Anatomy Based Models

Unfunded dissertation research by:
Ferdie Scheepers

Summary of Work
Artists study anatomy to understand the relationship between exterior form and the structures responsible for creating it. In this research we followed a similar approach in developing anatomy-based models of muscles. We considered the influence of the musculature on surface form and developed muscle models which react automatically to changes in the posture of an underlying articulated skeleton. The models were implemented in a procedural language that provides convenient facilities for defining and manipulating articulated models. To illustrate their operation, the models were applied to the torso and arm of a human figure. However, they are sufficiently general to be applied in other contexts where articulated skeletons provide the basis of modeling.

Human figure modeling and animation has been one of the primary areas of research in computer graphics since the early 1970's. The complexity of simulating the human body and its behavior is directly proportional to the complexity of the human body itself, and is compounded by the vast number of movements it is capable of. Although articulated structures containing rigid segments is a reasonable approximation of the human skeleton, most researchers use articulated structures that are too simple to be deemed anatomically appropriate. The shoulder, spine, forearm, and hand are typical examples where accuracy is sacrificed for simplicity. The more difficult problem of fleshing-out a skeleton is currently an active area of research. In several previous approaches, oversimplification caused undesirable or distracting results. Using flexible surfaces at or near joints is a poor approximation because many deformations (like bulging muscles) occur far away from joints. Also, producing intricate joint-dependent changes in the shape of the skin without considering the motivators for those shape changes seems implausible.

In this research we presented an approach to human figure modeling similar to the one taken in artistic anatomy — by analyzing the relationship between exterior form and the underlying structures responsible for creating it, surface form and shape change may be understood and represented best. We focused on the musculature by developing anatomy-based models of skeletal muscles, but many of the principles apply equally well to the modeling of other anatomical structures that create surface form, such as bones and fatty tissue.

http://www.accad.ohio-state.edu/~smay/Human

Siggraph '97 paper describing this research at:
http://www.accad.ohio-state.edu/~smay/Human/human.pdf

This research is also represented by the PhD research of Dr. Ferdie Scheepers