existing precision;

[0029] Rule 2: If the components under DSI are in an unpublished state, lightweight conversion is not allowed;

[0030] Rule 3: In the same flight interval, the lightweight model of the same version with the same accuracy in the same flight interval cannot be manually triggered;

[0031] The rules for automatically initiating the conversion model of a specified time period from the PDM system are as follows:

[0032] (1) Use the transaction log of the database to capture the rows that have been changed in the current time period, and directly use the parts filtered out in the transaction log as the part numbers modified in the specified time period;

[0033] (2) Recursively search the component sets associated with the model modified in the specified time period, search upward according to the component structure relationship, and obtain the CI node set of the components associated with the model modified in the specified time period; if an obsolete or terminated parent node appears in the process of searching the CI in the upper layer, find that its parent is valid and uses the version of the current child, and continue to recurse upward until the CI level, all recursive nodes are not in the obsolete or terminated state; filter according to the found CI list, when a CI node is not within the range of the incremental synchronous conversion model, it is excluded from the incremental synchronous conversion range; if the CI item in the CI list is repeated with the CI item in the top-level structure manually initiated by the user, it is excluded from the incremental synchronous conversion range; if the CI item in the CI list is repeated, it is deduplicated; after the data exclusion is completed, all CIs of the same model for incremental lightweight conversion are included in the same lightweight conversion request for lightweight conversion processing;

[0034] (3) Traverse the CI nodes in the CI list one by one: starting from each CI node level, find the DSI node from the CI node, and traverse the components layer by layer based on the EPM object structure associated with the DSI node to obtain the original digital model; if the DSI has no associated EPM object, skip it; if the EPM object status of the component node is obsolete or terminated, obtain the last valid version;

[0035] For CIs of models that are converted manually or automatically within a specified time period from the PDM system, it is necessary to traverse the child nodes to ensure that all components are in the unchecked state. Otherwise, the CI data in the unchecked state is recorded in the conversion log and the conversion is reinitiated during the next incremental synchronization.

[0036] Furthermore, in step 5, the parameters for calling the conversion tool include the original digital model address, the conversion instruction unique identifier, the organizational relationship file of the original digital model, the conversion format, the conversion accuracy, and whether it is the top level.

[0037] Further, in step 10, the information of the lightweight soft attribute table includes: component ID, validity, expiration time, csv file address link, lightweight model file address link, precision value and conversion format; the coding and name identification of the lightweight model are automatically generated by the lightweight conversion server, and the generation rules, in addition to being related to the associated component object coding, need to add a serial number.

[0038] Furthermore, in step 11, unified management and control of lightweight models of digital models including lightweight model version management is implemented on the BOM side.

[0039] Lightweight model version management rules:

[0040] 1) The major version of the lightweight model is consistent with the major version of DSI: When the DSI version is changed, the lightweight model initiates the conversion and keeps in sync with the changed version of DSI;

[0041] 2)DSI upgrades to a smaller version, the lightweight model initiates the conversion to the default precision and upgrades the lightweight model to a smaller version;

[0042] 3) Each DSI minor version is successfully converted once to generate a lightweight model minor version, and the converted lightweight model minor version corresponds to the current DSI minor version.

[0043] Furthermore, in step S5, when the requested task field needs to be extended, an abstract interface is designed, and a reflection mechanism is used to instantiate a data object class from the configuration, dynamically call the object, reduce code refactoring, and provide a function for verifying the consistency of data objects.

[0044] Further, step S6: using the model library management, when the lightweight conversion server initiates the general scheduling task, it uniformly downloads the original digital models related to all tasks, and caches the original digital models of related tasks by establishing a shared disk.

