A method and system for automatically generating a part machining process using a three-dimensional model

Abstract

This invention relates to the field of data processing technology, and in particular to a method and system for automatically generating machining processes for parts using 3D models. The method includes: acquiring a 3D model to be cut; acquiring several simple structural 3D models; classifying these models into several sets; responding to the existence of a first model set, proceeding to the next step; if no model set exists, proceeding directly to the next step; calculating the tool head movement score, selecting the simple structural 3D model with the lowest tool head movement score as the next tool entry position, repeating this step until a first cutting path corresponding to the first model set is generated; acquiring a third cutting 3D model, calculating the external proportion, determining the generation order of the paths corresponding to each model set based on the external proportion, and sequentially generating the cutting paths corresponding to each model set; and generating the machining process. This invention can reduce the time wasted due to frequent tool head and tool head angle switching, shorten machining time, and increase machining efficiency.

Description

Technical Field

[0001] This application relates to the field of data processing technology, and more specifically, to a method and system for automatically generating part machining processes using a three-dimensional model. Background Technology

[0002] With the continuous development of technology, the structure of parts is becoming more and more complex. The processing technology of parts has gradually developed from the original method of programmers relying on manual experience to manually divide the processing area, arrange the processing sequence and processing route to the field of intelligence and digitalization. 3D model-driven digital manufacturing technology has become the mainstream development direction of high-end equipment parts manufacturing.

[0003] Current 3D model-based part machining processes have achieved a certain degree of automation, but limitations still exist. On the one hand, existing machining sequences largely rely on geometric topological relationships and human experience, lacking a unified quantification of actual machining conditions such as the time cost of tool head type and angle switching, tool head movement time cost, and structural accessibility. This results in long tool head idle strokes, frequent angle switching, and wasted time. On the other hand, the surface exposure degree of the part is not considered during machining, which can easily lead to situations such as inside-to-outside or shallow-to-deep machining, posing a high risk of interference.

[0004] Therefore, the existing technology has defects and urgently needs improvement. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for automatically generating part machining processes using a three-dimensional model. This addresses the following issues in the existing technology: First, existing machining sequences often rely on geometric topological relationships and manual experience, lacking a unified quantification of actual machining conditions such as the time cost of tool head type and angle switching, tool head movement time cost, and structural accessibility. This results in long tool head idle strokes, frequent angle switching, and wasted time. Second, the surface exposure degree of the part is not considered during machining, which can easily lead to situations such as inside-to-outside or shallow-to-deep machining, posing a high risk of interference.

[0006] This invention provides a method for automatically generating part machining processes using a three-dimensional model, comprising: Step S1: Obtain the 3D model of the finished part and the 3D model of the blank. Combine the Boolean difference set operation to obtain the 3D model of the blank that needs to be cut off during the part processing. Step S2: Obtain the reference structure during the part machining process and determine the first cutting three-dimensional model. Determine the second cutting three-dimensional model based on the three-dimensional model to be cut and the first cutting three-dimensional model. Decompose the second cutting three-dimensional model according to the preset splitting rules to form several simple structure three-dimensional models. Step S3: Classify the three-dimensional models of each simple structure according to the type of the cutting head corresponding to each simple structure three-dimensional model to obtain several model sets. If there is a first model set with the same cutting head type as the reference structure, execute step S4. If not, directly execute step S5. Step S4: For the first set of models with the same tool head type and reference structure, obtain the infeed angle between the infeed direction and the initial infeed direction of each simple structure 3D model, as well as the infeed position coordinates of each simple structure 3D model. Calculate the tool head movement score based on the infeed angle and infeed position of each simple structure 3D model, select the simple structure 3D model with the lowest tool head movement score as the next infeed position, and repeat this step until the first cutting path corresponding to the first set of models is generated. Step S5: Obtain the third cutting 3D model after the first model set has been processed. Calculate the external proportion of each model set in the third cutting 3D model. Determine the generation order of the corresponding routes for each model set according to the external proportion from high to low. For a single model set, select the entry position of the simple structure 3D model that is closest to the tool change position as the initial entry position. Calculate the tool head movement score based on the entry angle and entry position of each simple structure 3D model. Select the simple structure 3D model with the lowest tool head movement score as the next entry position until the cutting route corresponding to a single model set is generated. Repeat this step according to the generation order to obtain the cutting routes corresponding to all model sets. Step S6: Generate machining process based on the cutting paths corresponding to all model sets; The reference structure is a geometric feature that can provide a reference for subsequent machining positioning.

