Modeling a robot
Level: Beginner to intermediate
Introduction: 3D modeling is one of the most interesting parts of the CG, but it provides quite a challenge for a beginner to the 3D modeling. In this tutorial we will take you through various techniques involved in modeling an simple looking robot in Blender. This particular robot is called 'papero' and its a companion bot produced by 'NEC' Corporation Japan.
Please note that this article is not made for any commercial gains and neither is allowed to be distributed or used for commercial gains. It is not affiliated to NEC in any way. The NEC robot referenced here is purely for educational purpose only.
The best approach to learn from this tutorial is alos to consult the blender manual where ever you find it necessary, especially if you are very new to blender then learn about the various naming conventions like view-port, 'edit mode', vertex, 'transformer gizmo' etc. In this tutorial care has been taken to provide these features as the heading of the steps, so that if we say add a cube you can reference on how to add an object step learned previously. Reading it once is recommended for all new users to the 3D world of Blender even if you are not able to follow it properly.
First of all make a search on goggle for 'papero' or 'NEC robots' for reference images. Try to figure out how the model looks from different views. There are few different versións available but we are going to make a generic body. It would be helpful if you can get image1 from the net, if thats not possible it is alos provided in the sample blend file for this tutorial.
Modeling the head
Step 1. Adding a image to the view port: Start up Blender. First thing you need to do is delete the default cube. Right clik on it to select it, if its not already, then press [Del] and confirm deletion in the popup. Now we will add an reference image of the robot in the view port. Press [NumPad 1] for front view in the view-port, now go to 'View |Background Image...' menú of the view-port. In the popup clik on the 'folder' icon and navigate to the reference image, select it and press Enter.
Step 2. Adding primitives : Now we will start modeling, we will first start with modeling the face. Keep the mouse in the view-port and press [Spacebar] In the popup menú go to Add |Mesh | UVsphere. Again in the new popup reduce the number of vértices to 24 and again 24 in another popup then press OK to add the sphere.
Step 3. Working modes: Note that the sphere is added at the place where the insertion cursor(red white striped circle) is and the center of the circle is represented with a pink dot. Alos you will notice that the object added is in 'edit mode'. You can toggle the 'edit mode' to 'object mode' by pressing [Tab] key once. Do it now.
Step 4. Moving Objects: Now to position the sphere in 'object mode' to the head part as seen in the reference image in back. To do that, move your mouse over to blue arrowhead, clik and keep pressed the button and move the mouse upwards. The sphere object will move upwards, keep pressing [Ctrl] Key to make big grid jumps. Use [Shift] in combination for minor grid jumps. Position the sphere as seen in the image.
Step 5. Scaling Objects: To scale any object in 'edit mode' or 'object mode' you first have to select the object or its parts. Since the sphere is already selected. Press [S] key and any mouse movement towards the object center will result in scaling down of object and inversely any movement away from object center will result in scaling up of the size. Here scale up the size of sphere as shown in image following the reference in the back. Note again, you can compliment the scaling operation with [Ctrl] or [Shift] or combination of both for better control.
Step 6. Selecting vértices: Up to now you were working in 'object mode'. Keep selected the sphere and press [Tab] to get into the 'edit mode'. 'Edit mode' is the core of working on a 3dmodel, so learn and observe carefully. Now we will learn to select vértices. You can do various types of selection in blender. To select or deselect all vértices use [A] key to toggle. Press [A] til all vértices turn black(deselected). Now press [B] (box select) and move your mouse cursor to the top left part of the vértices in sphere clik and drag down so as to select the left part as shown in the image.
Step 7. Deleting vértices: Now we will delete the selected vértices. To do that, press either [Del] or [X] key and in the popup, select 'vértices'. As now you can see the selected vértices are all gone. We did that because the robot head is symmetric in appearance, so we need to just worque on one half and later mirror it to get the complete head. Now as you can see in the image, we have alos selected the ear part of the same sphere. Yes we will delete them too. Do it the same way as explained just now.
CREATING THE EYE PIECE
Step 8. Zooming in the view-port: To zoom in the view-port you can use 'scroll wheel' or [NumPad +] [NumPad -]. Now press [Z] key to toggle to shaded view mode from wire fame mode. Now as in the image, select the two vértices by keeping pressed [Shift] key and right clicking on the individual vértices, select as shown in the image and then delete the two vértices to create the eye hole for the robot head.
Step 9. Using Subsurface: Subsurface is the most important tool in 3d Mesh modeling. To enable Subsurface on the mesh, press [F9] and in the mesh tab in the buttons window (below the view-port) Clik the 'SubSurf' button, alos the optimal button and increase the divisions to 2, see image.
Step 10. Creating a face from vértices: Select the vértices as shown in the image10 and press [F] key once to make a face out of selected vértices. Now repeat it for other vértices on the hole as shown in the image11.
