Introduction

Nonlinear systems are everywhere, yet most engineering curricula devote very little time, if any, to them. The reason is twofold: first of all, there is no general theory describing arbitrary Systemnonlinearnonlinear systems. Second, the theory of linear systems is effective in facilitating the design of many real-world systems. In fact, for sufficiently small input signals, the behaviour of most nonlinear systems can be approximated by a linear model. As a consequence the majority of engineered systems are designed based on linear system theory and their usability is limited in one way or another by the deviation of the real system from the assumed linear behaviour. This book is intended to give engineers a powerful tool to model, understand and reduce the impact of mild deviations from linear behaviour and thereby design better systems.