[0007] As a preferred technical solution for an automatic generation method of part machining process using a three-dimensional model, the process involves obtaining the reference structure in the part machining process and mapping it to the three-dimensional model to be cut, determining the first three-dimensional model for cutting, determining the second three-dimensional model for cutting based on the three-dimensional model to be cut and the first three-dimensional model for cutting, mapping the reference structure to the three-dimensional model to be cut, obtaining the three-dimensional model of the blank that needs to be cut off during the machining of the reference structure, using Boolean difference set operation to remove the three-dimensional model of the blank that needs to be cut off during the machining of the reference structure from the three-dimensional model to be cut, and recording the three-dimensional model obtained after removal as the second three-dimensional model for cutting.

[0008] As a preferred technical solution for an automatic generation method of part processing technology using 3D models, the preset splitting rules are configured with several basic 3D models. Each basic 3D model is a single geometric body and cannot be further split into a combination of single geometric bodies of other basic 3D models. During the splitting process, the following conditions must also be met: The area of ​​each simple structural 3D model after decomposition on the outer surface of the second cutting 3D model accounts for more than or equal to 5% of the surface area of ​​the second cutting 3D model; The angle between each of the decomposed simple structure 3D models and other simple structure 3D models is less than or equal to 30°.

[0009] As a preferred technical solution for an automatic part machining process generation method utilizing 3D models, the method obtains the infeed angle between the infeed direction and the initial infeed direction of each simple structural 3D model, as well as the infeed position coordinates of each simple structural 3D model, including: Obtain the feed direction and initial feed direction of each simple structure 3D model, establish a feed vector and an initial feed vector with a length of unit length and directions of feed direction, respectively, calculate the angle between the feed vector and the initial feed vector and record it as the transformation angle; The coordinates of the point on each simple structure 3D model that is closest to the reference structure after machining are obtained are used as the tool entry position coordinates of each simple structure 3D model.

[0010] As a preferred technical solution for an automatic part machining process generation method utilizing 3D models, the calculation of the tool head movement score based on the infeed angle and infeed position of each simple structural 3D model includes: Obtain the transformation angle and the tool entry position coordinates of each simple structural 3D model; The distance between the point coordinates of the tool head coordinates after the machining of the reference structure is completed and the tool entry position coordinates of each simple structure 3D model is recorded as the tool head displacement distance. Assign corresponding weight coefficients to the conversion angle and the cutter head displacement distance respectively, calculate the sum of the products of the conversion angle and the cutter head displacement distance and the corresponding weight coefficients, and record it as the cutter head movement score.

[0011] As a preferred technical solution for an automatic generation method of part machining processes using three-dimensional models, the calculation of the external proportion of each model set in the third cutting three-dimensional model includes: For a single model set, the area of ​​the surface of each simple structure 3D model in the model set on the outer surface of the third cutting 3D model is obtained and recorded as the exposed area. The ratio of the exposed area to the outer surface area of ​​the third cutting 3D model is recorded as the external proportion.

[0012] As a preferred technical solution for an automatic part machining process generation method utilizing 3D models, the machining process is generated based on the cutting paths corresponding to the set of all simple structural 3D models, and also includes the generation of cutting paths for the reference structure, including: The point on the reference structure closest to the initial position of the tool head before machining the part is selected as the infeed position of the reference structure, and the cutting path of the reference structure is generated by using a helical infeed method.

