Online monitoring method and module for numerical control engraving and milling system

Abstract

The application discloses a numerical control engraving and milling system online monitoring method and module, comprising the following steps: S1, an AI system acquires a projection center; S2, a reference is established; S3, visual detection; S4, position judgment and tool feeding processing; S5, correction of the theoretical projection center; S6, adjustment of the tool feeding amount. The initial projection center of a workpiece is used as a reference to establish a three-dimensional coordinate system, and the three-dimensional coordinate system coordinate reference is used as the theoretical projection center of the workpiece; the actual projection center position of the workpiece is acquired after visual detection of one-time processing; whether the workpiece has displacement is judged by comparing whether the actual projection center of the workpiece and the theoretical projection center overlap; the theoretical projection center is corrected to the actual projection center when the workpiece moves, and the workpiece is processed by taking the position as a reference; the position information of the workpiece is corrected instead of the actual position, and the workpiece does not need to be adjusted by using an adjusting component.

Description

Technical Field

[0001] This invention belongs to the field of intelligent workpiece processing technology, and particularly relates to an online monitoring method for CNC engraving and milling systems. Background Technology

[0002] A CNC engraving and milling machine is a high-precision, multi-functional CNC equipment mainly used for precision engraving and milling of various materials. It combines the features of engraving and milling machines and milling machines, possessing high-speed and high-precision processing capabilities, and is widely used in mold manufacturing, handicraft processing, electronic component manufacturing, and other fields.

[0003] When milling, the movement of the tool may cause the workpiece to move, resulting in the actual amount of workpiece being processed being less than the given amount. When using a robot or other adjustment components to adjust the workpiece, if the workpiece has high machining accuracy, the adjustment components may not be able to adjust the workpiece accurately or the adjustment process may be very complex, thus affecting the machining speed and efficiency of the workpiece. Summary of the Invention

[0004] This invention addresses the problem in existing technologies where adjustment components cannot accurately adjust the workpiece moving due to tool movement, thus affecting the workpiece's processing speed. The following technical solution is proposed:

[0005] The online monitoring method for CNC engraving and milling systems includes the following steps:

[0006] S1, AI system obtains projection center;

[0007] After the workpiece is clamped and fixed, the AI ​​system's camera acquires an image of the workpiece to determine the initial projection of the finished workpiece on the bottom surface of the workpiece.

[0008] S2. Establish a benchmark;

[0009] A three-dimensional coordinate system is established with the initial projection center as the reference, and the coordinate reference of this three-dimensional coordinate system is used as the theoretical projection center of the workpiece.

[0010] S3, Visual Inspection;

[0011] The initial cutting process is performed, followed by online monitoring of the actual projection center position of the workpiece by the AI ​​system's camera.

[0012] S4. Position determination and tool feeding;

[0013] Determine whether the actual projection center of the machined part overlaps with the theoretical projection center:

[0014] If there is overlap and the workpiece has not been displaced, determine whether to continue tool feeding. If tool feeding is required, perform a single tool feeding operation and repeat step S3.

[0015] If there is no overlap, the workpiece will be displaced, and the process will proceed directly to step S5.

[0016] S5, Correction Theory Projection Center;

[0017] Correct the theoretical projection center to make it coincide with the actual projection center of the workpiece, and proceed to step S6.

[0018] S6. Adjust the feed rate;

[0019] Adjust the single feed rate to control the machining amount. After machining is completed, proceed to step S3.

[0020] As a preferred embodiment of the above technical solution, step S6 includes the following:

[0021] S6.1 The AI ​​system uses a camera to measure the distance between the theoretical projection center and the actual projection center to obtain the processing quantity;

[0022] S6.2 Calculate the number of feeds based on the machining quantity;

[0023] S6.3, Set the number of feeds to control the amount of feed per single tool operation.

[0024] As a preferred embodiment of the above technical solution, the machining amount is L, the tool feed amount is d, the number of tool feeds is n, and the relationship between the machining amount L, the tool feed amount d, and the number of tool feeds n is L = n × d. Steps S3 and S4 are repeated after each tool feed.

[0025] As a preferred embodiment of the above technical solution, step S4 further includes the following steps: if the actual projection center of the workpiece overlaps with the theoretical projection center and the workpiece has not been displaced, determine whether subsequent tool feeding is required; if no tool feeding is required, then the machining is completed.

