Spring 2011 Workshop ESSENTIALS OF 3D MODELING IN RHINOCEROS February 10 th 2011 S.R. Crown Hall Lower Core Computer Lab

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1 [1] Open Rhinoceros. PART 1 INTRODUCTION [4] Click and hold on the Boundary Lines in where they form a crossing and Drag from TOP RIGHT to BOTTOM LEFT to enable only the PERSPECTIVE VIEW. [2] When the First Screen appears asking for File Units Choose the template for Feet. [5] There are two windows we will primarily be referencing. Object Properties and the Layer Manger. Click on each button to activate the windows. [3] You will see Four Layouts on the Screen. This is our Default Workspace.

2 [6] We need to define the layers that we will primarily use. This is achieved through the Layer Manager. In order to change the layer name, double click the layer name itself and it queries the dialog box allowing you to change the name. [8] There are some cases when using the pull-down menu is easier than typing a command. You can hover over each one to see what is available to us for modeling. You can also change the color by clicking on the color box next to each layer name. To activate a layer, double click in the blank white space near the layer name. [9] Save the file to the desktop by going to file save as. You will then be prompted to name the file and location. Call the file Rhino Part 01. To create a new layer, click the button in the top left of the layer manger that looks like a blank page. [7] You execute actions within Rhino the same way autocad utilizes a command line. At the top of your screen type the letter R and wait for the dialog box to drop down. This is the list of every command that exists beginning with the letter R. Essentially if you do not know the exact command for what you are trying to do, Rhino allows you to explore the options helping you pinpoint the exact command to execute.

3 PART II POLYGONAL MODELING [1] Within our newly named file make sure only the perspective view is showing. Type RECT to draw rectangle. [4] We will be making a square at 24 by 24 follow the instructions in the command line and enter 24 for both sides of the rectangle. You have to press ENTER after each length input. [2] Upon pressing ENTER we are allowed a few options before proceeding to the modeling space. We are going to draw a rectangle from its center point. Make sure the text in the command line for CENTER is active. This is done by clicking the word CENTER. [5] We need to be able to manipulate each line on its own. With the rectangle selected, type EXPLODE to make four individual lines. [3] Type enter to engage the rectangle command. You will be asked to define the start point for the center of the rectangle. Input 0,0,0.

4 [6] We need to divide each line (known as a curve in Rhino) into segments in order to develop a wireframe for our hypar surface. Select all the lines and type DIVIDE into the command line. You are prompted to enter in the number of segments. Enter twelve to create intervals at 2 apart on the line (i.e. 24 / 12 = 2 ). [8] Make sure point snap is turned on. Type LI to draw a line. Begin making 2d grid lines. Make sure these lines are on a different layer than the perimeter lines. If you are successful you will have points at each division along each line of the rectangle. [7] You can change the layer of each object by toggling the object properties and changing the layer the points are designated. place the points on a new layer called points. And the lines on a new layer called perimeter base. [9] Type COPY to copy this new line to each point in the Y direction.

5 [10] On a new layer, Draw a new line as shown in the picture below. This will begin creating the other grid lines in the X direction. [12] You will be given a dialog box that lets you manipulate the distance and number of items. enable distance between items and make it 2.0 feet. [13] This procedure makes two extra lines in our grid. Delete the extra lines. One will be hidden underneath the outer red line. [11] We are going to Array this line along a path. Type ARRAYCRV to toggle the commands for this procedure. Select the line First. Second, select the path curve. The path curve will be the red line oriented in the X direction. [14] In order to toggle different views in our display, right click where it says PERSPECTIVE in the top left of the viewport. Pull down the menu to SET VIEW. Then select the TOP view in order to double check our work.

6 [15] You will now see a square subdivided into 2 foot intervals. [18] When asked by the command line, select a line that has the blue color. Press ENTER. With the lines selected type GROUP in the command line to group these objects. [16] Return to the PERPSECTIVE view. [19] Do the same for the purple lines in the opposite direction. After these two sets are group select each of them and type HIDE. In order to see the lines again type SHOW. For now, however, we need them hidden. [17] We want to GROUP the lines that are similar. To do so type SELCOLOR to select objects by their color. You could also select by layer using SELLAYER.