[0045] Further, step S7: by implementing multi-instance deployment of the conversion tool server, the scheduling weight is used to achieve load balancing. The specific load balancing algorithm is:

[0046] (1) Calculate the minimum completion time MinTi of all CI conversion tasks based on the number of parts N and the total size weight under CI;

[0047] (2) sort all CI conversion tasks in ascending order to form a queue L;

[0048] (3) Traverse all CI transformation tasks;

[0049] (4) Select the conversion tool server with the lowest current usage rate;

[0050] (5) Calculate the average completion time ACT and standard deviation SD of all CI conversion tasks based on the minimum completion time MinTi:

[0051]

[0052] Where n represents the total number of CI conversion tasks, and i is the current CI conversion task;

[0053] (6) If ACT < SD, it means that the lengths of all tasks in queue L are within a small range, so the next task is selected from the head of the queue in order; otherwise, the next task is selected from the tail of the queue in order;

[0054] (7) Delete the task assigned in (6) from queue L;

[0055] (8) If there are still tasks in queue L, go back to (4) until there are no tasks in queue L.

[0056] End the traversal.

[0057] Furthermore, for steps S7 and S10, after the current task scheduling or callback times out, the lightweight conversion server is directly notified of the task timeout; by adding a cluster fuse mechanism, when the current conversion tool server times out or an error occurs, the scheduling weight of the conversion tool server is dynamically reduced until it reaches zero, the fuse node is recorded, and a tentative task is sent at a certain interval. If no timeout occurs, the scheduling weight of the conversion tool server is increased or reduced until it is restored to the initial weight.

[0058] Beneficial effects of the present invention

[0059] The present invention proposes a lightweight model construction and state control method in a PDM system. By establishing a lightweight digital model online construction and management system, online lightweight incremental synchronous conversion, manual conversion and PDM BOM end lightweight state control processing methods are adopted to solve the problem of digital model design state consistency deviation caused by offline processing, and the unified control, application and service of the lightweight digital prototype model based on the model EBOM are realized, supporting the application demand for a lightweight digital prototype model with a unified state in model development. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A unified data management diagram of a lightweight digital model fused with EBOM in PDM provided by an embodiment of the present invention Figure 1 ;

[0061] Figure 2 A unified data management diagram of a lightweight digital model fused with EBOM in PDM provided by an embodiment of the present invention Figure 2 ;

[0062] like Figure 1 , 2 As shown, unified digital-analog management and control is achieved on the BOM side, the lightweight digital-analog major version is consistent with the DSI major version, and each DSI minor version is successfully converted once to generate a lightweight digital-analog minor version. The converted lightweight digital-analog minor version corresponds to the current DSI minor version.

[0063] Figure 3 A schematic diagram of a model conversion process provided by an embodiment of the present invention Figure 1 .like Figure 3 As shown, it means that the model transformation is initiated from CI;

[0064] Figure 4 A schematic diagram of a model conversion process provided by an embodiment of the present invention Figure 2 .like Figure 4 As shown, it indicates that the model conversion is initiated from the system;

[0065] Figure 5 A schematic diagram of a model conversion process provided by an embodiment of the present invention Figure 3 .like Figure 5 As shown, it indicates that the model conversion is initiated from the cabin.

[0066] Figure 6 A schematic diagram of the entire lightweight conversion process provided by an embodiment of the present invention. Figure 6 As shown, when the user requests the sender to check in the special parts in the PDM system, the PDM system automatically calls the automatic conversion interface, or manually triggers the conversion of a certain node (such as machine model, system, subsystem, CI); the PDM system receives the conversion request and performs a series of operations.

[0067] Figure 7 A schematic diagram of obtaining a CI node set of an update component provided by an embodiment of the present invention. Figure 7 As shown, the component collection associated with the model is modified according to the specified synchronization time period, and recursion is performed respectively, and the upper layer is searched according to the component structure relationship to obtain the CI node collection that uses the updated component.

[0068] Figure 8 Lightweight scheduling provided by the embodiment of the present invention Figure 1 .like Figure 8 As shown, the conversion rules of low-order lightweight models are shown when there is a generated corresponding CI high-order lightweight model.

[0069] Fig. 9 Lightweight scheduling provided by the embodiment of the present invention Figure 2 .like Fig. 9 As shown, the converted lightweight model conversion rules are shown.