[0026] As a preferred embodiment of the above technical solution, the following steps are also included:

[0027] S7. Processing completed;

[0028] The workpiece is processed for the last time, and the actual projection center of the workpiece overlaps with the theoretical projection center. The workpiece is then removed to complete the engraving and milling work.

[0029] As a preferred embodiment of the above technical solution, the initial projection center located at the position of the workpiece and the actual projection center located at the position of the workpiece are based on the same reference.

[0030] As a preferred embodiment of the above technical solution, S2 further includes setting an initial projection center, with the AI ​​system's camera acquiring an image of the workpiece to be processed and marking the initial projection center on the bottom of the workpiece.

[0031] As a preferred embodiment of the above technical solution, S3 further includes determining the actual projection center of the workpiece. The camera of the AI ​​system acquires the bottom image of the workpiece after each processing. If the bottom image of the workpiece changes, the actual projection center position is determined based on the image comparison.

[0032] As a preferred embodiment of the above technical solution, the AI ​​system has multiple cameras, which are located at the bottom and one side of the workpiece, respectively.

[0033] The online monitoring module of the CNC engraving and milling system includes: an image detection and recognition module, a spatial reference module, an intelligent judgment module, and a central control module. The image detection and recognition module is used to acquire images of the workpiece in steps S1 and S3. The spatial reference module is used to create and store three-dimensional coordinate systems in steps S2, S4, and S6 to mark the initial projection center, the actual projection center, and the theoretical projection center. The intelligent judgment module is used to determine the positions of the theoretical projection center and the actual projection center in steps S4 and S6 and calculate and adjust the tool feed. The central control module is used to provide signals for the transition between each step.

[0034] The beneficial effects of this invention are as follows:

[0035] 1. The CNC engraving and milling system of the present invention directly eliminates the need for the actuator to perform position correction, thus eliminating the need for secondary positioning. It directly performs reference offset and correction, that is, directly enters step S5, thereby achieving real-time monitoring and ensuring machining accuracy.

[0036] 2. Establish a three-dimensional coordinate system based on the initial projection center of the workpiece, and use this three-dimensional coordinate system as the theoretical projection center of the workpiece. After one processing cycle, visual inspection obtains the actual projection center position of the workpiece. By comparing whether the actual projection center of the workpiece overlaps with the theoretical projection center, it is determined whether the workpiece has been displaced. When the workpiece moves, the theoretical projection center is corrected to the actual projection center, and this point is used as the reference for processing the workpiece. By correcting the position information of the workpiece instead of its actual position, there is no need to use adjustment components to adjust the workpiece, thereby ensuring the processing speed and efficiency of the workpiece.

[0037] 3. After obtaining the distance between the theoretical projection center and the actual projection center and the machining amount, calculate the number of tool feeds. By setting different number of tool feeds, control the required machining amount, thereby accurately machining the workpiece and making up for the machining amount lost due to the movement of the workpiece.

[0038] 4. By using visual inspection to compare the bottom image of the workpiece after each processing, the actual projection center position can be determined when the bottom image of the workpiece changes (i.e., the bottom part of the workpiece is cut), thereby ensuring the comparison and judgment of the actual projection center of the workpiece with the theoretical projection center. Attached Figure Description

[0039] Figure 1 The diagram shows a flowchart of an online monitoring method for a CNC milling system according to an embodiment. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments and the accompanying drawings.

[0041] Example

[0042] The online monitoring method for CNC engraving and milling systems includes the following steps:

[0043] S1, AI system obtains projection center;

[0044] After the workpiece is clamped and fixed, the AI ​​system's camera acquires an image of the workpiece to determine the initial projection of the finished workpiece on the bottom surface of the workpiece.

[0045] S2. Establish a benchmark;

[0046] A three-dimensional coordinate system is established with the initial projection center as the reference, and the coordinate reference of this three-dimensional coordinate system is used as the theoretical projection center of the workpiece.

[0047] S3, Visual Inspection;

[0048] The initial cutting process is performed, followed by online monitoring of the actual projection center position of the workpiece by the AI ​​system's camera.

[0049] S4. Position determination and tool feeding;

[0050] Determine whether the actual projection center of the machined part overlaps with the theoretical projection center:

[0051] If there is overlap and the workpiece has not been displaced, determine whether to continue tool feeding. If tool feeding is required, perform a single tool feeding operation and repeat step S3.

[0052] If there is no overlap, the workpiece will be displaced, and the process will proceed directly to step S5.