[0013] As a preferred technical solution for automatically generating part machining processes using 3D models, after obtaining the 3D model of the finished part and the 3D model of the blank, a model preprocessing process is also included, including: The coordinates of the finished part 3D model and the blank 3D model are aligned. The bottom surface, internal center line or external edge line of the blank 3D model are used as positioning references to construct a 3D coordinate system and project the finished part 3D model into the 3D coordinate system. Leave a machining allowance of 0.5 to 5 mm on the surface of the part before performing the Boolean difference operation.

[0014] This invention also provides an automatic part machining process generation system utilizing a three-dimensional model, comprising: The model building unit obtains the 3D model of the finished part and the 3D model of the blank, and combines Boolean difference set operation to obtain the 3D model of the part of the blank that needs to be cut off during the part processing. The model splitting unit obtains the reference structure during the part processing and determines the first cutting three-dimensional model. Based on the three-dimensional model to be cut and the first cutting three-dimensional model, it determines the second cutting three-dimensional model. According to the preset splitting rules, the second cutting three-dimensional model is split to form several simple structure three-dimensional models. The determination unit classifies the three-dimensional models of each simple structure according to the type of the cutting head corresponding to each simple structure three-dimensional model to obtain several model sets. In response to the existence of a first model set with the same cutting head type as the reference structure, the first operation unit is run. If no such set exists, the second operation unit is run directly. The first processing unit, for the first model set with the same tool head type and reference structure, obtains the infeed angle between the infeed direction and the initial infeed direction of each simple structure 3D model, as well as the infeed position coordinates of each simple structure 3D model. Based on the infeed angle and infeed position of each simple structure 3D model, it calculates the tool head movement score, selects the simple structure 3D model with the lowest tool head movement score as the next infeed position, and repeats this step until the first cutting path corresponding to the first model set is generated; The second processing unit obtains the third cutting 3D model after the first model set has been processed, calculates the external proportion of each model set in the third cutting 3D model, determines the generation order of the corresponding routes for each model set according to the external proportion from high to low, selects the infeed position of the simple structure 3D model closest to the tool change position as the initial infeed position for a single model set, calculates the tool head movement score based on the infeed angle and infeed position of each simple structure 3D model, selects the simple structure 3D model with the lowest tool head movement score as the next infeed position, until the cutting route corresponding to a single model set is generated, and repeats this step according to the generation order to obtain the cutting routes corresponding to all model sets; The output unit generates a machining process based on the cutting paths corresponding to all the model sets.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention obtains the three-dimensional model of the part and the three-dimensional model of the blank, places the three-dimensional model of the part and the three-dimensional model of the blank together by coordinate alignment, and obtains the three-dimensional model of the part of the blank that needs to be cut off by combining Boolean difference set operation. On this basis, a reference structure that must be processed first is introduced. This part cannot be sorted in terms of processing order. This part is removed to obtain the second cutting three-dimensional model. The second cutting three-dimensional model is divided into several simple structures by preset rules. Each simple structure has its own infeed direction and corresponding processing head. The simple structures are classified by the type of the cutting head. For simple structures with the same type of cutting head, the cutting head movement score is calculated by the infeed angle and the infeed position. The optimal solution of the next simple structure to be processed at the current cutting head position can be obtained, which reduces the time wasted due to frequent switching of cutting head and cutting head angle, shortens the processing time, and increases the processing efficiency. Attached Figure Description

[0016] Figure 1 The flowchart illustrates the steps of an automatic part machining process generation method using a three-dimensional model provided by the present invention. Figure 2 The diagram shows a structural block diagram of an automatic part machining process generation system based on a three-dimensional model provided by the present invention. Detailed Implementation

