Tutorial: Articulated Armatures

This tutorial will introduce the basic ideas behind an animation armature by setting up a jointed structure to create visual choreography. Our interest is in conveying an idea, feeling or mood through movement. The use of a mechanism both limits and extends the outcome; by constraining movement to a few degrees of freedom, a different quality of motion is produced than free-hand motion. But it also paves the way toward automation which will extend the rendering of a scene to include programmed patterns.

Objectives

At the end, you should be able to do the following:

  1. identify components from our automation kit: flanges, links, shoulder screws and M5 nuts, washers.
  2. set up a rotating turntable on an optical breadboard.
  3. assemble a serial-chain armature using shoulder-screw pivot joints.
  4. set up a slider rail on an optical breadboard.
  5. hand-puppet an armature with two or more degrees of freedom in an abstract visual choreography.

Deliverables: please finish setting up your scene and shoot a short video (e.g. 30 seconds) using one of the lab Sony a6000 cameras, available in-class or from the IDeATe Lending desk. The video should emphasize a visual choreography created from the use of on-screen or off-screen mechanical armatures.

The video should be uploaded to Vimeo and embedded in a short blog post. Please assign all group members as authors on the post. This is due Monday at 5PM.

Please have your workstation cleaned up and all materials put away prior to the start of class next Tuesday.

Agenda

  1. Visual walk-through of armature demonstrations.
  2. Visual walk-through of mechanical components.
  3. Demo of turntable assembly using sheet metal screws.
  4. Demo of pivot assembly using shoulder screws.
  5. Demo of slider track assembly.
  6. Discussion of the language of kinematics: degrees of freedom, translation, rotation, pin joint, serial-chain mechanism, parallel versus series actuation.
  7. Form working groups for exercise as assigned.
  8. Each group should choose a basic, simple set of objective for a moving choreography. Decide on roles and work in parallel. Please keep it simple and work quickly.
  9. The instructors will circulate and coach each group.
  10. After the hardware is set up, practice puppeteering the action. Remember, the emphasis is on finding the choreography possible with the kinematics of an armature mechanism.
  11. Use one of the Sony a6000 cameras on a tripod to record short clips of the scene.

Approaches

  1. Please focus on the movement of each element and how they compose together to form choreography.
  2. The movement includes the shape of the paths formed in space, the rhythm and tempo, the syncopation of multiple movements, the ictus of inflections.
  3. The armature need not be visible; in conventional animation it usually refers to the hidden structure within a stop-motion puppet. The visible elements could be found objects, fabric, an optical element such as a filter, light reflected from a moving mirror, etc.