Modellers – Weeks 5 & 6

We completed our dioramas with materials and lights and rendered the final images. Some people chose their own colours and some used a palette generator (see: https://coolors.co/bf4e30-c6ccb2-093824-e5eafa-78fecf) to choose a complimentary set of colours to provide a harmonious look for our scene.

We used the Cycles rendered and turned on the denoising options, which automatically remove any graininess from the resulting render, to give us a high-quality output in a reasonable timeframe.

We then built a simple model of an articulated desk lamp. Built as a single mesh and composed of simple primitive objects, all starting as cylinders or cubes, we developed it initially in a completely linear vertical configuration.

We then created vertex groups for each distinct portion of the lamp and assigned those parts of the lamp to those vertex groups. From the bottom up, these groups were:

  • base
  • pivot
  • upperarm
  • elbow
  • lowerarm
  • wrist
  • shade

We then added a spot light to represent the lamp’s bulb.

Next we generated a new armature. In edit mode, we scaled the initial bone until it was just the size of the base vertically and called it base, the name matching that of the vertex group in the lamp model. We then extruded the tip of this bone vertically to the centre of the first hinge pin in the model. This bone was named pivot again matching the name of the corresponding vertex group. We repeated this until there was a bone, named for the corresponding vertex group, across each section of the model.

We then returned to edit mode and, selecting first the armature and then shift-selecting the model, we used Parent | Armature Deform from the object menu to associated them together. The mesh became a child of the armature. Selecting the armature and changing to Pose mode, we were able to see how rotating the bones allowed us to move the model in a simple and non-destructive way.

We then wanted to move the light with the armature as well, as it currently remained in space where we’d located it originally. To do this we selected the spotlight object and added an object constraint tying it to the the shade bone in the armature, as shown below. This moved the light, so we needed to reposition and rotate it again to get it in the correct location.

The final step was adding an inverse kinematic control bone into the rig. Moving an inverse kinematic (IK) bone automatically moves all connected bones to try to follow the movement of the control bone. In the armature, in edit mode, we added a single bone and located it near the rim of the lamp shade. We called it “control” and, selecting it and then the shade bone, used Armature | Parent | Make | Keep Offset to join them.

We then switched to pose mode. Once in pose mode, we could add an IK constraint to the control bone as shown below. All defaults here are fine in this case.

Then we saw that moving this bone in Pose mode caused the rest of the lamp to follow, however some parts of the lamp were moving in ways we didn’t want. The final step was to place some IK limits on certain bones in the Bone Properties Panel. For the base we locked x, y and z because we didn’t want it to rotate at all:

For pivot and shade, we locked then in x and z, this will allow them to turn around their own axis but not bend over. For all the others we locked them in y and z allowing them to bend over corresponding to the way they were pinned in the model.

Files for these final models can be found on our Sharepoint site.

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