[0017] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0018] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0019] like Figure 1 As shown, this invention discloses a method for automatically generating part machining processes using a three-dimensional model, comprising: Step S1: Obtain the 3D model of the finished part and the 3D model of the blank. Combine the Boolean difference set operation to obtain the 3D model of the blank that needs to be cut off during the part processing. Step S2: Obtain the reference structure during the part machining process and determine the first cutting three-dimensional model. Determine the second cutting three-dimensional model based on the three-dimensional model to be cut and the first cutting three-dimensional model. Decompose the second cutting three-dimensional model according to the preset splitting rules to form several simple structural three-dimensional models. Step S3: Classify the three-dimensional models of each simple structure according to the type of the cutting head corresponding to each simple structure three-dimensional model to obtain several model sets. If there is a first model set with the same cutting head type as the reference structure, execute step S4. If not, directly execute step S5. Step S4: For the first set of models with the same tool head type and reference structure, obtain the infeed angle between the infeed direction and the initial infeed direction of each simple structure 3D model, as well as the infeed position coordinates of each simple structure 3D model. Calculate the tool head movement score based on the infeed angle and infeed position of each simple structure 3D model, select the simple structure 3D model with the lowest tool head movement score as the next infeed position, and repeat this step until the first cutting path corresponding to the first set of models is generated. Step S5: Obtain the third cutting 3D model after the first model set has been processed. Calculate the external proportion of each model set in the third cutting 3D model. Determine the generation order of the corresponding routes for each model set according to the external proportion from high to low. For a single model set, select the entry position of the simple structure 3D model that is closest to the tool change position as the initial entry position. Calculate the tool head movement score based on the entry angle and entry position of each simple structure 3D model. Select the simple structure 3D model with the lowest tool head movement score as the next entry position until the cutting route corresponding to a single model set is generated. Repeat this step according to the generation order to obtain the cutting routes corresponding to all model sets. Step S6: Generate the machining process based on the cutting paths corresponding to all model sets; The reference structure is a geometric feature that can provide a reference for subsequent machining positioning.

[0020] It should be noted that, in this embodiment of the invention, the reference structure includes, but is not limited to, a positioning plane, a reference hole, and a central axis. The cutter types include, but are not limited to, flat end mills, ball end mills, nose end mills, drills, reamers, and chamfering tools. The first cutting 3D model is a 3D model marked with the blank structure cut off during the machining of the reference structure; the second cutting 3D model is the remaining 3D model obtained by removing the 3D model marked with the blank structure cut off during the machining of the reference structure from the first cutting 3D model using Boolean difference operations. Simple structure 3D models include, but are not limited to, cubes, cuboids, cylinders, spheres, cones, or conical prisms. Each simple structure 3D model can be independently machined and cannot be further divided into combinations of other basic 3D geometric shapes. The second cutting 3D model can be divided according to preset division rules based on a CAD or CAM platform. This process simply decomposes a complex 3D model into several simple 3D structures, and will not be elaborated further here.

[0021] In detail, this invention obtains a 3D model of the part and a 3D model of the blank, places the 3D models of the part and the blank together, and obtains a 3D model of the part of the blank that needs to be cut off through Boolean difference operation. Based on this, a reference structure that must be processed first is introduced. This part cannot be sorted in terms of processing order, so this part is removed to obtain a second cutting 3D model. The second cutting 3D model is divided into several simple structures according to preset rules. Each simple structure has its own infeed direction and corresponding processing head. Simple structures are classified by the type of cutting head. For simple structures with the same type of cutting head, the cutting head movement score is calculated by the infeed angle and the infeed position. This can obtain the optimal solution for the next simple structure to be processed at the current cutting head position (switching the cutting head position and cutting head angle will cause time waste. Based on this idea, a method for calculating the cutting head movement score is constructed. The lower the cutting head movement score, the less time waste caused by switching the cutting head position and cutting head angle will be). This reduces the time waste caused by frequent switching of cutting head and cutting head angle, shortens the processing time, and increases processing efficiency.

[0022] Furthermore, the reference structure during the part machining process is obtained and mapped to the three-dimensional model to be cut, and the first three-dimensional model for cutting is determined. The second three-dimensional model for cutting is determined based on the three-dimensional model to be cut and the first three-dimensional model for cutting. The reference structure is mapped to the three-dimensional model to be cut, and the three-dimensional model of the blank that needs to be cut off during the machining of the reference structure is obtained. Boolean difference set operation is used to remove the three-dimensional model of the blank that needs to be cut off during the machining of the reference structure from the three-dimensional model to be cut, and the three-dimensional model obtained after removal is recorded as the second three-dimensional model for cutting.

