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Research on cad/capp/cam system integration based on pro/e platform

Abstract: in view of the fact that the application of pro/e software is mostly focused on its CAD function, but the cam function of pro/e is not fully applied, and there are problems of repeated work in many design processes in the application of CAD function, this paper studies the general method of cad/capp/cam integration by using pro/e secondary development tool pro/toolkit under pro/e system, The development of application user interface using MFC class library of VC ++6.0 is realized by using dynamic link library (DLL). The detailed design scheme is given from the aspects of the overall design of the system and the construction of each functional module, which realizes the automatic processing of relevant processes and improves the practical application of pro/e system

key words: cad/capp/cam; Pro/E; Secondary development; The design scheme

pro/e is a cad/cam software package developed by American parameterization Corporation (PTC), and pro/toolkit is a pro/e secondary development tool specially provided by PTC. In pro/toolkit, PTC provides users with a large c language function library. By calling these underlying functions, users can easily and safely access the pro/e database and internal applications, carry out secondary development, and expand some specific functions

1 overall structure design of the system

in terms of function, each module of the system is only a further encapsulation of the main functions of pro/e using the idea of object-oriented. Its purpose is to simplify the times of human-computer interaction and make the system easier to operate and learn. The relationship between the modules is shown in Figure 1

Figure 1 overall structure of the system

all modules are independent pro/toolkit applications. The communication between modules is realized by the interface function provided by pro/toolkit. The relevant E. test results can be transferred by the data situation output parameters in Excel format using pro/toolkit functions and related pointers

the design and machining information of the whole part is stored in the pro/e database. Since pro/e is a software system based on a single database, any modification at any place will cause changes in all relevant parameters, which makes it very convenient to modify the model

when the system finds problems in the simulation phase, the user can modify the process settings or directly modify the product geometric model, and then verify the rationality of the design through the simulation phase. After the simulation results of the machining path meet the design requirements, the NC machining code can be generated through the post-processing module

2 design and implementation of each functional module

2.1 modeling module

the function of this module is to realize the structural design of parts, and its goal is to generate a file that stores the overall information of parts

the core of this module is to establish a feature library. Firstly, according to the actual production situation, the structure and processing conditions of the parts are analyzed and summarized according to the GT technology method, and finally the type and quantity of features are determined. The classification of features is shown in Figure 2

Figure 2 feature classification figure

the establishment of geometric features is realized by using the user-defined feature function provided by pro/e [2, 3]. The process of creating each geometric feature is similar, that is, first build the product model manually, attach the feature to be created to the model, and then select the menu item to create the geometric feature. The definition of a geometric feature should include reference datum, variable dimension and mark of variable dimension. By modifying the value of variable parameters in the program, the required feature derivatives can be obtained. In the process of modeling, the mouse can also be used to select the dimension, and the dimension driven technology can be used to modify these parameters. Non geometric features are stored in the form of feature codes. Finally, all features are stored in the same root directory in the same format (.Gph) to form a feature library (udflibrary) as a basic tool for modeling

in the application, firstly, the feature library is used to establish the geometric type, and then according to the different machining requirements for each geometric feature, the non geometric feature is added to each feature to form a complete description of the part information. The communication between geometric features and non geometric features is realized by means of pointers

the model is established by the feature assembly technology which is completely consistent with the pro/e system modeling idea. Firstly, the main features of the geometric model are selected as the parent features of the whole model, and the other features are selected from the feature library and attached to the main features to form the basic shape of the model; Then the variable dimension of each feature is modified according to the design requirements, and the geometric model of the part is established; Finally, non geometric features are added. The methods are as follows: 1) select the "add non geometric feature" item in the customization menu with the mouse, pop up the setting dialog box and fix it on the desktop; 2) Select the geometric features with the mouse in turn, and make its relevant pointer items point to the dialog box; 3) Assign values to the parameters in the dialog box. This process is also the assignment of parameters related to the selected feature. At this point, the modeling of the part is completed, and all settings are stored in the specified location as files as input parameters of the CAPP part

