Objective:
To rig the 3D character model, skin it and set controls ready for animation.
Rigging is a process of adding controls to a digital model to allow animators to move it around and act.
Techniques used:
Bone setup
Skinning
Control setup
Custom attributes
Challenges:
IK FK Switch
Skinning will be a challenging part. It's going to be hard to skin Shoulder, elbow, knee, ankle and thighs.
I checked the Orientation of the joints individually by enabling the Local Rotational Axis
The correct Orientation has to be set to individual joints so that
it becomes easy to set the Controls and more apt to rotate in a particular angle.
Now I set up the controls for the torso, only tricky part here is the Pelvis Control whose Pivot will be at the Abdomen Joint’s position.
But the Pelvis Control’s position will be with the Pelvis joint and Parent Constraint the Pelvis Joint.
Thus, creating the Human Pelvis movement.
Each Control will Parent Constraint the corresponding Joints
Ex: Abdomen Ctrl will Parent Constraint Abdomen Joint and so on
For the feet control I will group the IKs and change the pivot of the each group and create one custom attribute for each group created.
I will give min max values and connect their rotational value using Connection Editor.
Arm rig is the most challenging as I have to create both IK and FK controls.
Once I created the Arm joints, I duplicated them till Wrist joint twice.
I had the following set of joints which I put into different layers:
Shoulder joint main | Shoulder joint IK | Shoulder joint FK
Elbow joint main | Elbow joint IK | Elbow joint FK
Wrist joint main | Wrist joint IK | Wrist joint FK
The concept is the main joints should be controlled by the IK/FK joints.
So, I set up the FK controls for FK joints and IK controls for IK joints
Then I selected Wrist IK, Wrist FK and finally Wrist main joint and applied Orient Constraint. Followed the same for elbow and shoulder.
The result would be the main joint will be in the middle of FK and IK joints when any one is moved.
I needed a Control to Switch between IK and FK so created one curve and added IK and FK custom attribute.
Using Connection Editor, I connected the IKs and FKs
I used Set Driven Key to hide and unhide the controls while switching between IK and FK.
Ex: If the user chooses FK all the IK controls will be hidden and vice versa
I created a separate control for the fingers and custom attributes for the Finger control. I used Set driven key for controlling the stretch and curl of the fingers.
I used Joint Hierarchy skin binding mode for skinning the model. I used Paint skin weights to manually add influences on the vertices. Thus, acquiring a proper rig.
