Page - VI - in Control Theory Tutorial - Basic Concepts Illustrated by Software Examples

Preface I studyhownatural biological processes shape thedesignof organisms.Likemany biologists, I have often turned to the rich theoryof engineering feedback control to gain insight into biology. The taskof learningcontrol theory for abiologist or for anoutsider fromanother scientificfield is not easy. I read and reread the classic introductory texts of control theory. I learned the basic principles and gained the ability to analyze simple modelsof control.Thecoreof theengineering theorysharesmany featureswithmy own closest interests in design tradeoffs in biology. How much cost is it worth paying to enhance performance?What is themost efficient investment in improved design given the inherent limitation on time, energy, and other resources? Yet, for all of the conceptual similarities tomy own research and for all ofmy hoursof studywith theclassic introductory texts, I knewthat Ihadnotmastered the broad principles of engineering control theory design. How should I think simply andclearlyabout abasiccontrol theoryprinciple suchas integral control in termsof howabiological systemactually builds an error-correcting feedback loop?What is the relation between various adaptive engineering control systems and theways in which organisms build hard-wired versus flexible control responses? How do the classic cost-benefit analyses of engineering quadratic control models relate to the commonly used notions of costs and benefits inmodels of organismal design? After several years ofminor raiding around theperipheryof engineering control theory, I decided it was time to settle down andmake a carefully planned attack. I lined up the classic texts, from the basic introductions to the more advanced treatises on nonlinear control, adaptive control, model predictive control, modern robust analysis, and thevariousmetrics used to analyzeuncertainty. I could already solve a wide range of problems, but I had never fully internalized the basic prin- ciples that unified the subject in a simple and natural way. This book is the tutorial that I developed formyself. This tutorial canguide you toward broad understanding of the principles of control in a way that cannot be obtained from the standard introductory books. Those classic texts are brilliant compilations of knowledge with excellent drills to improve technical skill. But those texts cannot teach you to understand the principles of control, how to vii