Feedback-Systems

This book is a wonderful introduction to the more advanced ideas of control theory. But it is written with emphasis on classical control and transfer functions (which makes for a good introduction). The problem is that this book is no longer in print. However, the copyright has reverted back to the authors. And they have kindly decided to make the book available for free! Simply do a google search for "Feedback Control Theory", and you will find it.

This is a excellent book for graduate student working in Control. It starts of with concepts in control and gradually goes into the details of multivariable control. Presentation on $\mu$ is clear and concise. I really liked the material on decentralzed control and control structure selection. Prof. Siguard Skogestad and Prof. Ian Postlethwaite did a excellent job. However, I wish there were more problems at the end of each chapter focussing on the research issues.

This is simply the best book written on nonlinear control theory. The contents form the basis for feedback linearization techniques, nonlinear observers, sliding mode control, understanding relative degree, nonminimum phase systems, exact linearization, and a host of other topics. A careful reading of this book will provide vast rewards. A fantastic book.

When it comes to automatic controls, Dr. Smith is incredibly knowledgable. Unfortunately, this does not always come through in this book. The book suffers from lack of sufficient worked examples to assist the reader in gaining competency in this area. At times, the theory takes leaps that leave the reader wondering how they did that. As with most engineering texts, once the reader fills in the missing steps the concepts become clear and logical. Overall, this is a worthwhile text from which the subject can be learned.

Note the word 'truely'. Just the section on Installed Flow Characteristics on control valves is enough to worth buying this book. The writers solved the mystery on why an inherent "Equal Percentage" control valve behaves "Linear" when installed; and why an inherent "Linear" control valve behaves "Quick Opening" when installed in most chemical processes being controlled (should factors such as the over-sized factor, the fraction of the dynamic pressure taken by the control valve, and the rangeability of the control valve are overlooked). The writters did it by vigorously deriving the Installed Characteristics from the universal definition of "Cv" (first introduced by Masoneillan in industry, now adopted by ISA), fluid mechanics, and simple algebra, from which the installed gain at various percent-opening of most control valves is derivable analytically by math. Excellent job done. I have used this book since mid 1980's in my career as an Instrument Engineer and recently I used it in writing engineering specifications for control valves. For 15 years before mid 1980's, a book like this has been in my search list. While control theory can be easily found in many texts, unique relevant work experience of writters cannot. Whether you are a Chemical Engineer or not, if your work is related to Automatic Process Control, I will recommend you to buy this book. Before it gets sold out, I am going to buy the lattest edition tomorrow since I believe this book will be useful for at least the next 50 years from now in any process control industry.

llevo trabajando el texto desde 1998,obteniendo muy buenos resultados en la enseñanza del control de procesos. en particular creo que la obra presenta un excelente equilibrio entre la teoría y la práctica. adicionalmente los problemas enfrentan al estudiante con situaciones muy cercanas a las que encontraran en su vida profesional. a nivel de sugerencia para proximas ediciones, considero debe ser incluido el tema de los grados de libertad para control de plantas completas.

I am a student of Graduate School, and my major is Adaptive Control. I consider this book very good book for me, especially because it summarizes and covers most of the basic concept and method about control engineering, which I sometimes forget. So, by having this book now, I can anytime find and reread the part I have forgotten. Of course, it will be better if you also accompany this book with others books which explain more detil about control.

I'm currently taking a Feedback Control Theory course at the undergrad level, and I think this book is an excellent exposition of classical control theory. Our text for the course is Feedback Control of Dynamic Systems, written by people from Stanford. Schaum's Outline actually has more *theory* than the textbook we are using. It eliminates all of the frills and pretty colored diagrams in favor of exposing everything an undergraduate would have trouble with. And for those people who think the emphasis is only on problem solving, this "Outline" has more mathematical proof than the book from Stanford I just mentioned! I highly recommend using this book to get off on the right foot in control systems, whether you are an engineer just learning the material or an undergraduate; it solidifies the foundations of the theory so that practical problems will come more easily. Also, it is a practical book as well.

I only bought this book after I went through undegraduate control and digital control classes. And after getting very fragmented knowledge of these disciplines, this book was very good in helping me sort it out. Yes, if you don't know a thing about control theory or don't have basic math background, it probably is hard to grasp without any other sourses. But if you have some basic understanding of the subject, then it is a very good review and reference for the classical control theory. I used this book for review before taking a PhD preliminary exam in controls, and it helped a lot. Now I am using it for the same reason for the job I just started. I like the way it describes digital control theory in parallel with the continuous-time controls, which is the best way to understand the discrete-time tools, instead of taking a whole other class starting from scratch. Constant examples to illustrate the theory are very good, so are the excersises. Mind you, this book doesn't go into details like some 800pp. volumes but it doesn't leave out anything important either. I highly recommend this book to undegrad and grad students, as well as a reference for the engineers.