7 [20] In order to draw the hypar surface we will define its wireframe. This is done through orthographic projection. First type LINE. Before pressing ENTER constrain the line to the z-axis. In the command line select Vertical or press the letter V and hit ENTER to constrain the line. Make this line 12 tall. [22] Draw lines from the lower corners to the top of each vertical line creating the basic outline of our hypar surface. You can use the MIRROR command here as well [21] We can use the MIRROR command to copy this line to the opposite corner. Type MIR for mirror and select the adjacent corner point. Then drag a mirror axis to the opposite corner (i.e. 45 degrees). This will copy the new line to the opposite corner. [23] Using the vertical constraint on the LINE command, draw vertical lines along the right most side at each point of the red perimeter line. You can draw one and use the COPY or ARRAYCRV command to make several lines of the same height.

8 [24] In order to trim these lines to size we use the TRIM command. [25] Type POINT and place a point at each intersection of the pitched line and the vertical lines. First you will need to make sure in the command line that ApparentIntersections is toggled to NO. Next select the cutting object which will be the pitched perimeter line defining a side of the hypar surface. Press ENTER. Trim away the overhanging ends of each line. [26] Select these new lines and points. Then type GROUP to associate them together.

9 [27] Use the MIRROR command to place this grouping onto all four sides of our square. [29] Now we begin to build the wireframe for our hypar surface. Connect points with lines that are across from one another. Essentially we will be building a curved surface from the manipulation of straight lines. Also known as a version of POLYGONAL MODELING. [30] After the blue set of lines is created hide the side vertical lines that are blue. This will make drawing in the opposite direction easier to read. [28] Make sure each parallel set is on a different layer. We will be using the colors to guide the construction of our wireframe for the hypar surface.

10 [31] Follow the procedures in 29 and 30 to complete the other side of the wireframe (purple lines). [33] Using SELCOLOR and HIDE command, hide all but the lines for our hypar surface wireframe. [32] You can rotate the view if you find that you cannot see the points you will need to connect. The ROTATE VIEW tool is at the top toolbar. [34] Now that we have all the data we need to create a surface. We need to make a record of it in case we need to go back and edit it in the future. Use the COPY command to create the same wireframe off to the side for further manipulation.

11 PART III NURBS MODELING [1] Type UNGROUP to ungroup the lines we previously grouped. We will need them to create the surface. We will use our wireframe to define the boundaries of our hypar surface. This is achieved by using curve network under the surface menu or type NETWORKSRF. [2] This procedure is highly complex and can be done incorrectly if you select the lines out of sequence. 1. Select the perimeter lines first in succession (lavender) 2. Select the interior lines next (purple) in order one after the other. 3. Select the next set of interior lines in order (blue) 4. Press ENTER. If this is done correctly done you will see four black circles indicating so with a dialog box for further control.

12 [3] Press ENTER. You will see what looks like more wireframe lines added to our drawing. However, this is really our surface. [5] We can also change how the ISOCURVE lines are displayed and how many. This is useful if working backwards from a surface back to a wireframe. In the object properties dialog box you can toggle these lines off and on and increase or decrease their density. [4] We can control the way this surface is displayed by right clicking where it says Perspective in the top left of the viewport. We want to use the SHADED view instead of the wireframe view [6] Turn off ISOCURVES.

13 [7] We are ready to create the framing members of our hypar surface. To do so we will use the PIPE command. [8] Select all the outer edge perimeter lines together and type JOIN. This will join the liens together into one connected polyline. Type PIPE. Select one perimeter line. You will be prompted to enter a starting radius and an ending radius. enter 4 for both. You can toggle diameter by clicking in the command box on the word DIAMETER to create a tube based on diameter entries. [9] Redo the PIPE command for this polyline. Zoom into the corner condition to see how the program handles this edge detail. WE now have a pipe defined by our perimeter line. Instead of trimming and joining at the corner intersections it is easier to join these lines first then re use the pipe command.

14 [10] Make a new layer for the interior members. Redo the pipe command for each individual member. PART IV VISUALIZATIONS AND EXPORTING [1] We now have a completed model of our hypar structure. We can make renderings and 2d drawings directly in RHINO. To assign materials to layers we need the layer manager box open. Click on the circle next to the layer you placed your hypar surface on. This will bring up a materials dialog box. In the larger box at the top make sure BASIC is checked. Here we can change the opacity, colors, glossiness etc. of any object on the layer selected. Select a color for the surface and change its transparency to 65 percent. This will simulate generally the material of glass. [2] Under the RENDER file menu scroll down to RENDER PROPERTIES.

