Rigging for animation

- If you want to animate your models, you may need to rig them. Rigging makes a model easy to animate. It can be as simply as connecting some parts together, or as complex as building custom interfaces. Character animation is where you'll see a lot of rigs. Character rigging starts with the model arms out in a neutral pose. A skeleton is then drawn or fitted to the mesh. Skeletons can be built a joint at a time, or they can be pre-built, such as AutoDesk's HumanIK for Maya. Once the skeleton is in place, we can go further by adding user friendly controls to it. These may use inverse kinematics to control entire limbs, or they may control a joint at a time. Once controls are added, the character's model is connected to the skeleton using a process called skinning. Skinning assigns each part of the mesh to the skeleton. The final result allows the animator to realistically deform and manipulate the character. For some characters, you'll need to create a face rig. Many face rigs start with a library of facial poses, one for each expression. Manipulating the weights controls the face. We can go further by adding an interface that controls all of the facial features. Rigging is not limited to just characters. Other objects, such as vehicles, can also use rigging tools to make animation easier. Finally, rigging does not have to be confined to 3D either. People who animate in 2D packages, such as Flash or After Effects, can also benefit from rigs to speed the animation process.