A stamping process monitoring method based on intelligent waveform interception technology

Abstract

The present application belongs to the technical field of stamping equipment monitoring, and specifically discloses a stamping process monitoring method based on intelligent waveform interception technology. The present application first obtains template stamping data based on the average of multiple groups of normal product stamping data; then expands the template stamping data according to a preset tolerance to generate an alarm envelope curve; then uses the monitored stamping data to slide and update the observation window, and finds the stamping data with a valley value between the stamping data and the template stamping data in the observation window as the data of a single stamping. Finally, if the data of a single stamping exceeds the range of the alarm envelope curve, it is determined that the product of the single stamping is abnormal. The present application uses the data waveform of normal stamping as a template to intelligently intercept the continuous stamping data, and obtains the stamping data of each time, so that there is no need to add additional counting equipment to the stamping equipment, reducing the complexity and cost of the monitoring system.

Description

Technical Field

[0001] The present application belongs to the technical field of stamping equipment monitoring, and more specifically, to a stamping process monitoring method based on intelligent waveform interception technology. Background Art

[0002] In the machining industry, stamping is an important process step in sheet metal processing. The stamping process has abnormalities such as out-of-tolerance dimensions, positional offset of feature parts, irregular bending, missing holes, hole deformation, edge burrs / burrs, surface indentations, scratches, grinding marks, textures, etc., so the processing process needs to be monitored.

[0003] The strain / stress changes of the stamping equipment during the stamping process are highly correlated with the processing status of the processed products. Therefore, the processing status of the stamping products can be evaluated by monitoring the stamping waveform. If the processing status of each stamping product is to be accurately obtained, the stamping waveform corresponding to each stamping product must be separated from all stamping data for analysis. At present, in order to obtain the stamping waveform of each stamping product, a sensor device is usually installed on the stamping equipment to record each stamping, or each stamping is obtained from the IO output of the stamping equipment. These methods require the stamping equipment to be modified, which is relatively complicated and troublesome. Summary of the invention

[0004] In response to the above defects or improvement needs of the prior art, the present application provides a stamping process monitoring method based on intelligent waveform interception technology, which aims to solve the current technical problem that the stamping waveform interception of each stamping product is too complicated.

[0005] To achieve the above objectives, in a first aspect, the present application provides a stamping process monitoring method based on intelligent waveform interception technology, which specifically includes the following steps: The template stamping data is obtained by averaging the stamping data of multiple groups of normal products; The observation window is updated by sliding the monitored stamping data, and the stamping data whose distance to the template stamping data is a valley value is found in the observation window as the data of a single stamping; If the data of a single stamping exceeds the alarm range, the product of the single stamping is judged to be abnormal.

[0006] Preferably, after obtaining the template stamping data, verify whether the template stamping data is useful, specifically: Select the verification data including the stamping data; Setting a verification sliding window to traverse the verification data; Calculate the distance between the data in each verification sliding window and the template punching data; Find the valley distance from all distances. If the data in the verification sliding window corresponding to all valley distances is the stamping data in the verification data, it is determined that the verification has passed.

[0007] Preferably, the stamping data whose distance from the template stamping data is a valley value is found in the observation window as the data of a single stamping, specifically: Set the sliding window to traverse the stamping data within the observation window; Calculate the distance between the data in each sliding window and the template punching data; The valley distance is found from all distances, and the data in the sliding window corresponding to multiple consecutive valley distances are spliced, deduplicated and offset corrected to obtain the data of a single punching.

[0008] Preferably, the splicing and deduplication specifically includes: converting the data to be processed into curves, splicing the curves with the same parts together to obtain a complete curve; The offset correction is specifically: performing offset correction on the complete curve based on the curve range of the template punching data.

[0009] Preferably, the distance is Euclidean distance.

[0010] Preferably, the width of the observation window is greater than 1 times the width of the template punching data and less than 2 times the width of the template punching data.

[0011] Preferably, the width of the verification sliding window and the sliding window is equal to the width of the template stamping data.

[0012] Preferably, the alarm range is specifically: The template stamping data plus the preset tolerance value obtains the upper limit of the range; The template stamping data minus the preset tolerance value is the lower limit of the range; The upper range limit and the lower range limit are combined to obtain the alarm range.

[0013] Preferably, after finding the data of a single stamping, the maximum value is found therefrom, and the maximum value is converted into the stamping force of a single stamping based on the mapping relationship between strain and stress; each time a single stamping data is found, the number of stamping processes with load is accumulated once.

[0014] In a second aspect, the present application provides an electronic device comprising: at least one memory for storing programs; and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the first aspect or any possible implementation of the first aspect.

[0015] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the prior art: (1) This application uses the stamping data of normal products as template stamping data to intelligently intercept the continuously collected stamping data, obtain the data of each stamping, and further monitor the stamping process based on the single stamping data. This application solution does not require the addition of additional stamping counting equipment to the stamping equipment, thereby reducing the complexity and cost of the monitoring system.