2.2 process processing module and machining simulation

the main function of the process processing module is to automatically obtain the machining parameters of the system by cam. Its goal is to generate the tool position data file after the machining simulation is completed, which is used as the input of post-processing. Its basic composition and 5 The mutual relationship can be tested after the cover plate is covered, as shown in Figure 3

figure by 2018, the domestic NCA material demand will break through the kiloton 3 process processing module block diagram

obviously, the establishment of the manufacturing model is the starting point of the whole work. First, the manufacturing model establishment module reads the files generated by the modeling module through its own pointer function, and then automatically selects the blanks from the blank library according to the relevant rules of the blank selection rule library, and automatically completes the establishment of the manufacturing model, Thus, the fully automatic operation of manufacturing model establishment is realized

process planning is the core of this part and also the difficulty of the whole secondary development. In view of the lack of CAPP information integration in the pro/e system itself, the user's setting of various machining features, the selection of machining methods, the selection of cutting tools, and the setting of cutting parameters all need to be completed by human-computer interaction. These operations have high requirements for operators and complex interaction, which is one of the main reasons that limit the wide application of pro/e's cam function. Therefore, the system puts forward the following solutions

first, input process equipment information in an interactive way, such as fixture and machine tool information. Then enter the reasoning link. The reasoning steps are as follows: 1) read the modeling file, and automatically generate the processing procedure of each feature according to the process reasoning rules established for each feature; 2) Combined with the output information of the manufacturing model, the machining processes of all features are automatically integrated and sorted, and the tool position file of the whole part machining is generated. Among them, the processing parameters, tool selection and cutting parameters of rough machining, semi finishing, finishing and other processes are determined in the reasoning link, and the tool withdrawal surface, tool feeding mode, tool feeding and withdrawing mode and tool feeding times are determined in the sorting process. Input the reasoning results into the pro/nc check module for tool path simulation to check whether the settings are reasonable and whether there is interference. Users can modify the geometric model or modify the settings of machining parameters to make the simulation results more in line with the design requirements. After the simulation results meet the machining requirements, the final tool position file is generated

2.3 post processing

use the post-processing function module of pro/e to convert the tool position file into the NC code that can be recognized by the machine tool

3 development of user interface

because pro/e has always used the UNIX of the workstation as the development and use environment, the interface style is more similar to xwindows than AutoCAD, which is completely consistent with the windows style. At the same time, the dialog box controls provided by pro/e are also very limited. Therefore, the system uses the MFC class library of vc++6.0 to develop the user interface [1, 3]. At the same time, it also uses vc++ to develop the relevant database. The essence of development is to call the MFC application program in the pro/e system. In the development, dynamic link library (DLL) is used to realize the communication among pro/e system, pro/toolkit application program and MFC application program. Because the communication is realized by directly calling functions, it has the characteristics of fast execution [4]. The relationship among the three is shown in Figure 4

Figure 4 Schematic diagram of the connection between pro/toolkit and MFC

a dialog interface is developed for each pro/toolkit application in the system. After the application is loaded into the pro/e system, click the customized menu item to call the secondary development module and its interface, so as to make the design process more in line with the thinking habits of designers

4 example

in order to illustrate the operation of the system, an example of a stepped shaft is made. Such a stepped shaft is assembled from the shape features (cylinder and cone) through multiple calls. The modeling process is no longer discussed. In the modification process, different processing schemes can be obtained by adding different non geometric features. The operation block diagram is shown in Figure 5

Figure 5 part processing flow chart

5 conclusion

under the condition of making full use of the resources provided by pro/e system, the cad/capp/cam integration is realized by using the secondary development tool pro/toolkit provided by pro/e and the vc++6.0 integrated development environment, which simplifies the operation of the cam module of pro/e system, and provides some experience for the integration research of special cad/capp/cam

thank you: This article has been supported by the characteristic research direction fund of Lanzhou University of technology


[1] kruglinski dj Visual c++6.0 technology insider [m]. Beijing: Hope Electronic Publishing House, 1998

[2] Huang Shengjie, Zhang Yisan Pro/engineer 2001 advanced development example [m]. Beijing: Electronic Industry Press, 2002

[3] laichaoan, lizhenan, sunyanming, et al Key technologies of pro/e secondary development [j] Mechanical design and manufacturing, 2001, (1):43 45

[4] zhongjianlin Pro/engineer NC machining practical tutorial [m] Beijing: China Machine Press, 2002

[5] Wang Zheng, Dang Junfeng, xuwentao Development of WFCAD system menu based on pro/e [j] Journal of Gansu University of technology, 2003, 29 (1):2628

[6] huchibing, yanshutian, wuzaixin Automatic programming of gear processing parameters [j the boundary of different colors should be clear] Machinist, 1998, (7):1819

[7] Yang Ping, zhangshuzhen, liheqi, et al Shape fitting and solid model establishment of Francis Turbine Runner Blade Based on pro/e software platform [j] Mechanical design and manufacturing, 2002, (6):6263

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