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In this article, an application in the field of engineering graphics is presented for the design of a geometric calculator generated as a macro in CATIA V5. The code of this macro is written in the CATVBA language and utilizes the CATIA internal editor while taking advantage of the capabilities offered by Visual Basic for Applications (VBA). The principal purpose of this application lies in the possibility of creating the three main geometric elements (point, line, and plane) and in solving five types of general geometric problems, and then comparing the results obtained with their equivalent problems from analytical geometry. In particular, within these types of general geometric problems, 34 possible cases are solved: definition of lines (nine cases), definition of planes (12 cases), intersection points (three cases), angles (three cases), and distances (seven cases). These new entities defined with the geometric calculator can serve as support for the generation of new three-dimensional volumes, the creation of auxiliary symmetries, and the dimensioning of various elements. It was verified that the results of the designed macro and the solutions of the analytical equations coincided; therefore, the procedure was validated. Likewise, the module employed herein in the CATIA V5 environment is "Wireframe and Surface Design", since it enables handling the three basic geometric elements (point, line, and plane), which form the basis of the geometric calculator. Lastly, it is verified how the geometric calculator allows their integration with three-dimensional solids, which represents a notable advance as an aid in its geometric definition. [ABSTRACT FROM AUTHOR]

This article presents an application for educational purposes in the field of engineering graphics, which corrects the dihedral projections of the sections of a plane for a part by comparing the solution provided by the student with that obtained through 3D CAD modelling software. Said application is generated as a macro in CATIA (Computer-Aided Three-Dimensional Interactive Application), which is included as a tool in the 'Part Design' module. The code of this macro is written in the CATVBA language, utilizes the CATIA internal editor, and takes advantage of the capabilities offered by Visual Basic for Applications (VBA) in the design of Graphical User Interfaces (GUI). The operation of the macro consists of obtaining the section in the 3D CAD model, projecting it onto three dihedral projections of the part (elevation, plan, and profile), and calculating the visible and hidden lines by means of a numerical process based on dividing the lines into discrete sections. Likewise, to obtain numerical results, the section obtained in CATIA (reference section) is compared with the section provided by the student (section that needed to be corrected) by means of a spreadsheet (Microsoft Excel). The data of the coordinates of the points of the reference section are exported to said spreadsheet as is the data of the coordinates of the section that needed to be corrected, which is contained in a file with a dxf format (Drawing eXchange Format). From these data, by programming the appropriate formulae in the cells of the spreadsheet, the numerical values of the errors are obtained, thereby locating said errors in the dihedral projections of the section which needed to be corrected. Likewise, the application can be programmed to compare the central symmetry of both of the sections. [ABSTRACT FROM AUTHOR]

This article presents a useful application for university courses in Engineering Graphics, and for manufacturing processes based on developing sheet metal. From the basis of a three-dimensional surface, the application can generate its development, as well as its area and perimeter that could be used by a conventional numerical control machine (CNC) to cut the sheet. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 295–304, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20247 [ABSTRACT FROM AUTHOR]

This article shows an approach to the three-dimensional modelling of a sugarcane mill and its associated steam engine, designed by the Robey and Co. engineering company in 1869. In order to obtain the 3D CAD model of said invention, CATIA V5 R20 software has been employed. Various sources of starting material, from the basis of this research and found in the process of searching for relevant information, provide information on the main elements, operating conditions, and mechanism of the machine. Thanks to the three-dimensional geometric modelling carried out, it has been possible to explain, in detail, both its operation and the final assembly of the invention through the assemblies of its different subsets, thereby obtaining a virtual recreation that shows its operation. Likewise, a study has been carried out, from a mechanical engineering viewpoint, of the gear train that transmitted the movement, in order to ascertain the compression force exerted on the sugar cane. This research, related to industrial archaeology, therefore, enables the reader to understand a machine that constituted a milestone in the sugarcane industry, while paying tribute to the English engineer, Robert Robey. [ABSTRACT FROM AUTHOR]

This article introduces an innovative application of Visual Basic for Applications (VBA) (Visual Basic macro language) developed in CATIA (Computer-Aided Three-Dimensional Interactive Application), computer-aided manufacturing and engineering design software. Said application enables the three-dimensional (3D) representation and development to be obtained on a plane of the surfaces of cylindrical and conical elbows utilised to join two conduits, since CATIA lacks tools for the design of elements of metal fabrication. The application permits the geometric and dimensional parameters necessary for the creation and development of the analysed elbows to be introduced via a keyboard. Once these values have been entered and it has been verified that the design of the elbow is possible, then the application is programmed within the CATIA "Wireframe and Surface Design" module to obtain the 3D representation of said elbows, and the development of their surface is projected in the CATIA "Drafting" module. Consequently, the incorporation of this tool into CATIA software could increase technical-design productivity by eliminating certain intermediate operations, such as symmetry, and through improving the geometry training of less skilled users. [ABSTRACT FROM AUTHOR]