[0016] (2) This application adds a tolerance to the normal stamping data to obtain an alarm envelope curve as the alarm range. By comparing the intercepted stamping data with the envelope curve, it is determined whether the stamping is normal. This judgment method has high computational efficiency and can monitor the stamping process in real time, screen out abnormal stamping, and avoid the manufacture of abnormal products.

[0017] (3) The monitoring method of the present application can also effectively monitor the number of loaded stamping processes and the stamping force of each stamping, thus enriching the monitoring data. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of a stamping process monitoring method based on intelligent waveform interception technology provided in an embodiment of the present application.

[0019] Figure 2 It is a waveform diagram of stamping data of 8 groups of normal products provided in the embodiment of the present application.

[0020] Figure 3 It is a schematic diagram of the process of offline verification of template stamping data provided in an embodiment of the present application.

[0021] Figure 4 It is a schematic diagram of the online data capture process of the current stamping provided in an embodiment of the present application.

[0022] Figure 5 It is a schematic diagram of the composition of the stamping process monitoring system provided in an embodiment of the present application.

[0023] Figure 6 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0025] The terms "first" and "second" in the specification and claims herein are used to distinguish different objects rather than to describe a specific order of the objects. For example, a first response message and a second response message are used to distinguish different response messages rather than to describe a specific order of the response messages.

[0026] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0027] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two. For example, multiple processing units refer to two or more processing units, etc.; multiple elements refer to two or more elements, etc.

[0028] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0029] Embodiment 1: like Figure 1 As shown, Example 1 of the present application specifically includes the following steps: (1) The template stamping data is obtained by averaging the stamping data of multiple groups of normal products.

[0030] (11) The stamping data during the stamping process is collected by installing strain sensors on the stamping equipment.

[0031] Strain sensors are installed at deformation-sensitive parts of stamping equipment, such as columns, beams and connecting rods. The strain sensors convert the deformation of the above parts into digital signals for collection.

[0032] (12) Align the stamping data of multiple groups of normal products on the time axis according to the peak position.

[0033] Record the stamping data of 8 normal products respectively, and then draw stamping curves respectively. Align the 8 sets of stamping curves according to the waveform of the stamping curves, such as Figure 2 As shown, it can be seen that the 8 groups of stamping curves basically overlap.

[0034] (13) The average value of each data collection point (each point on the horizontal axis) is taken as a set of template stamping data.

[0035] (14) After obtaining the template stamping data, verify the template stamping data, such as Figure 3 As shown, specifically: (141) Selecting verification data including stamping data; (142) Setting a verification sliding window to traverse the verification data, wherein the width of the verification sliding window is consistent with the width of the template stamping data; (143) Calculating the distance between the data in the verification sliding window and the template punching data; in this embodiment, the distance between the two sets of data is measured by the Euclidean distance; (144) All distances constitute a distance curve, all valley values ​​are found from the distance curve, and the verification sliding windows corresponding to all valley value distances are found. If the data in the verification sliding window is the stamping data in the verification data, it is determined that the verification is passed.

[0036] In this step, finding all valleys from the distance curve can also be changed to finding the peak after flipping the distance curve. For example: Calculate the distance between the data C in the verification sliding window and the template punching data N; Normalize all distances to the range [0,1]; Draw the distance curve and flip it; Perform peak detection to obtain the peak value; The data C in the verification sliding window corresponding to the peak distance is the data to be found.

[0037] (2) The template stamping data is expanded according to the preset tolerance to generate an alarm envelope curve, and the alarm envelope curve is the alarm range. The preset tolerance value can be set according to the required monitoring sensitivity. If a high sensitivity is required, the tolerance value is set smaller, otherwise the tolerance value is set larger.

[0038] (21) Add the preset tolerance value to the template stamping data to obtain the upper limit curve.

[0039] (22) Subtract the preset tolerance value from the template stamping data to obtain the lower limit curve.

[0040] (23) The alarm envelope curve is obtained by combining the upper limit curve and the lower limit curve. The stamping data between the alarm envelope curves is considered to be normal stamping.

[0041] (3) Use the monitored stamping data to slide and update the observation window, and find the stamping data with a valley value between the stamping data and the template in the observation window as the data for the current stamping.

[0042] like Figure 4 As shown, the specific steps include: (31) Use the monitored stamping data to slide and update the observation window. The width of the observation window should be greater than 1 times the width of the template stamping data and less than 2 times the width of the template stamping data.

[0043] (32) A sliding window is set to traverse the stamping data within the observation window; the width of the sliding window is equal to the width of the template stamping data.

[0044] (33) Calculate the distance between the data in the sliding window and the template punching data; in this embodiment, the distance between the two sets of data is measured by the Euclidean distance.

[0045] (34) Find the sliding window corresponding to the valley value distance, and perform deduplication and offset correction on the data in the sliding windows corresponding to multiple consecutive valley value distances to obtain the data of the current punching.

[0046] First, target splicing and deduplication are performed to merge duplicate targets into one target.

[0047] Then, according to the boundary of the template stamping data, the time series correction is performed on the deduplicated target to ensure that the target and the template stamping data are aligned on the time axis.

[0048] (35) After finding the data of the current stamping, find the maximum value of the data, and convert the maximum value of the data into the stamping pressure of the current stamping based on the mapping relationship between strain and stress.

