RHINO; AN INTRODUCTION + FAKING TRABECULAE; EndOfLine.info;

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1 RHINO; AN INTRODUCTION + FAKING TRABECULAE; EndOfLine.info; Rhinoceros is a relatively simple program with an AUTOCAD based interface. The disadvantage of this type of interface is a series of terms need to be committed to memory to use the software effectively. The advantage is that once a series of basic commands have been committed to memory the process of using the software increases exponentially. Setting Up; After you have opened Rhinoceros 5 you should see a screen with a series of buttons and tabs. If your Rhinoceros window does not have this then click on Toolbar Layout in the Tools dropdown menu. The Rhino Options window will open with the Toolbars tab selected. Click the Restore Defaults and then press OK on the pop up window. The software will then warn you that you must restart rhino for the process to be complete. After restarting, your window should look very similar to the image below. Interface; Upon opening the interface you will see that it initially shares but has differences to that of AutoCAD s interface. It has a command line and a series of technical modes down the bottom. 1. The Menu Bar. This is a menu bar identical to that of most other pieces of software containing File, Edit and View dropdown menus, however every single rhino command is stored in the following geometry based drop downs of Curve, Surfaces, Solid and Mesh dropdown menus. All the dimensioning tools are held within the Dimension dropdown menu, and the same logic applies to the other tabs. 2. The Command Line. This is where you can directly type commands into Rhinoceros. For example typing Line starts drawing a line t EndOfLine.info p 1

2 3. The Shelf. This is very similar to the shelf in Maya, it has a series of commands that the developers consider useful, however this can be edited to put the commands you find yourself using a lot in there. 4. The Main Menu. Very similar to the shelf, however it has been pulled out as it deals with modes of constructing geometry. is fairly good for contrasting against most of the preset information in rhino, expand the Appearance menu within the Rhino Options dialog box selecting color and change the background or type GradientView in the command line. 5. Layers/Properties/Display/Help Menus. This is where the properties such as your layers, what layer an object is on, what color it is and a few other pieces of information are held. 6. Snaps and other cool stuff. This is where you can change how the mouse and history responds to an object. Setting Up; Before any actual modelling can be done, you should check that your file is in the right units, if you look down at the bottom of the screen it will express the files units settings at the bottom left hand corner next to the current mouse position and before The current layer. If the units are wrong for the work you are doing, right click the units and then left click the Unit Settings from the dropdown menu. This will again open up the Rhino Options window, but is now referring to the specific file you have open. Within the window you can change the model units and the tolerances (tolerances are very important in dealing with fabrication problems with NURBS geometry and should be considered for all issues surrounding 3d printing.) By double clicking on the text that says the viewports name (for example Perspective ) you can make it full screen. and click on Osnap. Camera Guide; The camera in Rhino responds to the following commands: Scrolling the middle mouse button zooms in and out. Right mouse button pans in 2D projections and rotates in 3D projections. Shift + Right mouse button pans in 3D projections. The last thing to consider when setting up a file in Rhinoceros is the files Background Colour. You can either come to terms with the neutral gray colour as it t EndOfLine.info p 2

3 FAKING TRABECULAE; this before you press enter to complete the command: Modelling requires planning, there needs to be more than a clear image of what you want in your head, you need to be able break it down into a series of steps that are achievable through computational methods. Consider Supermanoeuvre s Trabeculae, although it is done through computational methods the result can be copied manually through putting a number of rhino commands together. [ 1. Let s set this up as a 50m by 25m. Also let us assume that a floor is 3.5m. So let s draw a 50m x 25m x 3.5m box by typing box in the command line. The command line will now prompt you for a starting position, you could choose any point in xyz space, but we will choose the origin by typing 0 or 0,0,0. It will then prompt you for the dimensions of the box one at a time. Type in the dimensions taking note of the scale of your file (50m in millimeters is 50000mm). 3. Let s lock the tower on another layer so we can start working on looking at generating the cuts. Select the tower by clicking on it. Go to the Layers Panel - The icon is the one that looks like a cake and right click on Layer 01 and select Change Object Layer from the dropdown menu. You will notice the tower turns red. Click the padlock next to Layer 01 in the Layers Panel to lock the tower. 2. Let us scale the tower up vertically the number of floors we want, in this case 30. Make sure the End snap is on in the Osnap menu, before typing Scale1D in the command line. Rhino s command line will then prompt you for an origin point which in this case is one of the corners of the box. It will now prompt you for a Scale factor or a reference point, in this case we want to set the scale factor to the number of floors, 30. Rhino will now prompt you for a scale direction while it deforms the box; snap to the point directly above the corner of the box you selected originally. Your screen should look something like 4. Now we need to start making some curves t EndOfLine.info p 3

4 going through the tower to use as a rail to subtract material from the mass. Make sure that your rendering is set to Ghosted from the Viewport dropdown menu and draw a number of curves that have their ends outside the mass of the tower, by typing Curve in the command line and clicking to place control points. 6. With the curves selected type PointsOn in the command line, you will notice that each curve has 5 points. Select several points and type Move [DO NOT DRAG!] You will notice that the move command has a series of options, in this case we want to move things vertically, so click on vertical or type v. Now you can move the points up within the solid by clicking on a starting position and then clicking again on an ending position. You should have something that looks like this: 5. Marque across the curves making sure that you either: a. Drag from the left making sure that all the curves are entirely within the marque; or b. Drag from the right making sure that all the curves have a portion within the marque. Then type Rebuild in the command line leaving the Point Count at 5 and changing the Degree to 2 and press OK. Continue moving the points up through the solid until you are happy with their positions. In the end we are looking for something like this: t EndOfLine.info p 4

