Patent Publication Number: US-2022214654-A1

Title: Processing method and system for automatically generating machining feature

Description:
This application claims the benefit of Taiwan application Serial No. 110100257, filed Jan. 5, 2021, the subject matter of which is incorporated herein by reference. 
     BACKGROUND OF THE DISCLOSURE 
     Field of the Disclosure 
     The disclosure relates in general to a processing method and a system for automatically generating machining features. 
     Description of the Related Art 
     Most of the computer aided design/manufacturing (CAD/CAM) based machining path programming software requires those who are versed with the manufacturing process to perform manual feature selection to plan a machining path that meets the requirements of machining cost. Despite already having the function of blank reference and tool reference, the currently available CAD/CAM based machining path programming software is still unable to automatically select the machining features. To overcome the problems encountered in the automation and optimization of path programming, the machining features required in the programming of machining path needs to be analyzed to meet the requirements of machining cost and production efficiency. 
     SUMMARY OF THE DISCLOSURE 
     The disclosure is directed to a processing method and a system for automatically generating machining features capable of identifying machining features and improving the conventional manufacturing process, meanwhile, providing suitable tool analysis as a machining basis for the complete machining process. 
     According to one embodiment of the present disclosure, a processing method for automatically generating machining features is provided. The processing method includes following steps. A workpiece CAD file is obtained to perform a CAD numerical analysis on a blank body. With the workpiece CAD file being used as a target, a workpiece CAD appearance is compared with the blank body to obtain a feature identification result of a first to-be-processed blank body, wherein the feature identification result of the first to-be-processed blank body includes identifying data of a to-be-removed blank body and a feature of a first processing surface. A geometric analysis is performed on the feature of the first processing surface and a tool selection range is determined. A virtual cutting simulation is performed on the first processing surface according to the tool selection range to generate a processed area data and an unprocessed area data. A spatial coordinate mapping comparison between the unprocessed area data and a surface data of the workpiece CAD file is performed to obtain a feature identification result of a second to-be-processed blank body. 
     According to another embodiment of the present disclosure, a processing system for automatically generating machining features is provided. The processing system includes a blank body identification module, a geometric data analysis module, a machining tool analysis module and a cutting simulation module. The blank body identification module is used to obtain a workpiece CAD file to perform a CAD numerical analysis on a blank body, and, with the workpiece CAD file being used as a target, compare a workpiece CAD appearance with the blank body to obtain a feature identification result of a first to-be-processed blank body, wherein the feature identification result of the first to-be-processed blank body includes identifying data of a to-be-removed blank body and a feature of a first processing surface. The geometric data analysis module performs a geometric analysis according to the feature of the first processing surface. The machining tool analysis module is used to confirm the tool selection range for processing the first processing surface. The cutting simulation module is used to perform a virtual cutting simulation on the first processing surface according to the tool selection range to generate a processed area data and an unprocessed area data. Besides, the blank body identification module performs a spatial coordinate mapping comparison between the unprocessed area data and a surface data of the workpiece CAD file to obtain a feature identification result of a second to-be-processed blank body. 
     The above and other aspects of the disclosure will become better understood with regard to the following detailed description of the preferred but non-limiting embodiment(s). The following description is made with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of a processing system for automatically generating machining features according to an embodiment of the present disclosure; 
         FIG. 2  is a schematic diagram of a processing method for automatically generating machining features according to  FIG. 1 ; 
         FIG. 3  is a schematic diagram of a processing system for automatically generating machining features according to another embodiment of the present disclosure; 
         FIGS. 4A and 4B  are schematic diagrams of a processing method for automatically generating machining features according to  FIG. 3 ; and 
         FIG. 5  is a schematic diagram of a system for automatically generating machining features according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     Detailed descriptions of the disclosure are disclosed below with a number of embodiments. However, the disclosed embodiments are for explanatory and exemplary purposes only, not for limiting the scope of protection of the disclosure. Similar/identical designations are used to indicate similar/identical elements. Directional terms such as above, under, left, right, front or back are used in the following embodiments to indicate the directions of the accompanying drawings, not for limiting the present disclosure. 
     Refer to  FIGS. 1 and 2 .  FIG. 1  is a schematic diagram of a processing system  10  for automatically generating machining features according to an embodiment of the present disclosure.  FIG. 2  is a schematic diagram of a processing method for automatically generating machining features according to  FIG. 1 . Descriptions of the symbols and designations of relevant elements disclosed below can be obtained reference to  FIGS. 1, 2 and 5 . 
     According to an embodiment of the present disclosure, the processing system  10 , such as a CAD/CAM machining path programming software and a computer related equipment, includes a blank body identification module  20 , a geometric data analysis module  30 , a machining tool analysis module  40 , a cutting simulation module  50  and a tool database  60 . The blank body identification module  20  is used to obtain a workpiece CAD file  11  to perform a CAD numerical analysis  101  on a blank body  100 . According to the numerical analysis, a continuous area is converted into discrete subareas using grid discretization or decomposed into a finite number of triangular subareas using a finite element method. 
