Dynamics of Rigid Body Systems

The purpose of a dynamics algorithm is to evaluate numerically an equation of motion; but, before we can evaluate it, we must first know what that equation is. This chapter introduces the equations of motion for a general rigid-body system, and presents a variety of methods for constructing them from simpler equations. These methods form the basis for various algorithms that appear in later chapters. However, the focus of this chapter is mainly on the mathematics of rigid-body dynamics, rather than on particular algorithms.