HOW Do I ADD more flexibility Into my rigs?
Dave Pearson, Rotherham
When it comes to rigging in Maya, it’s never a case of one size fits all. Each technical artist will have their own techniques, which makes each rig unique to them. With that said, there are foundation techniques that everyone will use at one time or another to adapt and build upon to create a rig to suit their particular needs.
One of these techniques, which has been around for a while now, is known as the ribbon rig.
Broken down to the bare bones, this rig essentially puts control of the joints in the hands of a NURBS plane. You then deform the plane how you want and the joints follow. The beauty of this type of approach is its flexibility in that you can move the CVS around to deform the plane, giving you the opportunity to make all sorts of weird and wonderful shapes. Perfect for a cartoon character whose arms need to twist, bend and wiggle.
So how does it work? Well, attached to the NURBS plane are a series of follicles that follow the surface as it deforms, maintaining the correct orientation and position relative to the surface normals.
These follicles are the key to the whole system because you can parent your bind joints (which drive your character’s mesh) to them, meaning when the NURBS plane is deformed the follicles move, and where they move, the joints follow.
For example, let’s say that you’re building a rig for an arm. The ribbon would have maybe seven joints, one for each key pivot point, (shoulder, elbow and wrist), with two extra joints between these for twisting and deformation.
With the ribbon as your foundation you can then start to build the beginnings of a control rig to manipulate it. However, rather than editing the bind joints directly, you would use a skincluster to pull the NURBS plane around, as this is already in control of the joints.
It sounds complicated but it’s straightforward when put into practice, and the beauty of this approach is it’s also ideal for facial rigs.