[0023] In detail, through Boolean difference operations, the three-dimensional model that needs to be cut off during the machining of the reference structure is subtracted from the three-dimensional model that needs to be cut off during the overall part machining process. The result is a second cutting model that can be optimized for machining sequence. Based on the second cutting model, subsequent grouping and route optimization are performed, which makes the generated machining process conform to reality, while reducing the time wasted due to frequent switching of tool heads and tool head angles, shortening the machining time and increasing the machining efficiency.

[0024] Furthermore, the preset splitting rules are configured with several basic 3D models. Each basic 3D model is a single geometric object and cannot be further split into a combination of single geometric objects of other basic 3D models. During the splitting process, the following conditions must also be met: The area of ​​each simple structural 3D model after decomposition accounts for more than or equal to 5% of the surface area of ​​the second cutting 3D model. The angle between each of the decomposed simple structure 3D models and other simple structure 3D models is less than or equal to 30°.

[0025] In detail, by using preset splitting rules, the overall second cutting 3D model is split into several simple structures. By displaying the included angles of the structural components, the machining directions are made similar, reducing the time wasted by angle switching. This facilitates the subsequent division of the simple structure 3D model based on the tool head, thereby forming several sets of models with similar angles and the same tool head type. This reduces the time wasted by frequent tool head switching and tool head angle changes, shortens machining time, and increases machining efficiency.

[0026] Furthermore, the angle between the feed direction and the initial feed direction of each simple structural 3D model, as well as the feed position coordinates of each simple structural 3D model, are obtained, including: Obtain the feed direction and initial feed direction of each simple structure 3D model, establish a feed vector and an initial feed vector with a length of unit length and directions of feed direction, respectively, calculate the angle between the feed vector and the initial feed vector and record it as the transformation angle; The coordinates of the point on each simple structure 3D model that is closest to the reference structure after machining are obtained are used as the tool entry position coordinates of each simple structure 3D model.

[0027] It should be noted that, in this embodiment of the invention, the unit length is only used to calculate the angle between the feed vector and the initial feed vector. The unit length should be chosen for ease of calculation; in this embodiment, the unit length is 1 cm. The angle between the feed vector and the initial feed vector is obtained through the dot product operation. The dot product operation is a fundamental mathematical concept, and those skilled in the art can derive the angle between the feed vector and the initial feed vector based on the description of this technical solution. The coordinates of the point closest to the reference structure on the three-dimensional model of each simple structure after machining can be intuitively obtained through the three-dimensional model, and will not be elaborated further here.

[0028] Furthermore, based on the infeed angle and infeed position of each simple structural 3D model, the tool head movement score is calculated, including: Obtain the transformation angle and the tool entry position coordinates of each simple structural 3D model; The distance between the point coordinates of the tool head coordinates after the machining of the reference structure is completed and the tool entry position coordinates of each simple structure 3D model is recorded as the tool head displacement distance. Assign corresponding weight coefficients to the conversion angle and the tool head displacement distance, calculate the sum of the products of the conversion angle and the tool head displacement distance and the corresponding weight coefficients, and record it as the tool head movement score.

[0029] It should be noted that the formula for calculating the cutter head movement score α is: ;in: To change the angle, This is the weighting coefficient for the cutter head angle. This represents the displacement distance of the cutting head. The weighting coefficients are: cutter head displacement distance and cutter head angle. and the weighting coefficient of the tool displacement distance The value is configured by the system and During the calculation process, it is necessary to first convert the angle. and the displacement distance of the cutter head Normalization is performed to eliminate the effects caused by different dimensions.

[0030] In detail, this invention calculates the transformation angle using spatial vectors, allowing the acquisition of the included angle to be directly calculated without being restricted by coplanarity. A weighted cutter head movement score is calculated based on the cutter head displacement distance and transformation angle. The smaller the weighted cutter head movement score, the less time is wasted due to the cutter head displacement distance and transformation angle during actual machining. The next optimal simple structure 3D model to be machined is selected, and the weighted cutter head movement score is calculated based on this next optimal simple structure 3D model. This process continues until the first cutting path corresponding to the first model set is obtained. This reduces the time wasted due to frequent cutter head and cutter head angle switching, shortens machining time, and increases machining efficiency.

