Part 1: Setting up the Skeleton

 

First of all we have to build the model, in this case I have pre-built one so that we can go straight onto the subject of animation. This is a custom animation, if you are creating an animation for a game engine there may be certain procedures to follow, there may even be a pre-created skeleton you can use with animations already present. This tutorial only teaches the concept of 3D model animation. First; we have to add joints to the model at areas where we want mesh deformation to occur.

This is my model, I am assuming you already have a model that you want to animate. We want to keep the animation simple so we will place bones at key joints in the model, to resemble the most important joints of the human skeleton when it comes to a walk cycle.

  1. Select the Joint tool from the Model tab in the Toolbox.
  2. Make sure you are not in animation mode. Go to the front wireframe view and place a joint approximately in the centre of the pelvis where the spine would join. The first placed joint is the root joint for the whole skeleton. As this joint is in the centre of the model (roughly speaking) we will make it the root joint.

  1. To create the left and right extremities of the pelvis (we will call them left and right hip) you have to select the middle pelvis joint before creating the left and right hip joints. So first place the left joint, then select the middle pelvis joint again and place the right joint to give you something that looks like this.

  1. From here you should be able to place all bones for the rest of the skeleton. Use the image below to place the rest of the joints. Remember to have the 1st joint in the area selected before you place the next, e.g. have left hip joint selected before you place the left knee joint, the left knee joint selected before you place the left ankle joint etc...

  1. This gives us our basic skeleton, we still have to add to it. We still have to add the foot joints and align all the joints so they resemble the human skeleton. So, in the side view add a foot ball and toe joint to the foot (remember to have the ankle joint selected before you place the foot ball joint, etc).

  1. Now comes the boring bit, go through all of the joints and name them as they are labeled in the images above. First highlight the joint name (joint1, joint2 etc...) in the joint selector box in the joints tab of the Toolbox then type the appropriate name in the box beside the Rename button then click the Rename button. Remember that while renaming the joints you are looking at the model from the front, therefore your left and right sides are reversed, so take special consideration when you rename the joints as you want to name the joints from the perspective of being the model, so to speak.
  2. Now that all the joints are named we can re-position them so the skeleton represents a human skeleton. Take consideration when re-positioning the joints, remember that the joint is the centre point for deformation of your mesh in that area. Try to model as accurately as possible the position of joints in the human skeleton, it is only this way that you will get an animation that looks like a human walking. The final set-up of my skeleton (viewed from the side so you can see the position of joints) is shown in the following image.

Note: You may wish to spend some time fiddling with the positions of the joints so as to get the best results. You will find the more experience you have the more you will appreciate the exact positioning of joint so that model deforms in the best possible way.