5 geometry. Draw a line along the x-axis by typing Line into the command line. Type 0 to set the start at the origin and hold down the shift key to lock the line to the x-axis and then click to end the line. Now draw a curve to the side of the line and type revolve in the command line. Select the curve as the object to revolve, select the start of the line as the start of the revolution axis and select the end of the line as the end of the revolution axis. Set the angle to 360 and press enter you should have an object that joins up onto itself like so: 9. Select the surface just created and type Cap to turn it into a polysurface that is completely closed. 7. Now as before select the curves and lock them onto Layer 02 and hide both Layer 01 and Layer 02 by turning the lightbulb off. 8. The screen should now be empty of any 10. Unlock and Turn Layer 02 to visible. Now type Flow into the command line. You will be prompted to select an object in this case the polysurface then a base curve in this case the line. One of the options in the command line will say Stretch make sure that this equals Yes If it equals No click on it OR type s into the command line. After doing every curve select one of the tubes and select one touching it and type Boolean Union until all of them are joined together. [This needs to be done one by one!] You should have something hideous like this: t EndOfLine.info p 5

6 13. Here we need to mesh the tower box and solve the intersections between the trabeculae. So select the box and type Mesh then add the meshed box onto the Default layer and turn off Layer 01. Now use the command Mesh Trim to trim away the excess by selecting the box as the cutting object and the trabeculae as the object to be cut. [Make sure you select the bits you DON T want.] Deleting the Mesh Box leaves you with something like this: 11. Now type Mesh in the command line and put the original polysurface on Layer 03 and hide it. 12. Selecting the Mesh Version of the form, type Smooth into the command line. Now press spacebar untill you are satisfied with the smoothing. You should end up with something like, this may take some number of commands. 14. Select the meshes and type OffsetMesh into the command line. A dialog box will open up in which you can give the mesh a thickness, in this instance let s put 0.1m on each side. 15. Now turn on the box layer Layer 01 and type Contour in the command line. Rhino will prompt you to select objects, which in this case is the un-offset mesh AND the Box. Rhino will now prompt you for the base point, choose a point at the bottom of the tower, then it will prompt for a direction, choose a point directly above the base point you just selected. It will finally ask for a distance, in this case it is 3.5m. t EndOfLine.info p 6

7 16. Move the mesh to Layer 05 and hide that layer. Select the curves and type Join in the command line. Level by level, select all the curves on that level and type Curve Boolean. You will be prompted to select the areas you want to KEEP, which in this scenario is the floor plate that hasn t been eaten away by the mesh. Make sure in the command prompt, that delete input is set to all. Then with the new curves selected type PlanarSrf into the command line to turn it into a surface. 17. Click the new layer icon and make a new layer. Then type SelCrv to select all the visable curves and add them to the new layer Layer 06. t EndOfLine.info p 7

8 18. Offset the box inwards by scaling it 1D in the x direction by (50-0.5)m then using the Move command to move it in that direction in 0.25m, do the same in y for (25-0.5) m, moving it 0.25m as well. view in which it was drawn, in this case, the perspective view. This allows you to quickly look through a piece of geometry to find the section or plan you would like to cut. 19. Select the Meshes on Layer 04 and type MeshToNURB in the command line. This may take a while but the mesh will be copied as a polysurface. Put the mesh onto a new Layer, Layer 07 leaving the polysurface version of it on Layer 04. Type Split to delete the excess components of the box leaving you with something like the image to the below. 20. Finally select the floor plates and type ExtrudeSrf into the command line. Extrude them a distance of 0.3 m making sure that solid is set to Yes. Drawing and Exporting; Now double click on the perspective title to return to 4 view. You will notice that it is only active in the perspective view, if you want to turn the clipping plane on and off in particular views, as long as the clipping plane is selected you will have access to a Clipping Plane Tab in the Object Properties menu. You may tick and un-tick the views you want the plane to be active in. Rhino has a series of Mechanisms to get drawings of 3D objects out quickly. This section will quickly look at a couple of production based Rhino commands. Although Rhino can do everything that autocad can do, that will be an exercise left to the reader. The two most important commands in Rhino for the production of orthographic drawings are ClippingPlane and Make2D. Type ClippingPlane into the command line and you will then be prompted to draw a rectangle. Note that you can draw a rectangle on the construction plane, which is by default set to the top view for plans OR you can click on Vertical or type v into the command line to take a section. You will notice that the rectangle clips the geometry in the t EndOfLine.info p 8

9 Now, select your objects with the clipping plane and type Make2D, you will be presented with the following dialog box: Exporting in Rhino is the same as within any other piece of software for the most part, except you can export EVERY object or just SELECTED objects. Once you have selected the objects you wish to export you will be shown a save file dialog box. Make sure Maintain Source Layers is ticked and press OK. In the Top View you will notice you will be rewarded with a line drawing of all the selected NURBS objects from the view that was selected when you wrote the command. The command DOES NOT make drawings of mesh objects. Further, you will notice that the drawing respects the layers that the objects where on. One of Rhino s strengths is its compatibility. However there are a few that are more useful then others:.3dm - this is useful for backwards compatibility (There is an error in Rhino 4 with the way the Trim command works that can be a time saver).ai - this is useful for exporting drawings to Illustrator..IGES - this is useful for exporting files to other NURBS suites. [Maya].OBJ - this is useful for exporting files to other MESH suites. [Maya, 3DS Max].STL - this is useful for exporting files for 3D printing..dwg - this is useful for exporting files to autocad.sat - this is useful and extremely annoying to export Rhino Geometry into Revit..TXT - this is useful when trying to rebuild a file through algorithmic methods, such as Grasshopper and MEL. t EndOfLine.info p 9

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