[0070] Fig.10 A schematic diagram of the coding serial number generation rules provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0071] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0072] One embodiment of the present invention is: a method for lightweight model construction and state control in a PDM system to solve the technical problem that there is a lack of a data lightweight system that supports quasi-real-time lightweight model construction and state control in heterogeneous PDM systems in the prior art. The method comprises the following steps:

[0073] Step 1: Initiate a lightweight manual or scheduled automatic conversion task of the digital model from the PDM system according to the conversion rules;

[0074] Step 2: Send the lightweight conversion task to the message queue;

[0075] Step 3: The lightweight conversion server receives the conversion request task message sent asynchronously from the message queue, parses the request task message, splits the task into multiple subtasks based on the CI configuration item as the basic unit, and calls the lightweight conversion tool for each subtask to initiate conversion;

[0076] Step 4: Download the original digital model according to the original digital model address;

[0077] Step 5: The conversion tool server calls the lightweight conversion tool through the command line, passes the lightweight conversion data with CI configuration items as basic units to the lightweight conversion tool, and appends the corresponding request according to the lightweight conversion completion result;

[0078] Step 6: The conversion tool server creates a JSON file in a specified format under the original digital model address. The conversion tool server periodically scans and parses the data in the JSON file according to the corresponding scanning configuration and sends it to the lightweight conversion server;

[0079] Step 7: The lightweight conversion server receives the conversion result message sent asynchronously by the message queue, parses the result message, writes the conversion result into the lightweight soft attribute table, and stores it back to the PDM system;

[0080] Step 8: Implement unified management and control of lightweight models of digital models on the PDM BOM side.

[0081] A second embodiment of the present invention provides a lightweight model construction and state control method in a PDM system, comprising the following steps:

[0082] Step S1: Initiate a lightweight manual or timed automatic conversion task of a digital model from the PDM system, wherein the rules for manually initiating a conversion model within a specified time period from the PDM system are as follows:

[0083] (1) The lightweight model of the CI node does not need to be converted separately. The conversion of its associated DSI is initiated directly through validity. The user can select the conversion format and check multiple default precisions, or enter the precision; the lightweight conversion task of the DSI node corresponding to the current CI node is persisted in the database; CI is a configuration item, DSI is a design instance, and PDM system is a product data management system.

[0084] (2) When converting nodes above CI, the user inputs the validity filter PBS structure and selects the conversion format, conversion accuracy, validity and conversion method: the lightweight conversion tasks corresponding to all DSI nodes within the context of the selected node are persisted in the database; where PBS is a structure tree composed of CI configuration items.

[0085] (3) Low-order lightweight model conversion rules: The low-order lightweight model is generated by the high-order lightweight model, that is, the generated high-order lightweight model is converted to generate a new low-order lightweight model;

[0086] (4) Conversion rules for converted lightweight models

[0087] Rule 1: If the components under DSI are changed, it is allowed to repeatedly initiate lightweight conversion of existing precision;

[0088] Rule 2: If the components under DSI are in an unpublished state, lightweight conversion is not allowed;

[0089] Rule 3: In the same flight interval, the lightweight model of the same version with the same accuracy in the same flight interval cannot be manually triggered;

[0090] The rules for automatically initiating the conversion model of a specified time period from the PDM system are as follows:

[0091] (1) Use the transaction log of the database to capture the rows that have been changed in the current time period, and directly use the parts filtered out in the transaction log as the part numbers modified in the specified time period;

[0092] (2) Recursively search the component sets associated with the model modified in the specified time period, search upward according to the component structure relationship, and obtain the CI node set of the components associated with the model modified in the specified time period; if an obsolete or terminated parent node appears in the process of searching the CI in the upper layer, find that its parent is valid and uses the version of the current child, and continue to recurse upward until the CI level, all recursive nodes are not in the obsolete or terminated state; filter according to the found CI list, when a CI node is not within the range of the incremental synchronous conversion model, it is excluded from the incremental synchronous conversion range; if the CI item in the CI list is repeated with the CI item in the top-level structure manually initiated by the user, it is excluded from the incremental synchronous conversion range; if the CI item in the CI list is repeated, it is deduplicated; after the data exclusion is completed, all CIs of the same model for incremental lightweight conversion are included in the same lightweight conversion request for lightweight conversion processing;

[0093] (3) Traverse the CI nodes in the CI list one by one: starting from each CI node level, find the DSI node from the CI node, and traverse the components layer by layer based on the EPM object structure associated with the DSI node to obtain the original digital model; if the DSI has no associated EPM object, skip it; if the EPM object status of the component node is invalid or terminated, obtain the previous valid version.