[0049] The mapping relationship between strain and stress is established by applying force on the stamping equipment with a loader before stamping production, marking the strain values ​​under different load forces, and establishing the mapping relationship between strain and stamping force.

[0050] (36) Every time a stamping data is found, the number of stamping processes with load is accumulated.

[0051] In this step, the distance curve may be flipped and then peak detection may be performed instead of directly searching for valley values ​​from the distance curve.

[0052] (4) If the data of the current stamping exceeds the range of the alarm envelope curve, it is determined that the product of the current stamping is abnormal.

[0053] Embodiment 2: like Figure 5 As shown, it is a schematic diagram of the corresponding system composition for executing the method of the present application, which specifically includes the following parts: acquisition terminal 1, acquisition terminal 2, acquisition terminal 3, acquisition terminal 4, external power supply, switching power supply, data conversion module, local server and remote service center.

[0054] The stress sensors in the collection terminals 1, 2, 3 and 4 are respectively installed at different stress-sensitive parts of the stamping equipment, such as connecting rods, columns and measuring parts, etc. The stamping strain data is collected during the operation of the stamping equipment.

[0055] The external power supply is used to power the acquisition end after voltage conversion through the adapter power supply.

[0056] The stamping strain data collected by the acquisition end enters the local server after passing through the data conversion module. The local server uploads the strain data to the remote service center at the other end of the network. The remote service center performs intelligent waveform interception on the collected stamping stress data, obtains the stamping data of each stamping process, and then makes stamping anomaly judgment based on the intercepted stamping data.

[0057] It is understandable that the detailed functional implementation of the above-mentioned remote service center can be found in the introduction of the aforementioned method embodiment, and will not be elaborated here.

[0058] Based on the method in the above embodiment, the embodiment of the present application provides an electronic device that may include: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus. The processor may call the logic instructions in the memory to execute the method in the above embodiment.

[0059] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application.

[0060] Based on the method in the above embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method in the above embodiment.

[0061] Based on the method in the above embodiment, an embodiment of the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method in the above embodiment.

[0062] It is understandable that the processor in the embodiment of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0063] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC.

[0064] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted through the computer-readable storage medium. The computer instructions may be transmitted from a website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

[0065] It should be understood that the various numerical numbers involved in the embodiments of the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application.

[0066] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A stamping process monitoring method based on intelligent waveform interception technology, characterized in that: The specific steps include: The template stamping data is obtained by averaging the stamping data of multiple groups of normal products; The observation window is updated by sliding the monitored stamping data, and the stamping data whose distance to the template stamping data is a valley value is found in the observation window as the data of a single stamping; If the data of a single stamping exceeds the alarm range, the product of the single stamping is judged to be abnormal.

2. The stamping process monitoring method according to claim 1, characterized in that: After obtaining the template stamping data, verify whether the template stamping data is useful, specifically: Select the verification data including the stamping data; Setting a verification sliding window to traverse the verification data; Calculate the distance between the data in each verification sliding window and the template punching data; Find the valley distance from all distances. If the data in the verification sliding window corresponding to all valley distances is the stamping data in the verification data, it is determined that the verification has passed.

3. The stamping process monitoring method according to claim 1, characterized in that: Find the stamping data with a valley value between the stamping data of the template in the observation window as the data of a single stamping, specifically: Set the sliding window to traverse the stamping data within the observation window; Calculate the distance between the data in each sliding window and the template punching data; The valley distance is found from all distances, and the data in the sliding window corresponding to multiple consecutive valley distances are spliced, deduplicated and offset corrected to obtain the data of a single punching.

4. The stamping process monitoring method according to claim 3, characterized in that: The splicing and deduplication specifically includes: converting the data to be processed into curves, splicing the curves with the same parts together to obtain a complete curve; The offset correction is specifically: performing offset correction on the complete curve based on the curve range of the template punching data.

5. The stamping process monitoring method according to claim 1, 2 or 3, characterized in that: The distance is the Euclidean distance.

6. The stamping process monitoring method according to claim 1 or 3, characterized in that: The width of the observation window is greater than 1 times the width of the template punching data and less than 2 times the width of the template punching data.

7. The stamping process monitoring method according to claim 2 or 3, characterized in that: The width of the verification sliding window and the sliding window is equal to the width of the template punching data.

8. The stamping process monitoring method according to claim 1, characterized in that: The alarm range is specifically: The template stamping data plus the preset tolerance value obtains the upper limit of the range; The template stamping data minus the preset tolerance value is the lower limit of the range; The upper range limit and the lower range limit are combined to obtain the alarm range.

9. The stamping process monitoring method according to claim 1, characterized in that: After finding the data of a single stamping, find the maximum value therefrom, and convert the maximum value into the stamping force of a single stamping based on the mapping relationship between strain and stress; each time a single stamping data is found, the number of stamping processes with load is accumulated once.

10. An electronic device, characterized in that: include: at least one memory for storing a computer program; At least one processor is used to execute the program stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method according to any one of claims 1 to 9.

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