Computer Aided Drafting: Creating 3D Models and Scenes in T317 using Braukmann's Method, Study notes of Biotechnology

Download Computer Aided Drafting: Creating 3D Models and Scenes in T317 using Braukmann's Method and more Study notes Biotechnology in PDF only on Docsity! T317, Computer Aided Drafting, Braukmann, 2/21/02 Page 1 3D Surfaces 3DFACE Go around CW or CCW, (not like solid) Will define a surface or series of adjacent surfaces. Three or four points will define one 3D polygon face. To hide the lines between the faces: 3DFACE, when it asks for the "first point" of the line you want to make invisible, Type I <ret>, then specify the next point or location <ret>. Repeat for subsequent points. Quality First SETVAR <ret> then SURFTAB1 and SURFTAB2 to set the number of divisions the area will be divided into. RULESURF 2 lines define a surface; will be ruled from the first to the second. Number of lines is set by Surftb1.When you select the lines, the end of each line closest to the "snap point" will be where rule #1 is drawn. TABSURF Choose two lines. The first will be the "starting line" and the second will be the vector to be copied at intervals along that line. The number of vectors will equal Surftb1. EDGSURF 4 lines define a surface; will be ruled in both directions, & will hide other entities. ` The number of lines in each direction will be set by Sruftb1 & 2 REVSURF Like Revolve in Mac3D. Uses any line as an axis. Creates surface model. Regions Creates a surface with multiple holes in it. Can be extruded. Simply asks you to select objects. Should use polylines for the complex shapes. Must be closed objects and not ones that cross over themselves like a figure 8. Strategies 1) Draw 3D basic layout and construction lines on their own layer. 2) Look for lines that you can copy. Any two lines will give you enough for a new UCS. Look for surfaces that you can copy. Don’t redo any if you don’t have to. 3) Make a hidden layer for the surfaces. Put them there as you make each one to get it out of your selection area. 4) Use polylines ahead of time, where you will need them. UCS User Coordinate System World The original. X is across, Y is to the top of the screen. New Zaxis At a new origin point with an option on direction of Z axis You can draw from a viewpoint looking down an axis (like drawing a circle around the axis of the fuselage of an airplane) 3point Three points define a plane. pick, origin, X direction, general Y direction OBject Face View Aligns with the current VPOINT, (bring in a border!) X/Y/Z Rotates the existing UCS around the specified axis. Point the positive axis toward you and rotate CCW. Move Slides it to a new location along the Z axis. Orthographic Uses one of six presets. Apply (?) Previous, Restore, Save, Delete allow you to save & reuse them Going to the UCS to draw: View > 3D Views > Plan View > Current UCS In 3D the grids are not always what/where you think, snapped lines will be created only in UCS T317, Computer Aided Drafting, Braukmann, 2/21/02 Page 2 Aircraft Demos 1) Make certain you have all the required details in place before you start adding extra details. You will be graded on the required details. 2) This will take some planning. You will need a number of logical layers. You will need to name and save UCSs 3) Demos Draw a airplane wing (polyline, tabsurf1=30, rulesurf) Create a fuselage centerline (UCS New, 3P on wing bottom, line) Mirror the wing (Plan view, mirror over centerline) Go to the front and draw a circle for the fuselage (first draw a line sideways from center line) Extrude the fuselage back through the wings (rulesurf) Create the canopy (a good demo of USC changing) Get the slanted lines with the arc between and RULESURF between front/back Front: RULESURF between arc and line at base. Shading for viewing Use View > Shade > Gouraud and view with the 3D viewpoint tool Discuss Options Rotate wing after mirroring to get the right angle Explain how to create a 3DPOLYline Can spline, but not fit. No width options. Great for Lofting operations, creating a path to rotate in revsurf. Surfaces can be copied to the back of objects.