[0094] Step S2: persist the lightweight conversion task to the database;

[0095] Step S3: Verify whether the lightweight conversion task scheduling is reasonable according to the unified data access control strategy;

[0096] Step S4: Check whether the lightweight conversion task is a scheduled task. If it is a scheduled task, send the task message to the message queue after it is triggered at the scheduled time point, otherwise send the message to the message queue immediately;

[0097] Step S5: The lightweight conversion server receives the conversion request task message sent asynchronously from the message queue, parses the request task message, splits the task into multiple subtasks according to the CI configuration item as the basic unit, and calls the lightweight conversion tool for each subtask to initiate conversion;

[0098] Step S6: downloading the original digital model according to the original digital model address;

[0099] Step S7: The conversion tool server calls the lightweight conversion tool through the command line mode, passes the lightweight conversion data with CI configuration items as basic units to the lightweight conversion tool, and adds corresponding requests according to the lightweight conversion completion result; the conversion tool server periodically reports the heartbeat status to the lightweight conversion server to realize the status monitoring of the conversion tool server;

[0100] Step S8: The conversion tool server creates a JSON file in a specified format at the original digital model address. The conversion tool server periodically scans and parses the data in the JSON file according to the corresponding scanning configuration and performs subsequent processing.

[0101] Step S9: Generate a lightweight model file and upload it to the file warehouse, and insert the scan and parsing result message of the JSON file into the message queue;

[0102] Step S10: the lightweight conversion server receives the conversion result message sent asynchronously by the message queue, parses the result message, writes the conversion result into the lightweight soft attribute table, and stores it back to the PDM system;

[0103] Step S11: realizing unified management and control of lightweight models of digital models on the PDM BOM side.

[0104] In this embodiment, for step S1: for the CI of the conversion model that is manually or automatically initiated from the PDM system for a specified time period, it is necessary to traverse the child nodes to ensure that all components are in an undetected state. Otherwise, the CI data in the undetected state will be recorded in the conversion log, and the conversion will be re-initiated during the next incremental synchronization.

[0105] In this embodiment, for step S5, the parameters for calling the conversion tool include the original digital model address, the unique identifier of the conversion instruction, the organizational relationship file of the original digital model, the conversion format, the conversion accuracy, and whether it is top-level. When the requested task field needs to be extended, an abstract interface is designed, and the reflection mechanism is used to instantiate the data object class from the configuration, dynamically call the object, reduce code refactoring, and provide the function of verifying the consistency of the data object.

[0106] In this embodiment, for step S6, model library management is used, and when the lightweight conversion server initiates the general scheduling task, the original digital models related to all tasks are downloaded uniformly, and the original digital models of related tasks are cached by establishing a shared disk.

[0107] In this embodiment, for step S7, multiple instances of the conversion tool server are deployed and the weight is scheduled to achieve load balancing. The specific load balancing algorithm is:

[0108] (9) Calculate the minimum completion time MinTi of all CI conversion tasks according to the number of parts N and the total size weight under CI;

[0109] (10) sorting all CI conversion tasks in ascending order to form a queue L;

[0110] (11) Traverse all CI transformation tasks;

[0111] (12) selecting a conversion tool server with the lowest current usage rate;

[0112] (13) Calculate the average completion time ACT and standard deviation SD of all CI conversion tasks based on the minimum completion time MinTi:

[0113]

[0114] Where n represents the total number of CI conversion tasks, and i is the current CI conversion task;

[0115] (14) If ACT < SD, it means that the lengths of all tasks in queue L are within a small range, so the next task is selected from the head of the queue in order; otherwise, the next task is selected from the tail of the queue in order;

[0116] (15) Delete the task assigned in (6) from queue L;

[0117] (16) If there are still tasks in queue L, go back to (4) until there are no tasks in queue L, and then end the traversal.