[0031] Furthermore, the external proportion of each model set in the third cutting 3D model is calculated, including: For a single model set, obtain the area of ​​the surface of each simple structure 3D model in the model set on the outer surface of the third cutting 3D model and record it as the exposed area. The ratio of the exposed area to the outer surface area of ​​the third cutting 3D model is recorded as the external proportion.

[0032] This invention calculates the external proportion and prioritizes the processing of exposed model components, avoiding cutting interference caused by processing the internal parts first during part processing. The larger the exposed area, the better the processing effect, which helps to increase processing stability.

[0033] Furthermore, the machining process is generated based on the cutting paths corresponding to all simple structural 3D model sets, including the generation of cutting paths for the reference structure, including: The point on the reference structure closest to the initial position of the tool head before machining the part is selected as the infeed position of the reference structure, and the cutting path of the reference structure is generated by using a helical infeed method.

[0034] It should be noted that during the process of generating the cutting path of the reference structure using the helical feed method, the helical radius and helix angle are adaptively adjusted according to the actual situation. After the cutting is completed, the tool head stops at the end point of the reference structure, which serves as the starting point for subsequent machining.

[0035] Furthermore, after obtaining the 3D model of the finished part and the 3D model of the blank, a model preprocessing process is also included, including: The coordinates of the finished part 3D model and the blank 3D model are aligned. The bottom surface, internal center line or external edge line of the blank 3D model are used as positioning references to construct a 3D coordinate system and project the finished part 3D model into the 3D coordinate system. Leave a machining allowance of 0.5 to 5 mm on the surface of the part before performing the Boolean difference operation.

[0036] Furthermore, the coordinates of the finished part's 3D model and the blank's 3D model are aligned to avoid machining errors. The reserved machining allowance is the allowance for subsequent finishing, ensuring the part's pass rate.

[0037] Furthermore, embodiments of the present invention also provide an automatic generation system for part machining processes using a three-dimensional model, comprising: The model building unit obtains the 3D model of the finished part and the 3D model of the blank, and combines Boolean difference set operation to obtain the 3D model of the part of the blank that needs to be cut off during the part processing. The model splitting unit obtains the reference structure during the part machining process and determines the first cutting three-dimensional model. Based on the three-dimensional model to be cut and the first cutting three-dimensional model, the second cutting three-dimensional model is determined. The second cutting three-dimensional model is split according to the preset splitting rules to form several simple structural three-dimensional models. The determination unit classifies the three-dimensional models of each simple structure according to the type of the cutting head corresponding to each simple structure three-dimensional model to obtain several model sets. In response to the existence of a first model set with the same cutting head type as the reference structure, the first operation unit is run. If no such set exists, the second operation unit is run directly. The first processing unit, for the first model set with the same tool head type and reference structure, obtains the infeed angle between the infeed direction and the initial infeed direction of each simple structure 3D model, as well as the infeed position coordinates of each simple structure 3D model. Based on the infeed angle and infeed position of each simple structure 3D model, it calculates the tool head movement score, selects the simple structure 3D model with the lowest tool head movement score as the next infeed position, and repeats this step until the first cutting path corresponding to the first model set is generated; The second processing unit obtains the third cutting 3D model after the first model set has been processed, calculates the external proportion of each model set in the third cutting 3D model, determines the generation order of the corresponding routes for each model set according to the external proportion from high to low, selects the infeed position of the simple structure 3D model closest to the tool change position as the initial infeed position for a single model set, calculates the tool head movement score based on the infeed angle and infeed position of each simple structure 3D model, selects the simple structure 3D model with the lowest tool head movement score as the next infeed position, until the cutting route corresponding to a single model set is generated, and repeats this step according to the generation order to obtain the cutting routes corresponding to all model sets; The output unit generates the machining process based on the cutting paths corresponding to all model sets.