[0053] S5, Correction Theory Projection Center;

[0054] Correct the theoretical projection center to make it coincide with the actual projection center of the workpiece, and proceed to step S6.

[0055] S6. Adjust the feed rate;

[0056] Adjust the single feed rate to control the machining amount. After machining is completed, proceed to step S3.

[0057] The S4 step also includes the following steps: if the actual projection center of the workpiece overlaps with the theoretical projection center and the workpiece has not been displaced, determine whether to perform subsequent tool feeding; if no tool feeding is required, then the processing is completed.

[0058] A three-dimensional coordinate system is established with the initial projection center of the workpiece as the reference, and this three-dimensional coordinate system is used as the theoretical projection center of the workpiece. After one processing cycle, visual inspection obtains the actual projection center position of the workpiece. By comparing whether the actual projection center of the workpiece overlaps with the theoretical projection center, it is determined whether the workpiece has been displaced. When the workpiece moves, the theoretical projection center is corrected to the actual projection center, and this point is used as the reference for processing the workpiece. By correcting the position information of the workpiece rather than its actual position, there is no need to use adjustment components to adjust the workpiece, thereby ensuring the processing speed and efficiency of the workpiece.

[0059] Step S6 includes the following:

[0060] S6.1 The AI ​​system uses a camera to measure the distance between the theoretical projection center and the actual projection center to obtain the processing quantity;

[0061] S6.2 Calculate the number of feeds based on the machining quantity;

[0062] S6.3, Set the number of feeds to control the amount of feed per single tool operation.

[0063] The processing amount is L, the tool feed amount is d, and the number of tool feeds is n. The relationship between the processing amount L, the tool feed amount d, and the number of tool feeds n is L = n × d. Steps S3 and S4 are repeated after each tool feed.

[0064] After obtaining the machining amount by measuring the distance between the theoretical projection center and the actual projection center, the number of tool feeds is calculated. By setting different number of tool feeds, the required machining amount is controlled, thereby accurately machining the workpiece and making up for the machining amount lost due to the movement of the workpiece.

[0065] The CNC engraving and milling system of the present invention has the following disadvantages if the existing actuator is used to correct the position of the workpiece after a single machining operation, i.e., in step S4:

[0066] 1. A separate actuator, such as a robotic arm, needs to be added.

[0067] 2. The corrected workpiece needs to be repositioned; otherwise, subsequent processing cannot be carried out. For example, if the offset is 3mm, the actual offset may be 3.1mm due to differences in inertia, friction, etc., thus making precise processing impossible.

[0068] 3. Regardless of whether there is an actuator, such as a robotic arm, the workpiece to be processed after correction must undergo secondary visual positioning.

[0069] Therefore, the CNC engraving and milling system of the present invention directly eliminates the need for the actuator to perform position correction, thus eliminating the need for secondary positioning. It directly performs reference offset and correction, that is, directly enters step S5, thereby achieving real-time monitoring and ensuring machining accuracy.

[0070] It also includes the following steps:

[0071] S7. Processing completed;

[0072] The workpiece is processed for the last time, and the actual projection center of the workpiece overlaps with the theoretical projection center. The workpiece is then removed to complete the engraving and milling work.

[0073] The initial projection center at the location of the workpiece and the actual projection center at the location of the workpiece are based on the same reference.

[0074] The S2 also includes setting an initial projection center, with the AI ​​system's camera acquiring an image of the workpiece and marking the initial projection center on the bottom of the workpiece.

[0075] S3 also includes determining the actual projection center of the workpiece. The camera of the AI ​​system acquires the bottom image of the workpiece after each processing. If the bottom image of the workpiece changes, the actual projection center position is determined based on the image comparison.

[0076] By comparing the bottom images of the workpiece after each processing using visual inspection, the actual projection center position can be determined when the bottom image of the workpiece changes (i.e., the bottom part of the workpiece is cut), thus ensuring the comparison and judgment between the actual projection center and the theoretical projection center of the workpiece.

[0077] The AI ​​system has multiple cameras, which are located on the bottom and one side of the workpiece, respectively.

[0078] The online monitoring module of the CNC engraving and milling system includes: an image detection and recognition module, a spatial reference module, an intelligent judgment module, and a central control module. The image detection and recognition module is used to acquire images of the workpiece in steps S1 and S3. The spatial reference module is used to create and store three-dimensional coordinate systems in steps S2, S4, and S6 to mark the initial projection center, the actual projection center, and the theoretical projection center. The intelligent judgment module is used to determine the positions of the theoretical projection center and the actual projection center in steps S4 and S6 and calculate and adjust the tool feed. The central control module is used to provide signals for the transition between each step.