15 [3] We want the background image to be WHITE. Under BACKGROUND, select the gray rectangle to toggle the color menu. Select White for the background color. [5] File- Save AS- and save to DESKTOP as a.tif file The tif file type stores alpha channel data for later manipulation in photoshop. [4] Under the RENDER file menu, scroll down to RENDER. Click on it to RENDER the image. [6] Position a view in the perspective viewport to make into a 2 dimensional vector based drawing. Select the objects (all pipes and surface) Type MAKE2D

16 [7] You will see a dialog box that asks you what to draw. Check the box for 4VIEW USA. U can choose on your own if you would like to see the hidden objects in the drawing depending on use. For this however we do not need to see them. [10] Select these drawings and go to FILE EXPORT SELECTED. We will be able to export to AUTOCAD to control line weights, scaling, and plotting. [8] Press OK and let the computer run through the drawings. [9] Change the perspective view to a top view and you will see your 2D drawings. [11] Repeat step 21 to export to different software. For use in 3dsMAX save as an IGES file. This will retain the NURBS data without meshing the surface. IT will also retain vector data and edit ability.

17 PART V SOLID MODELING [1] Open a NEW Rhino file defaulted to INCHES [2] Create 3 new layers. POINTS, CURVES, and GEOMTERY [5] Enter the BASE POINT at 0,0,0 [6] We would like to toggle the Diameter instead of the radius. To do so click on the word Diameter in the Command Window. [3] Set the viewport to a perspective viewport and make only the PERSPECTIVE VIEW active. [7] Enter the DIAMETER to be 1 inch (1 ) [4] In the MENU BAR go to SOLID TRUNCATED CONE. [8] Enter the HEIGHT of the CONE to be at ½ (.5 )

18 [9] Enter the DIAMETER at the top of the CONE to be 1 3/8 (1.375 ) [12] Right click on the PERSEPCTIVE MENU at the top left of the viewport. Scroll down to toggle the GHOSTED DISPLAY. [10] Toggle the Object Properties. For the new TRUNCATED CONE. [13] Make sure the Center snap is on Located at the bottom of the screen. Browne to the Menu Bar. Go to SOLID CYLINDER. When the dialog enters the command line check the CONSTRAINT FOR VERTICAL. [11] Click on the button that says DETAILS. This will toggle the text data associated with the object in question. We are looking to make sure it a CLOSED object.

19 [14] Select the center top point of the TRUNCATED CONE for the base point of the CYLINDER. With the QUAD and END POINT Snap on. Pull the circle radius out until it snap to the outer edge of the top part of the TRUNCATED CONE. [16] Browse to the Menu Bar. Pull down SOLID UNION. This will make these two objects one solid object. [15] Enter 7/8 (.875 ) for the HEIGHT of the Cylinder. [17] Double check that it is indeed a closed object by toggling the object Properties. Click DETAILS. Check for CLOSED OBJECT.

20 [18] Make another TRUNCATED CONE. This one will have the lower base at the top of the CYLINDER and at the same DIAMETER. Make the Height of this Cone at ½ (.5 ) and its TOP DIAMETER at 1 ¾ (1.75 ). [19] Next Create another CYLINDER on top of this TRUNCATED CONE. Its Diameter will equal the top base of the Truncated Cone at 1 ¾ (1.75 ). Make sure Vertical Constraint is Checked. Height will be 2.

21 [20] Go to the MENU bar. SOLID SPHERE- CENTER,RADIUS. This will create a sphere from its center at a specified radius. [21] UNION all the OBJECTS together. Make sure the Object is a closed object. This Sphere s base point will be at the CENTER of the TOP BASE of the last Cylinder made. Its Radius will match the Radius of the TOP BASE of the CYLINDER.