[0118] In this embodiment, for steps S7 and S10, after the current task scheduling or callback times out, the lightweight conversion server is directly notified of the task timeout; by adding a cluster fuse mechanism, when the current conversion tool server times out or an error occurs, the scheduling weight of the conversion tool server is dynamically reduced until it is zero, the fuse node is recorded, and a tentative task is sent at a certain interval. If no timeout occurs, the scheduling weight of the conversion tool server is increased or reduced until it is restored to the initial weight.

[0119] The above is only a specific embodiment of the present invention, and the present invention is described in detail. The unexplained part is a conventional technology. However, the protection scope of the present invention is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A lightweight model construction and state control method in a PDM system, characterized in that: The following steps are involved: Step S1: Initiate a lightweight manual or timed automatic conversion task of the digital model from the PDM system according to the conversion rules; Step S2: persist the lightweight conversion task to the database; Step S3: Verify whether the lightweight conversion task scheduling is reasonable according to the unified data access control strategy; Step S4: Check whether the lightweight conversion task is a scheduled task. If it is a scheduled task, send the task message to the message queue after it is triggered at the scheduled time point, otherwise send the message to the message queue immediately; Step S5: The lightweight conversion server receives the conversion request task message sent asynchronously from the message queue, parses the request task message, splits the task into multiple subtasks according to the CI configuration item as the basic unit, and calls the lightweight conversion tool for each subtask to initiate conversion; Step S6: downloading the original digital model according to the original digital model address; Step S7: The conversion tool server calls the lightweight conversion tool through the command line mode, passes the lightweight conversion data with CI configuration items as basic units to the lightweight conversion tool, and adds corresponding requests according to the lightweight conversion completion result; the conversion tool server periodically reports the heartbeat status to the lightweight conversion server to realize the status monitoring of the conversion tool server; Step S8: The conversion tool server creates a JSON file in a specified format at the original digital model address. The conversion tool server periodically scans and parses the data in the JSON file according to the corresponding scanning configuration and performs subsequent processing. Step S9: Generate a lightweight model file and upload it to the file warehouse, and insert the scan and parsing result message of the JSON file into the message queue; Step S10: the lightweight conversion server receives the conversion result message sent asynchronously by the message queue, parses the result message, writes the conversion result into the lightweight soft attribute table, and stores it back to the PDM system; Step S11: realizing unified management and control of lightweight models of digital models on the BOM side.

2. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: In step 1, a lightweight manual or timed automatic conversion task of the digital model is initiated from the PDM system, wherein the rules for manually initiating the conversion model within a specified time period from the PDM system are as follows: (1) The lightweight model of the CI node does not need to be converted separately. The conversion of its associated DSI is initiated directly through validity. The user can select the conversion format and check multiple default precisions, or enter the precision; the lightweight conversion task of the DSI node corresponding to the current CI node is persisted in the database; (2) When converting nodes above CI, the user inputs the validity filter PBS structure and selects the conversion format, conversion accuracy, validity, and conversion method: the lightweight conversion tasks corresponding to all DSI nodes within the context of the selected node are persisted in the database; (3) Low-order lightweight model conversion rules: The low-order lightweight model is generated by the high-order lightweight model, that is, the generated high-order lightweight model is converted to generate a new low-order lightweight model; (4) Conversion rules for converted lightweight models Rule 1: If the components under DSI are changed, it is allowed to repeatedly initiate lightweight conversion of existing precision; Rule 2: If the components under DSI are in an unpublished state, lightweight conversion is not allowed; Rule 3: In the same flight interval, the lightweight model of the same version with the same accuracy in the same flight interval cannot be manually triggered; The rules for automatically initiating the conversion model of a specified time period from the PDM system are as follows: (1) Use the transaction log of the database to capture the rows that have been changed in the current time period, and directly use the parts filtered out in the transaction log as the part numbers modified in the specified time period; (2) Recursively search the component sets associated with the model modified in the specified time period, search upward according to the component structure relationship, and obtain the CI node set of the components associated with the model modified in the specified time period; if an obsolete or terminated parent node appears in the process of searching the CI in the upper layer, find that its parent is valid and uses the version of the current child, and continue to recurse upward until the CI level, all recursive nodes are not in the obsolete or terminated state; filter according to the found CI list, when a CI node is not within the range of the incremental synchronous conversion model, it is excluded from the incremental synchronous conversion range; if the CI item in the CI list is repeated with the CI item in the top-level structure manually initiated by the user, it is excluded from the incremental synchronous conversion range; if the CI item in the CI list is repeated, it is deduplicated; after the data exclusion is completed, all CIs of the same model for incremental lightweight conversion are included in the same lightweight conversion request for lightweight conversion processing; (3) Traverse the CI nodes in the CI list one by one: starting from each CI node level, find the DSI node from the CI node, and traverse the components layer by layer based on the EPM object structure associated with the DSI node to obtain the original digital model; if the DSI has no associated EPM object, skip it; if the EPM object status of the component node is obsolete or terminated, obtain the last valid version; For CIs of models that are converted manually or automatically within a specified time period from the PDM system, it is necessary to traverse the child nodes to ensure that all components are in the unchecked state. Otherwise, the CI data in the unchecked state is recorded in the conversion log and the conversion is reinitiated during the next incremental synchronization.

3. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: In step 5, the parameters for calling the conversion tool include the original digital model address, the conversion instruction unique identifier, the organizational relationship file of the original digital model, the conversion format, the conversion accuracy, and whether it is the top level.

4. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: In step 10, the information of the lightweight soft attribute table includes: component ID, validity, expiration time, csv file address link, lightweight model file address link, precision value and conversion format; the coding and name identification of the lightweight model are automatically generated by the lightweight conversion server. In addition to being related to the associated component object coding, the generation rules need to add a serial number.

5. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: In step 11, unified management and control of lightweight models of digital models including lightweight model version management is implemented on the BOM side. Lightweight model version management rules: 1) The major version of the lightweight model is consistent with the major version of DSI: When the DSI version is changed, the lightweight model initiates the conversion and keeps in sync with the changed version of DSI; 2)DSI upgrades to a smaller version, the lightweight model initiates the conversion to the default precision and upgrades the lightweight model to a smaller version; 3) Each DSI minor version is successfully converted once to generate a lightweight model minor version, and the converted lightweight model minor version corresponds to the current DSI minor version.

6. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: In step S5, when the requested task field needs to be extended, an abstract interface is designed, and the reflection mechanism is used to instantiate the data object class from the configuration, dynamically call the object, reduce code refactoring, and provide the function of verifying the consistency of the data object.

7. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: Step S6: Using the model library management, when the lightweight conversion server initiates the general scheduling task, it uniformly downloads the original digital models related to all tasks, and caches the original digital models of related tasks by establishing a shared disk.

8. The lightweight model construction and state control method in the PDM system according to claim 1 is characterized in that: Step S7: By implementing multi-instance deployment of the conversion tool server, the scheduling weight is used to achieve load balancing. The specific load balancing algorithm is: (1) Calculate the minimum completion time MinTi of all CI conversion tasks based on the number of parts N and the total size weight under CI; (2) sort all CI conversion tasks in ascending order to form a queue L; (3) Traverse all CI transformation tasks; (4) Select the conversion tool server with the lowest current usage rate; (5) Calculate the average completion time ACT and standard deviation SD of all CI conversion tasks based on the minimum completion time MinTi: Where n represents the total number of CI conversion tasks, and i is the current CI conversion task; (6) If ACT < SD, it means that the lengths of all tasks in queue L are within a small range, so the next task is selected from the head of the queue in order; otherwise, the next task is selected from the tail of the queue in order; (7) Delete the task assigned in (6) from queue L; (8) If there are still tasks in queue L, go back to (4) until there are no tasks in queue L. End the traversal.

9. The lightweight model construction and state control method in the PDM system according to claim 1, characterized in that: For steps S7 and S10, after the current task scheduling or callback times out, the lightweight conversion server is directly notified of the task timeout; by adding a cluster fuse mechanism, when the current conversion tool server times out or an error occurs, the scheduling weight of the conversion tool server is dynamically reduced until it reaches zero, the fuse node is recorded, and a tentative task is sent at a certain interval. If no timeout occurs, the scheduling weight of the conversion tool server is increased or reduced until it is restored to the initial weight.

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