[0038] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0039] Alternatively, if the integrated units of this invention are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this invention, or the parts that contribute to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROM, RAM, magnetic disks, or optical disks.

Claims

1. A method for automatically generating part machining processes using a three-dimensional model, characterized in that, include: Step S1: Obtain the 3D model of the finished part and the 3D model of the blank. Combine Boolean difference set operation to obtain the 3D model of the blank that needs to be cut off during the part processing. Step S2: Obtain the reference structure during the part machining process and determine the first cutting three-dimensional model. Determine the second cutting three-dimensional model based on the three-dimensional model to be cut and the first cutting three-dimensional model. Decompose the second cutting three-dimensional model according to the preset splitting rules to form several simple structure three-dimensional models. Step S3: Classify the three-dimensional models of each simple structure according to the type of the cutting head corresponding to each simple structure three-dimensional model to obtain several model sets. If there is a first model set with the same cutting head type as the reference structure, execute step S4. If not, directly execute step S5. Step S4: For the first set of models with the same tool head type and reference structure, obtain the infeed angle between the infeed direction and the initial infeed direction of each simple structure 3D model, as well as the infeed position coordinates of each simple structure 3D model. Calculate the tool head movement score based on the infeed angle and infeed position of each simple structure 3D model, select the simple structure 3D model with the lowest tool head movement score as the next infeed position, and repeat this step until the first cutting path corresponding to the first set of models is generated. Step S5: Obtain the third cutting 3D model after the first model set has been processed. Calculate the external proportion of each model set in the third cutting 3D model. Determine the generation order of the corresponding routes for each model set according to the external proportion from high to low. For a single model set, select the entry position of the simple structure 3D model that is closest to the tool change position as the initial entry position. Calculate the tool head movement score based on the entry angle and entry position of each simple structure 3D model. Select the simple structure 3D model with the lowest tool head movement score as the next entry position until the cutting route corresponding to a single model set is generated. Repeat this step according to the generation order to obtain the cutting routes corresponding to all model sets. Step S6: Generate machining process based on the cutting paths corresponding to all model sets; The reference structure is a geometric feature that can provide a reference for subsequent machining positioning.

2. The method for automatically generating part machining processes using a three-dimensional model according to claim 1, characterized in that, The process involves acquiring the reference structure during part machining and mapping it to the three-dimensional model to be cut, determining the first three-dimensional model for cutting, determining the second three-dimensional model for cutting based on the three-dimensional model to be cut and the first three-dimensional model for cutting, mapping the reference structure to the three-dimensional model to be cut, acquiring the three-dimensional model of the blank that needs to be cut off during the machining of the reference structure, using Boolean difference operations to remove the three-dimensional model of the blank that needs to be cut off during the machining of the reference structure from the three-dimensional model to be cut, and recording the three-dimensional model obtained after removal as the second three-dimensional model for cutting.

3. The method for automatically generating part machining processes using a three-dimensional model according to claim 2, characterized in that, The preset splitting rules are configured with several basic 3D models. Each basic 3D model is a single geometric object and cannot be further split into a combination of single geometric objects of other basic 3D models. During the splitting process, the following conditions must also be met: The area of ​​each simple structural 3D model after decomposition on the outer surface of the second cutting 3D model accounts for more than or equal to 5% of the surface area of ​​the second cutting 3D model; The angle between each of the decomposed simple structure 3D models and other simple structure 3D models is less than or equal to 30°.

4. The method for automatically generating part machining processes using a three-dimensional model according to claim 1, characterized in that, Obtain the infeed angle between the infeed direction and the initial infeed direction for each simple structural 3D model, as well as the infeed position coordinates for each simple structural 3D model, including: Obtain the feed direction and initial feed direction of each simple structure 3D model, establish a feed vector and an initial feed vector with a length of unit length and directions of feed direction, respectively, calculate the angle between the feed vector and the initial feed vector and record it as the transformation angle; The coordinates of the point on each simple structure 3D model that is closest to the reference structure after machining are obtained are used as the tool entry position coordinates of each simple structure 3D model.