     The workpiece CAD file  11  may include the physical data, surface data and line data of a workpiece  110 . The physical data includes the volume, coordinates and surface relevance of the workpiece  110 . The surface data includes the area, normal vector, coordinates and edge correlation of the processing surface. The line data includes the end points, coordinates and adjacent surfaces of the edges of the workpiece  110 . 
     Refer to  FIGS. 1 and 2 . After the processing system  10  obtains a workpiece CAD file  11 , in step S 1 , the corresponding spatial data and numeric data of the blank body  100  are calculated by the blank body identification module  20  according to a workpiece CAD appearance. In step S 2 , with the workpiece CAD file  11  being used as a target, the workpiece CAD appearance is compared with the blank body  100  to obtain a feature identification result of a first to-be-processed blank body, wherein the feature identification result of the first to-be-processed blank body  100  includes identifying data of a to-be-removed blank body  100   a  (represented by slashes) and a feature of a first processing surface  111 . 
     In step S 3 , the surface data of the workpiece CAD file  11  is compared with the spatial data of the first to-be-processed blank body  100  to obtain the scope and feature of the first processing surface  111 . The feature of the first processing surface  111  includes the type, normal vector, coordinate range, curvature, intersecting surface, and edge relevance of the processing surface. In step S 4 , a geometric analysis  102  is performed by the geometric data analysis module  30  according to the feature of the first processing surface  111 , wherein the geometric analysis  102  includes obtaining at least one of the geometric pattern data  112 ,  113  and  114  including the bottom area, bottom classification, sidewall right angle and curvature of the first processing surface. 
     In step S 5 , a tool data is selected from the tool database  60  by the machining tool analysis module  40  to confirm a tool selection range for processing the first processing surface of the blank body  100 . That is, different processing surface features correspond to different tool selection ranges. Also, in step S 6 , a virtual cutting simulation  103  is performed on the first processing surface  111  by the cutting simulation module  50  according to the selected tool to generate data of a processed area  115  and data of an unprocessed area  116 . 
     In step S 7 , a spatial coordinate mapping comparison  105  between the data of the unprocessed area  116  and the surface data of the workpiece CAD file  11  is performed by the blank body identification module  20  to obtain a feature identification result of a second to-be-processed blank body  100 , wherein the feature identification result of the second to-be-processed blank body  100  includes identifying a processable residual area feature. 
     According to the processing method and system of the present embodiment, an appearance of the blank body  100  is compared with the surface data of the workpiece CAD file  11  through the CAD numerical analysis  101 , the processing surface geometric analysis  102 , the cutting simulation analysis  103  and the unprocessed area residual feature analysis  104  to obtain a feature identification result of a first to-be-processed blank body  100 , then the data of an unprocessed area  116  is further compared with the surface data of the workpiece CAD file  11  to obtain a feature identification result of a second to-be-processed blank body  100 . Then, the CAD/CAM based machining path programming software of the processing system  10  further plans a machining path for automatically generating a machining process  51  corresponding to the machining path according to the feature identification result of the first to-be-processed blank body  100  and the feature identification result of the second to-be-processed blank body  100 . 
     In comparison to the conventional method for manually selecting the feature selection, the processing system  10  and method of the present embodiment possess the function of automatically selecting machining features, not only resolving the problem of tool-lifting efficiency caused by the blank reference but also providing suitable tool analysis as a machining basis for automatically generating the machining process  51 . 
     Refer to  FIG. 3  and  FIGS. 4A and 4B .  FIG. 3  is a schematic diagram of a processing system  10 ′ for automatically generating machining features according to another embodiment of the present disclosure.  FIGS. 4A and 4B  are schematic diagrams of a processing method for automatically generating machining features according to  FIG. 3 . 
     The processing system  10 ′ of the present embodiment is similar to the processing system  10  of the above embodiment except that the processing system  10 ′ of the present embodiment further includes a special geometric database  70  in addition to the blank body identification module  20 , the geometric data analysis module  30 , the machining tool analysis module  40 , the cutting simulation module  50  and the tool database  60 . The special geometric database  70  stores the special geometric pattern data. The geometric data analysis module  30  compares the tool database  60  with the special geometric database  70  according to the first processing surface feature  111  to obtain a feature identification result of a third to-be-processed blank body  100 , wherein the feature identification result of the third to-be-processed blank body  100  includes identifying a tool-replaceable processing area feature or a processing area feature corresponding to a special tool. 
     As indicated in  FIGS. 4A and 4B , the processing method further includes step S 8  and step S 9  in addition to steps S 1  to S 7  disclosed above. In step S 8 , the special geometric processed area analysis includes comparing the special geometric database  70  by the geometric data analysis module  30  according to the feature of the first processing surface  111  to obtain a feature identification result of a third to-be-processed blank body  100 , wherein the feature identification result of the third to-be-processed blank body  100  includes identifying a tool-replaceable processing area feature or a processing area feature corresponding to a special tool to determine whether to perform a tool replacement process. Therefore, the machining tool analysis module  40  can select the tool according to the result of special geometric analysis. For example, the end milling cutter can be replaced with a flat milling cutter, a round nose milling cutter, a ball milling cutter, or other special purpose cutter to perform a special machining process. 
