Page 20 - Dynamics of Mechanical Systems

0593_C01_fm Page 1 Monday, May 6, 2002 1:43 PM

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Introduction

1.1 Approach to the Subject
This book presents an introduction to the dynamics of mechanical systems; it is based
upon the principles of elementary mechanics. Although the book is intended to be self-
contained, with minimal prerequisites, readers are assumed to have a working knowledge
of fundamental mechanics’ principles and a familiarity with vector and matrix methods.
The readers are also assumed to have knowledge of elementary physics and calculus. In
this introductory chapter, we will review some basic assumptions and axioms and other
preliminary considerations. We will also begin a review of vector methods, which we will
continue and expand in Chapter 2.
Our procedure throughout the book will be to develop a general methodology which
we will then simplify and specialize to topics of interest. We will attempt to illustrate
the concepts through examples and exercise problems. The reader is encouraged to solve
as many problems as possible. Indeed, it is our belief that a basic understanding of the
concepts and an intuitive grasp of the subject are best obtained through solving the
exercise problems.

1.2 Subject Matter

Dynamics is a subject in the general field of mechanics, which in turn is a discipline of
classical physics. Mechanics can be divided into two divisions: solid mechanics and fluid
mechanics. Solid mechanics may be further divided into flexible mechanics and rigid
mechanics. Flexible mechanics includes such subjects as strength of materials, elasticity,
viscoelasticity, plasticity, and continuum mechanics. Alternatively, aside from statics,
dynamics is the essence of rigid mechanics. Figure 1.2.1 contains a chart showing these
subjects and their relations to one another.
Statics is a study of the behavior of rigid body systems when there is no motion. Statics
is concerned primarily with the analysis of forces and force systems and the determination
of equilibrium configurations. In contrast, dynamics is a study of the behavior of moving
rigid body systems. As seen in Figure 1.2.1, dynamics may be subdivided into three sub-
subjects: kinematics, inertia, and kinetics.

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