5. The method for automatically generating part machining processes using a three-dimensional model according to claim 4, characterized in that, The calculation of the tool head movement score based on the infeed angle and infeed position of each simple structural 3D model includes: Obtain the transformation angle and the tool entry position coordinates of each simple structural 3D model; The distance between the point coordinates of the tool head coordinates after the machining of the reference structure is completed and the tool entry position coordinates of each simple structure 3D model is recorded as the tool head displacement distance. Assign corresponding weight coefficients to the conversion angle and the cutter head displacement distance respectively, calculate the sum of the products of the conversion angle and the cutter head displacement distance and the corresponding weight coefficients, and record it as the cutter head movement score.

6. The method for automatically generating part machining processes using a three-dimensional model according to claim 1, characterized in that, The calculation of the external proportion of each model set in the third cutting 3D model includes: For a single model set, the area of ​​the surface of each simple structure 3D model in the model set on the outer surface of the third cutting 3D model is obtained and recorded as the exposed area. The ratio of the exposed area to the outer surface area of ​​the third cutting 3D model is recorded as the external proportion.

7. The method for automatically generating part machining processes using a three-dimensional model according to claim 1, characterized in that, The machining process is generated based on the cutting paths corresponding to all the simple structural 3D model sets, and also includes the generation of cutting paths for the reference structure, including: The point on the reference structure closest to the initial position of the tool head before machining the part is selected as the infeed position of the reference structure, and the cutting path of the reference structure is generated by using a helical infeed method.

8. The method for automatically generating part machining processes using a three-dimensional model according to claim 1, characterized in that, After obtaining the 3D model of the finished part and the 3D model of the blank, the process also includes model preprocessing, including: The coordinates of the finished part 3D model and the blank 3D model are aligned. The bottom surface, internal center line or external edge line of the blank 3D model are used as positioning references to construct a 3D coordinate system and project the finished part 3D model into the 3D coordinate system. Leave a machining allowance of 0.5 to 5 mm on the surface of the part before performing the Boolean difference operation.

9. An automatic part machining process generation system using a three-dimensional model, used to implement the automatic part machining process generation method using a three-dimensional model as described in any one of claims 1-8, characterized in that, include: The model building unit obtains the 3D model of the finished part and the 3D model of the blank, and combines Boolean difference set operation to obtain the 3D model of the part of the blank that needs to be cut off during the part processing. The model splitting unit obtains the reference structure during the part processing and determines the first cutting three-dimensional model. Based on the three-dimensional model to be cut and the first cutting three-dimensional model, it determines the second cutting three-dimensional model. According to the preset splitting rules, the second cutting three-dimensional model is split to form several simple structure three-dimensional models. The determination unit classifies the three-dimensional models of each simple structure according to the type of the cutting head corresponding to each simple structure three-dimensional model to obtain several model sets. In response to the existence of a first model set with the same cutting head type as the reference structure, the first operation unit is run. If no such set exists, the second operation unit is run directly. The first processing unit, for the first model set with the same tool head type and reference structure, obtains the infeed angle between the infeed direction and the initial infeed direction of each simple structure 3D model, as well as the infeed position coordinates of each simple structure 3D model. Based on the infeed angle and infeed position of each simple structure 3D model, it calculates the tool head movement score, selects the simple structure 3D model with the lowest tool head movement score as the next infeed position, and repeats this step until the first cutting path corresponding to the first model set is generated; The second processing unit obtains the third cutting 3D model after the first model set has been processed, calculates the external proportion of each model set in the third cutting 3D model, determines the generation order of the corresponding routes for each model set according to the external proportion from high to low, selects the infeed position of the simple structure 3D model closest to the tool change position as the initial infeed position for a single model set, calculates the tool head movement score based on the infeed angle and infeed position of each simple structure 3D model, selects the simple structure 3D model with the lowest tool head movement score as the next infeed position, until the cutting route corresponding to a single model set is generated, and repeats this step according to the generation order to obtain the cutting routes corresponding to all model sets; The output unit generates a machining process based on the cutting paths corresponding to all the model sets.

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