Step 11. Subdividing an edge: Select the two vértices which are inside the hole for the robot eye. Press [W] Key and select 'Subdivide', as soon as you select it the face gets divided into two faces. Image12. Repeat the steps with other newly created faces.
Step 12. Merging faces: Triangular vértices faces are bad for a smooth surface so we need to convert the two triangular faces to a single four vértices face. To do that select all four vértices of any of three vértices faces. Watch image 12 for example. Now go to 'Mesh |Faces |Convert triangles to quads' in the view-port menú. And the triangular face gets converted into a four sided face.
Step 13. Scaling the vértices: now select the vértices as shown in the image13 and scale them up a little bit so the shape of the eye hole looks like a circle. Here try to move the outer vértices of the eye in a straight line, use various methods of selection that you have learned earlier.
Step 14. Extruding the faces: Get in to 'Side view' by pressing [NumPad 3] and select all the vértices of the eye that form a circle. Press [E] to extrude the selected vértices and start moving the extrusion in the direction of green axis of the transformer gizmo as seen in the image 14 (a) and (b).
Step 15. Keep the last selection, now press [NumPad 1] to change bak to the front view. Here once more press [E] to extrude and immediately press [S] to scale down the extrusion a little. See image 15.
Duplicating the vértices: To make a copy of the selected vértices/faces you can press [Shift +D]. Continued from the last selection press [Shift +D] and immediately press [P] (to separate it from the mesh into another object) clik "selected" in the popup. Now you can press [Tab] to get out of the 'edit mode' to 'object mode'. Right clik to select the new circular mesh and press [Tab] to enter 'edit mode' for it.
Step 16. Now we need to create the tube like section for the eye. Select all the vértices [E] extrude them down a little (image 16a) Now get in to 'side view' [NumPad 3] and extrude the selected vértices towards green axis twice as seen in the image 16b.
Step 17. Welding the vértices: Welding or merging vértices gives us a closed face which we want for the bak of the eye piece to be like. Now again press [E] and immediately 'right click' to leave the transform state. Now press [Alt + M] in the popup select 'at cursor' and you can see the duplicate vértices get removed and they all form a face as seen in image 17.
Loop selection: Now we need to create a eye cover glass for the eye piece. select the second loop of vértices from the eye piece. Press [Alt + B] and hover your mouse over the second circular loop in the image 18. The active selection will show a blue loop forming on it as soon as it does left clik once to select the loop. Duplicate it and separate from this mesh. Get out of edit mode [Tab] now select the newly created mesh and press [Tab] to get into edit mode.
Step 18. Following the image 20 extrude once and scale it down (image 20a) Then extrude it again, immediately right click. Then press [Alt +M] to join the vértices and complete the face for the eye cover glass. Get out of 'edit mode'.
CREATING THE EAR & MIRRORING THE HEAD
You have noticed that many times we have duplicated a mesh part to start working on another part of the model. This is done for two reasons firstly the duplicated mesh we get fits closely to the par of the model where we picked it from and secondly it sabes a lot of time, if we made that part from scratch like scaling moving and positioning it close enough. In the coming part we are going to deal with it even more
Step 1. Inner Ear: Again we will use duplicating method to make the ear piece. First select the head mesh get into 'edit mode' do one extrusion to very small distance towards red axis (image 19b) and duplicate it by [Shift +D]. Now get out of 'edit mode' and select the newly created mesh. Again get into 'edit mode' [Tab] and do three extrusion in red axis as seen in the image 19c.
Finally create one more extrusion and scale it down a little. Create a duplicate[ Shift +D] from current selection and separate [P] it from the mesh.
Step 2. Outer ear part: Exit the edit mode and select the mesh just created. As seen in the image 20 extrude it three times and once more right clik and weld the selected vértices [Alt +M].
Step 3. Once again get out of the 'edit mode' and add a sphere of 16x16 ([Space Bar] 'Add |Mesh |UVsphere') in the middle of the ear as shown in the image 21. make sure that you position if right. Chek the position in 'front view' and 'side view' see Image 21.
Step 4. Mirroring a mesh: Now the head is almost complete. Since the head is completely symmetric, we can go ahead and mirror it to get a completed head mesh. To do that select the 'head mesh' and make sure that you are in the 'front view' now press [Tab] to get into the 'edit mode'. Press [A] key til all the vértices are selected. Now press [Shift +D] to duplicate the selected mesh. Immediately right clik to cancel any transformation. Now press [M] to bring up the mirror menú popup. here choose 'X Global'. You will see the selected mesh is mirrored.
Step 5. Merging the mirrored surfaces:. Now using the 'transformer gizmo' of the x axis (red) bring the two meshes closer so that the near edges are overlapping each other watch the image 23a for the highlighted part.