22 [22] We are now going to model the inside space of the fork fitting. Imagine that we are digitally modeling the negative space of the inside the fork fitting. Make a cylinder off to side. Begin by making a CYLINDER off to the side at 3,0,0 for its base point. Constrain this to VERTICAL [23] Next Model a TRUNCATED CONE with its base point at the top of the CYLINDER. Height of the TRUNCATED CONE is set to ½ (.5 ) and the DIAMETER at the top is set to ¾ (.75 ). The DIAMETER of the CYLINDER should be set to ¼ (.25 ). The HEIGHT should be set to 1 3/8 (1.375 ).

23 [24] To finish the inside space we need to make one last cylinder. The CYLINDER s base point and Diameter will start at the top of the Truncated Cone. We will use POLAR TRACKING to constrain its height to the massing of the fork fitting. [25] UNION this object into one CLOSED OBJECT Check to make sure this is so.

24 [26] We need to make a copy of this into the CENTER of our mass of the fork fitting. Type COPY. Select the bottom center point of the new mass. Copy this object to 0,0,0. The new object is now nested inside the massing of the fork fitting. [27] The inside Mass can now be combined to make a cutout for the main fork fitting mass. Go to the MENU bar, pull down the SOLID menu and scroll down to DIFFERENCE. HIDE the original object set at 3,0,0. HIDE or DELETE the original inside massing. [28] Select the Fork Fitting Massing First. Press ENTER.

25 [29] Select the interior object next and press ENTER. [31] Set the PERSPECTIVE VIEW to a FRONT VIEW. [30] Rotate the view to check if the inside of the fork fitting massing was removed. Also check to make sure it is a CLOSED OBJECT. [32] Draw a Line from the center of the inside top most TRUNCATED CONE.

26 [33] Drag this line beyond the boundary of the massing. [35] Select the line and then position the Mouse to either side of the original line and press ENTER. Repeat for the other side. [36] Connect the two new lines at the top with a new line. [34] We can COPY this line, or for more control type OFFSET. Specify the offset distance to be ¼ (.25 ). [37] Draw a CIRCLE of Diameter ½ (.5 ) with its CENTER point and the starting point of the first line.

27 [38] MOVE (type M) this circle up ½ (.5 ). this will TRIM the lines that overhang and the top portion of the circle. [39] DELETE the Center line. Use SELCOLOR to select all the red lines. Type JOIN to join these lines into one Polyline.

28 [40] Set the viewport to the top view Select the newly formed Polyline and move it up beyond the boundaries of the mass. Switch the view back to PERSPECTIVE. [41] File Menu SOLID EXTRUDE PLANAR CURVE STRAIGHT. Select the Polyline. Extrude this curve beyond the boundaries of the mass.

29 [42] Use the Boolean Difference to Bore out the area that will seat a plate for attachment in real life. [43] DELETE the Polyline File Menu SOLID DIFFERENCE Select the Mass First Then select the Extruded Polyline mass. [44] Go to the TOP VIEW Draw a LINE down the center of the fork fitting mass so that it extends beyond the boundaries of the top and bottom.

30 [45] MOVE or OFFSET this line ¾ (.75 ) to both sides of the mass. If you use the MOVE command you will have to MIRROR this line about the Y-axis. [46] Set the View to PERSPECTIVE. Got to File Menu SURFACE EXTRUDE CURVE STRAIGHT. We will be using these planes to CUT away the flat portions of our fork fitting mass.

31 [47] Go to the FRONT VIEW. Type TRIM. Select the PLANES as CUTTING OBJECTS. Press ENTER. Select the outer boundaries as the objects to trim away. [48] Go back to the PERSPECTIVE VIEW You may have an issue with the CPLANE which is our coordinate system staying at the FRONT VIEW. To change back to normal, go to File Menu VIEW SET CPLANE WORLD TOP. This will re-orient our CPLANE to the correct mode. [49] To fill the gaps in the mass. Goto file menu SOLID CAP PLANAR HOLES.

32 [50] Toggle a SHADED View and CHECK that the object is closed. [51] We now have a completed version of the Fork Fitting. A extra step is to duplicate the silhouette of the object for rendering and visual purposes. Got File menu CURVE CURVE FROM OBJECTS - SILHOUETTE This will give curves around the object boundaries. Group these lines.

33 [52] Toggle the RENDER PROPERTIES. [53] THIS IS YOUR FINAL IMAGE. File Menu RENDER RENDER PROPERTIES Check that Render CURVES is on and everything else is off. APPLY and CLOSE this window. RENDER the IMAGE.