     In step S 9  as indicated in  FIG. 4B , the CAD/CAM based machining path programming software of the processing system  10 ′ plans a special machining path (or a special machining process) for automatically generating a special machining process  51  corresponding to a special machining path (or special machining process) according to the feature identification result of the first to-be-processed blank body  100 , the feature identification result of the second to-be-processed blank body  100  and the feature identification result of the third to-be-processed blank body  100 . 
     Referring to  FIG. 5 , a schematic diagram of a system for automatically generating machining features according to an embodiment of the present disclosure is shown. As indicated by the arrows, the steps for automatically generating machining features include a CAD numerical analysis  101 , a processing surface geometric analysis  102 , a cutting simulation analysis  103 , an unprocessed area residual feature analysis  104  and a spatial coordinate mapping comparison  105 . 
     As indicated in  FIG. 5 , the blank body  100  can be formed by a workpiece blank, which corresponds to a workpiece CAD appearance. The CAD numerical analysis  101  can be performed to obtain the spatial data of the workpiece blank according to the maximum tolerance range of the blank body  100  obtained through the calculation of the physical data and surface data of the workpiece CAD appearance. As disclosed in step S 1 , the spatial data and numeric data of the corresponding blank body  100  are calculated according to the workpiece CAD appearance. Then, in step S 2 , with the workpiece CAD file  11  being used as a target, the workpiece CAD appearance is compared with the blank body  100  to obtain a feature identification result of a first to-be-processed blank body  100 , wherein the feature identification result of the first to-be-processed blank body  100  includes identifying data of a to-be-removed blank body  100   a  (the slashed area represents the scope of the to-be-removed blank body  100   a ). 
     The first processing surface  111  can be a bottom surface of a groove and/or a vertical sidewall. The processing surface geometric analysis  102  includes obtaining the geometric pattern data  112 ,  113  and  114 , such as the physical data, surface data and line data of the to-be-processed first processing surface  111 . As disclosed in step S 3 , the surface data of the workpiece CAD file  11  is compared with the spatial data of the first to-be-processed blank body  100  to obtain the scope and feature of the first processing surface  111 . The feature of the first processing surface  111  includes the type, normal vector, coordinate range, curvature, intersecting surface, and edge relevance of the processing surface. 
     The tool  117  can be a milling cutter, such as an end milling cutter, a flat milling cutter, a round nose milling cutter, a ball milling cutter, or other special purpose cutter. According to the cutting simulation analysis  103 , the tool  117  suitable for processing the first processing surface of the blank body  100  is selected, and a virtual cutting simulation is performed on the first processing surface  111  by the selected tool  117  to generate data of a processed area  115  and data of an unprocessed area  116  (as disclosed in step S 6 ). The processed area  115  is the first processing surface that has been removed, and the unprocessed area  116  is the first processing surface that has not been removed after the spatial coordinate mapping comparison  105  is performed, that is, the unprocessed area  116  is a residual area. 
     As indicated in step S 7 , according to the residual feature analysis  104  of the unprocessed area  116 , a spatial coordinate mapping comparison  105  between the data of the unprocessed area  116  and the surface data of the workpiece CAD file  11  is performed to obtain an identification result. If the identification result determines that the unprocessed area  116  is a processable residual area, a suitable tool  117  is selected by the machining tool analysis module  40  and a virtual cutting simulation is performed to the unprocessed area  116  by the selected tool  117 , wherein the result of the virtual cutting simulation is used as a machining basis for automatically generating a machining process  51 . 
     In  FIG. 5 , when the unprocessed area  116   a  is determined as a processable residual area, a tool data is selected according to the feature of the processable residual area to confirm a selected tool  117  for performing a second processing on the processable residual area. For example, the tool selection range can be changed to a round nose milling cutter or a ball milling cutter from an end milling cutter to plan a tool replacement process for the second machining process. Moreover, if the unprocessed area  116   b  is determined as a processable residual area, the tool selection range can be changed to a flat milling cutter from an end milling cutter according to the appearance of the residual area to plan a tool replacement process for the second machining process. 
     According to the processing method and the system for automatically generating machining features disclosed in above embodiments of the present disclosure, a residual numerical analysis is performed on an unprocessed residual area to determine whether the residual area has a processable residual area feature. Conventionally, path planning is based on the simulation residual of the previous process. However, when the resolution of residual operation and the feature of previous tool are insufficient, the generated machining path has an insufficient level of consistency, and the machining process has an insufficient degree of automation and affects the efficiency of the manufacturing process. For example, the tool is lifted repeatedly, the surface pattern is poor, and the tool lifting time is too long. The processing method and system for automatically generating machining features of the present disclosure can overcome the problems encountered in the automation and optimization of path programming and meet the requirements of machining cost and production efficiency. 
     While the disclosure has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the disclosure is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.