Constructing a Character Rig using XSI

Comparison of XSI's Biped Guide with my rig

XSI's default Biped Guide
When we look at the XSI's default Biped guide, which is generated by simply opening the Softimage XSI application, which by default opens a new window, we choose the Animate tool bar and open the Character settings, were the Biped Guide is located. Clicking on the Biped Guide opens an information window, which allows changes on the type of Biped Guide one requires to be made and then"ok" accepts the approved settings. The Biped Guide is a ready made skeleton that one can use to create a character from. However a Biped Guide is difficult to use because of it being unstable and underactuated, so for one to us it, there have to be some adjustments made to suit the type of character rig one may want to design. Choosing to use the Biped Guide can be advantageous when one has to construct a character in the shortest time possible, because all the controls are ready made. However changes would have to be made if the character has abnormalities, like for example the character rigging done for the animation, The Incredibles.

Rigging my Character

When it comes to rigging a character one has to consider a lot of things, the kind of character to be rigged, whether human or otherwise. Making the rig as simple as possible is a bonus, which in this assignment, was a normal human rig. We started off, creating one leg with the foot, which had four chain bones, the thigh, the calf and the foot which has two separate chains bones. The leg was then duplicated after a knee up vector was added to it as well as a foot control and foot roll. Then hip control was given to the rig.

The spine was then created using two chain bones and a curved null was placed within the spine to give it normal body movement. Three ribs were created to give the spine and body form and better control. Then the arm was created by giving it a shoulder blade, an arm, wrist and finally fingers. These were parented to the spine and given controls.

XSI Biped Guide is less time consuming as compared to my rig, which was created from scratch in a sequence I chose. I determined the shape and size and the constraints as well as the body mass and characteristics, while the Biped Guide restricts these. Overall the rigging I did was very difficult and it gave me an idea as to why constraints are necessary and how they help control the rig. There was also a better, clearer understanding as to why parenting is done in a rig and body controls are added.