[0079] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it.

Claims

1. An online monitoring method for CNC engraving and milling systems, characterized in that, Includes the following steps: S1, AI system obtains projection center; After the workpiece is clamped and fixed, the AI ​​system's camera acquires an image of the workpiece to determine the initial projection of the finished workpiece on the bottom surface of the workpiece. S2. Establish a benchmark; A three-dimensional coordinate system is established with the initial projection center as the reference, and the coordinate reference of this three-dimensional coordinate system is used as the theoretical projection center of the workpiece. S3, Visual Inspection; The initial cutting process is performed, followed by online monitoring of the actual projection center position of the workpiece by the AI ​​system's camera. S4. Position determination and tool feeding; Determine whether the actual projection center of the machined part overlaps with the theoretical projection center: If there is overlap and the workpiece has not been displaced, determine whether to continue tool feeding. If tool feeding is required, perform a single tool feeding operation and repeat step S3. If there is no overlap, the workpiece will be displaced, and the process will proceed directly to step S5. S5, Correction Theory Projection Center; Correct the theoretical projection center to make it coincide with the actual projection center of the workpiece, and proceed to step S6. S6. Adjust the feed rate; Adjust the single feed rate to control the machining amount. After machining is completed, proceed to step S3.

2. The online monitoring method for a CNC engraving and milling system according to claim 1, characterized in that, Step S6 includes the following: S6.1 The AI ​​system uses a camera to measure the distance between the theoretical projection center and the actual projection center to obtain the processing quantity; S6.2 Calculate the number of feeds based on the machining quantity; S6.3, Set the number of feeds to control the amount of feed per single tool operation.

3. The online monitoring method for a CNC engraving and milling system according to claim 2, characterized in that, The machining quantity is L, the tool feed rate is d, and the number of tool feeds is n. The relationship between the machining quantity L, the tool feed rate d, and the number of tool feeds n is as follows: Repeat steps S3 and S4 after each cutting.

4. The online monitoring method for a CNC engraving and milling system according to claim 1, characterized in that, The S4 step also includes the following steps: if the actual projection center of the workpiece overlaps with the theoretical projection center and the workpiece has not been displaced, determine whether to perform subsequent tool feeding; if no tool feeding is required, then the machining is completed.

5. The online monitoring method for a CNC engraving and milling system according to claim 1, characterized in that, It also includes the following steps: S7. Processing completed; The workpiece is processed for the last time, and the actual projection center of the workpiece overlaps with the theoretical projection center. The workpiece is then removed to complete the engraving and milling work.

6. The online monitoring method for a CNC engraving and milling system according to claim 1, characterized in that, The initial projection center at the location of the workpiece and the actual projection center at the location of the workpiece are based on the same reference.

7. The online monitoring method for a CNC engraving and milling system according to claim 1, characterized in that, The S2 also includes setting an initial projection center, with the AI ​​system's camera acquiring an image of the workpiece and marking the initial projection center on the bottom of the workpiece.

8. The online monitoring method for a CNC engraving and milling system according to claim 1, characterized in that, S3 also includes determining the actual projection center of the workpiece. The AI ​​system's camera acquires the bottom image of the workpiece after each processing. If the bottom image of the workpiece changes, the actual projection center position is determined based on the image comparison.

9. The online monitoring method for a CNC engraving and milling system according to claim 2, characterized in that, The AI ​​system has multiple cameras, which are located on the bottom and one side of the workpiece, respectively.

10. An online monitoring module for a CNC engraving and milling system, wherein the online monitoring module for a CNC engraving and milling system executes the online monitoring method for a CNC engraving and milling system according to any one of claims 1-9, characterized in that, include: The system comprises an image detection and recognition module, a spatial reference module, an intelligent judgment module, and a central control module. The image detection and recognition module acquires images of the workpiece in steps S1 and S3. The spatial reference module creates and stores a three-dimensional coordinate system in steps S2, S4, and S6 to mark the initial projection center, the actual projection center, and the theoretical projection center. The intelligent judgment module determines the positions of the theoretical projection center and the actual projection center in steps S4 and S6 and calculates and adjusts the tool feed. The central control module provides signals for the transitions between steps.

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