BALBINOT, Antenor, BARRETO, Deli Garcia Olle, BATTASTINI, Luciano, GAMA, Flavio Nogueira da & MENEGOTTO, Renato Gilberto Gama
Avenida Ipiranga 6681 CP 1429-90619.900-Porto Alegre-rs (BRAZIL) Telephone: (0055) (051) 320-3564-Fax: (0055) (051) 320-3623, PONTIFICIA UNIVERSIDADE CATOLICA DO RIO GRANDE DO SUL - PUCRS, Faculdade de Arquitetura e Urbanismo – FAUPUCRS, fau@music.pucrs.br
Abstract: Considering the existence of new technologies used in information and communication and the familiarity of the new generations, the Department of Graphical Expression of the College of Architecture of the Pontifical University Catholic of Rio Grande do Sul-FAUPUCRS- has developed a project of research with the objective of using these technologies to treat eventual difficulties of pupils in the of descriptive geometry. Using CAD software (AutoCAD) an interactive routine has been developed that contributes for a better agreement of 3D objects; this facilitating its representation in the design. This work, in time, will be placed on the Internet for free access for pupils. The routine consists of a screen divided into for spaces in which appears front view, top view, left-side view and isometric perspective of the projected elements. As important attribute of the program is the possibility to be visualized, on the screen straight lines, planes, surfaces and its interference only with the information of the coordinates (x,y,z) for the user. Bars of tools have been created for a better use of the program.
Keywords: geometry, Cad, Routine
The present work is a result of research of a small group of the FAU-PUCRS. It consists of a routine developed in the AutoCad. This software was chosen because that is the drawing program best known by the pupils of this college. This routine was idealized with the thought to approach it of the activity developed for the pupil the most possible. This activity consists of identifying orthographic projections of points, straight lines, plans and other surfaces. The determination of the projections of points involves the use of coordinates. In the next moment the pupil must establish a biunivocal relation between the projections and the represented geometric being. In a subsequent moment the pupil establishes relations between straight lines and surfaces , plans and surfaces and finally between surfaces.
In the figure 1, it appears the graphical screen of AutoCAD divided in four areas where area 1 represents the horizontal plane of projection, plane of the to top view. The area 2 represents the frontal plane of projection, plane of the front view and area O represents the profile plane, plane of the left-side view. The remaining area represents the tri-rectangle triehedron in isometric perspective. The representation is made in the first-angle projection, according brazilian norms.
Figure 1
In figure 2, as example, it appears a triangular pyramid, sectioned by a plan. The pyramid was generated using 3D FACE command of the AutoCAD and providing the vertices coordinates. Equally in generation of the plan (quadrilateral) the 3D SURFACE command was used providing the vertices coordinates . When the pupil, by digitation , provides coordinates of a point its projections appear simultaneously in the four areas and any modification made it reflects in all the areas. The same way used with the pyramid can be followed by the pupil with any surface. For in such way, they had been developed tutorials that they allow the pupil to project any surface as any plan, exactly not knowing the AutoCAD. The tutorial ones reflect developed problems in classroom antecipatedly. Such tutorials was tested in some groups and they had disclosed to an aid of great value for the so important representation and visualization in Descriptive Geometry.
Figure 2
In figure 3, the RENDER command of the AutoCAD was used, thus allowing the visualization of the intersection of the plan with the surface of the pyramid in all views and the isometric perspective.
Figure 3