At this point you can zoom in and make sure that those edges are 'correctly overlapping each other.
Now deselect all other vértices and make a box selection [B] around the highlighted part as seen in image 32a.
Press F9 and go to the 'Mesh tools' buttons tab (image 24) and make sure the 'limit value is 0.001' and then clik 'Remove doubles' button and you should get 'Removed 24' in the popup.
Now get out of the 'edit mode' and as soon as you get out of the edit mode you might see a blak line in the middle of the head mesh as seen in image 23b. Again get in to 'edit mode' select all vértices and press [Ctrl + N] (calculate normals). Now the mesh will look smooth and you have created the head of the robot.
Step 6: Creating the rest of the head parts. Now following the procedure of duplicating and mirroring go ahead and do the same for the 'eye piece' (image 25a) eye glass' and the 'ear ball'. After you have done that the final model should look some thing like in the image25b.
CREATING THE Upper & Lower body
Step 1. Make sure you are in 'Object mode'. Go to 'top view' [NumPad 7} and add a UVsphere [Space bar] 'Add |Mesh | Circle ' of 24 vértices (image 26). Get out of the 'edit mode' and change the view mode to 'side view' [NumPad 3]. First position the circle just below the 'ear part'.
Step 2. Rotating the objects: Press [R] key to rotate the circle as shown in the image 27a. Get into 'edit mode' and extrude once downwards on the Z axis (blue) and scale it as shown in the image 27b. Following the image extrude once more.
Step 3. Extrude once more following the image 28a. Now we need to make out the body design as seen in the reference images. To do that get in to the 'front view' [NumPad 1] and box [B] select the vértices as shown in the image. [G] grab the vértices and immediately press [Z] and pull them down as shown in the image 28b and 29a.
Step 4. Adding a loop of vértices: At this point we need to extrude vértices once and then scale them down so that we get a smooth bend edge for the body. But you will notice that the body looks a bit pulpy so we will add a new loop of vértices just near the bottom part (image 29b) to make it look like a solid surface with defined edges. To add a edge loop press [Ctrl + R] the cursor will now change in to a blue lop line and will follow the position of the mouse, bring it down and near to the bottom part as seen in image 29b and clik to add the loop.
Step 5. Lower body: Make a duplicate [Shift +D] of the same selection and separate it from the mesh. We will use it to make the lower body. Get out of the 'edit mode'[Tab] and select the newly created mesh and again get into 'edit mode' [Tab]. Now extrude once and scale it a little. Again extrude and bring the extrusion down a little.
Extrude and bring it down as seen in image and here move the vértices in the same line. Now extrude twice following the image 30a and weld[Alt +M] the last extrusion.
Step 6. Get in to the 'side view' and scale the lower part of the 'upper body' and upper part of the 'lower body' as shown in image31a. Get out of 'edit mode' completely and add a plane [Add |Mesh |plane], position it near the side bottom of the robot body, watch image 31b for reference. press [F9] for editing buttons and enable 'SubSurf' button. The mesh will turn roundish.
Step 7. Keep the view in 'side view' [NumPad 3] Extrude the side of plane(two vértices) two times and move the vértices to look like as in the image 32.
Step 8. Change the view to 'front view' [NumPad 1]. and extrude the plane three times outwards (red axis). and manipulate the vértices to as they look in the image33a image33b.
Step 9. After the robot 'shoe' has been done select all the vértices of the show and issue [Shift +D] move the selection to other side of the robot and after position it mirror [M] it in X axis. See image 34.
Adding left over details
Step 10. Changing the selection modes: The basic model is just about complete, we forgot to add the little bump in the middle of head. Now select the head mesh and get into 'edit mode' Now we need to use the selection method as face as it will provide for easier selection. Press [Ctrl + Tab] and in the popup select the 'face selection' the view will change a bit as shown in the image. Now you can start selection the faces by right clicking on them, here you will need a group of faces to be selected so keep pressed the [Shift] key.
Step 11. Extruding faces: Change the view to side. Extrude the faces upwards(blue axis) once. Now we need to rotate the selected faces only on x axis so we will press [R] and immediately press [X] and move mouse to rotate. Rotate the selected faces so that they look like as in the image.
Step 12. Change view to front. Now change the selection mode[Ctrl +Tab] to vértices. And select the side vértices (three each side) as shown in image37a. Following the background image in the view-port move them down (z axis).
See the outcome of it in the 'shaded' [Z] mode.
This wraps up the modeling tutorial. There are various smaller details left for the robot, they are left as an exercise for the reader. You can use use the methods provided here to create them, like the speakers in the front part of body and the tires of the robot. Make sure to read the other tutorial on texturing the robot in the learning section.
Gaurav Naw ani