The book is well organized, and subjects are presented in a logical sequence: The Z domain makes a lot more sense if one first understands the S domain. The writing style is excellent, and has a way of explaining potentially confusing material, in a simple, clear manner. The mathematics throughout the book helps explain the much of theory, but if the reader doesn't care for the math, an understanding of the subject can still be gained without it.

Many college texts approach the subject from theory alone. While this book also provides the theory, it also presents the practical application side in a perfect balance. It is apparent that the author has worked in the real world. Also appreciated was the free Model-Q software examples sprinkled through out the book. They enable a reader the ability to experiment with the examples, and gain a better understanding of each of the subjects.

While this text is a very thorough, where a reader wants to explore a subject further, the numerous references to other sources are everywhere. No matter how much you think you may know about the subject, there is something everyone can learn from this book. This book is control systems A-Z, and is the best book I have seen on the subject. I highly recommend this book to anyone regardless of his or hers expertise level.

-Dave Trapasso


The most useful book available on control theory   November 6, 1998
John Nagle (Menlo Park, CA USA)
18 out of 19 found this review helpful

I have a whole shelf of control theory books, and this one is the one I use most. Ellis is one of the few people writing on control theory who actually designs working industrial control systems for a living. All the usual theory is in there: Laplace transforms, Z-transforms, and the S-plane. But this author has a much clearer idea about what actually works in the real world than most control theorists.


A great book for practicing engineers!   November 6, 2000
Ted Copperthite (Tustin, CA USA)
10 out of 11 found this review helpful

George Ellis does a great job of bridging the gap between academia and industy in Control System Design Guide 2nd Edition. This book gives the practicing engineer the information necessary to put into practice much of the theory that he/she learned in the university. The book primarily focuses on motion control and modeling of motion systems. If you are working on a control system and would like to make sure you get the performance you need, you should buy this book.


A Practical Hads-On Guide to Control System Design   June 29, 2000
Dan Carlson (St. Paul, MN)
6 out of 6 found this review helpful

This book is NOT just another academically oriented controls textbook. This book focuses exclusively on servo and motion systems. It presents highly complex topics, but avoids relying on detailed mathematical analysis, and instead emphasizes practical approaches that can be applied by anyone working on drive and motion systems. The book coveys complex topics in a clear and enlightening manner. Perhaps the most outstanding feature of this book is its use of ModelQ®. ModelQ® is a Windows© based modeling and simulation program written by the author and available at his website. It is used to illustrate and demonstrate various control concepts. ModelQ® has a very easy and intuitive user interface. ModelQ also contains a Digital Signal Analyzer (DSA). The DSA is a graphical display of the Bode plot (gain and phase) of the transfer function for the selected system output vs. the selected input. While this topic is heavily covered in most college controls courses and textbooks, few convey an understanding of the frequency domain performance of systems as clearly as this book and ModelQ®. The book has an excellent chapter on compliance and resonance. The effects of gearboxes, direct coupling, damping, and inertia mismatch are explored in depth. The PID is examined extensively. Six forms of PID are presented. The effects and interaction of each PID term is discussed. The strengths and drawbacks of each controller, as well as tradeoffs in simplicity and complexity, are summarized in a comparison chart. A flow chart to select the best controller structure based on needs is presented. Traditional tuning, such as "seat of the pants" and Zielger-Nichols is discussed. A flow chart based on frequency zoned tuning is presented that results in a simple, repeatable tuning technique. An entire chapter is provided on feed-forward techniques and how feed forward can be used to dramatically improve control system performance without any risk of stability problems. The chapter on motors covers motor design and construction, synchronous, induction, and reluctance motors, magnetics theory, motor speed- torque curves, linear & rotary motors, commutation, field weakening, power bridges, modulation, and flux-vector algorithms. I believe you will thoroughly enjoy the Control System Design Guide. This book covers a broad range of control topics, and addresses them in the framework of servo systems in a practical and application-oriented manner. Whether you are a controls technician or advanced degreed control engineer, this book will definitely make you more skilled and practiced in the art of control system design for servo and motion systems. I highly recommend Control Systems Design Guide as an extremely practical and thorough servo system controls reference.


Control System Design Tapestry   June 18, 2000
Steven L. Reid (Santa Barbara, California, USA)
5 out of 5 found this review helpful

I attended a seminar given by the author in May 2000 and was given an early copy of this book. Without question, the book should be owned by anyone involved with feedback control systems. While solidly grounded in theory, the content of the book stresses the practical side of control systems. The subject matter is primarily directed towards motion control but the majority of the book would be useful to those involved with process control or other control loops.

The book is well organized and clearly written. You are never left wondering what the author was trying to convey. Most importantly, the book delineates control systems as they are actually implemented today. The book stresses the different types of PID control loops that are used, why and when they are used and how to tune them in detail. Command feedforward and disturbance responce is covered as an integral part of the control loops, subjects that are critically important to modern control systems but are often ignored in other control textbooks. There are two chapters on non-linearities and loop resonance's, what they are and how to deal with them including limitations to the fixes. Some new, practical, cutting edge control enhancements are also discussed.

The book uses a Windows based modeling program to simulate how real control systems work. If you can point and click, you can use this simulator. Although this program is called a learning tool, I'm certain it will be used to simulate real systems.

This book, in my opinion, is a tour de force work for control system design, implementation and tuning.