ABSTRACT
Most people are familiar with human anatomy—at least from an intuitive or gross perspective. The human body has three kinds of muscles: cardiac, smooth, and skeletal. This chapter provides a presentation of conventions used in gross modeling. The soft tissue connecting the vertebrae are usually modeled by nonlinear springs and dampers. The movement and constraints of the joints is governed by the soft tissue connecting the segments—that is, the ligaments, discs, tendons, and muscles. With the torso being the largest segment of the human frame, the position and orientation of the other segments or limbs are usually measured relative to the torso. The concepts of flexion and extension are especially important in studying head and neck movement and injury. The chapter concludes with a consideration of the major muscle groups and with a presentation of anthropometric data. The term extension can be misleading in that, in structural mechanics, extension refers to elongation, the opposite of shortening or compression.