There are two main good points to this book: 1) there are many citations (references), not only to articles but to companies mentioned; 2) tons of photos, though many I found insufficiently captioned (ie, only a person who's seen the device would understand it from the picture and text). Good explanation of basic haptic & VR concepts.

The main bad points are: either too terse or too superficial, no real insight, pedantic.

The two halves of the book were quite different. The second half of the book is more interesting, but first things first:

Basically, the first half of the book is a compilation of technical information on existing haptic devices and haptic software for VR applications. It's basically regurgitation of data, very terse, factual, and boring. No analysis or insight. More a reference. Loaded with truisms like (paraphrasing) "This device requires more force to activate, so it's found to increase fatigue quicker and potential for injury". Duh!

Second half of the book deals with applications: physical modelling (surface deformation, ...), human factors (how haptics affect tasks, ...), medical, etc. Short chapter on future trends, which again I found unenlightening. But there were a few good discussions here and there, about collision detection and the like, but I found they were few and far between.

In conclusion, what I mostly got out of this book were a few references to look up for further reading, an idea of the vaste array of technologies used in haptics, some pictures of real haptic devices, and an indigestion of technical facts. I got some insight into certain issues in collision detection, and some feeling for how limited and simplistic the field of VR haptics still is.

I would have liked to see more of a debate on whether certain applications were even sensible, how much computing power is required for certain tasks, etc. Not easy questions to answer, but why bother write a book with only stuff most people could figure out on their own?

One of the most common complaints about virtual world experiences is that the lack of physical sensations in the environment. Visual simulation is nearing photographic quality, and 3D sound is very convincing. But as soon as one touches a virtual object, or picks up a virtual car and tosses it into the next simulation, one has a great sense of incompleteness. "Why", the question is often asked, "can't I feel anything in this great virtual reality?"

There is no easy answer to that question, despite the millions of
dollars and thousands of hours spent trying to understand and
duplicate our incredibly subtle and complex haptic senses. However, at last, we can at least understand the magnitude of the problem, and the state of the art. Grigore Burdea, an Associate Professor at the CAIP Center of Rutgers University, spent most of last year engaged in research and writing about this missing dimension of VR. His new book, Force and Touch Feedback for Virtual Reality, is the result of that effort. As far as I know, there is no more complete or erudite book on the subject.

Burdea careful lays the groundwork for his survey of force feedback (resistive impulses, FFB) and tactile feedback (sensations of texture, temperature, etc., TFB) devices and concepts by providing a thorough background in human proprioception. He shares with the reader the fruits of his research: how the various receptors in the skin, muscles, bones and joints interact, how the nervous system perceives and conveys haptic data, reaction times and bandwidths of human response, and much more. He describes studies on the resolution of feeling, the average strength of various parts of the body, and time to fatigue. All in all, one is left with the impression that
Burdea is a man with a good feel for the subject.

Interestingly, reading this book made me all the more pessimistic
regarding our likelihood of ever having good FFB devices for general use. The problem is manifold. As Burdea points out, the range of forces that human beings are capable of feeling and reacting to is great. It spans several orders of magnitude, from the gentle caress of a lover brushing away a strand of hair, to the rough effort required to push a recalcitrant automobile.

Designing one device, even a hybrid device, to duplicate this range of force is a daunting concept. Furthermore, FFB devices must be grounded. That is, they must have something to push against. A portable FFB device would necessarily be of limited scope.

The outlook for TFB devices is much better. Because these devices are not resistive in nature, they can (indeed, should be) small and portable. A glove with an inner surface made of nano-mechanical effectors is conceivable, and could possibly provide realisticsensations of friction, slippage, texture, and other sensations. However, the likelihood of such a device being built in the next few years is slim.

Lacking any ideal solution, many experimenters and manufacturers,
Burdea among them, have developed limited force and tactile feedback devices. Many such devices, such as the (award-winning) Phantom, and the Impulse Engine, are commercially available and are finding acceptance in specialty applications. Most people in the VR business are familiar with the GROPE experiment carried out at UNC chapel Hill, in which a large FFB arm, designed for working with radioactive materiel, has been used to evaluate the value of FFB in molecular docking research. Medical simulation is an important use of FFB, and gamers are starting to see low-cost devices built into joysticks and other controllers. All of this, and a great deal more, is carefully covered in this book.

Were I giving a course in haptic simulation, this would be my text of choice. I recommend it without reservation to anyone considering adding haptic feedback to a simulation. If you haven't covered this material, you would need a lot of time to catch up. Luckily, Burdea has done it for us.

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This review first appeared in CyberEdge Journal, October 1996.

© CyberEdge Information Services, Inc. 1996

This a great textbook on this new human-computer interface technology. The book is destined to become a classic of this field due to its in-depth, comprehensive treatment of the haptic technology. It was no suprise to me to see it is cited in many technical articles.

The book present not only technical data (actuators, force and touch feedback devices) but also the basic information related to human haptic sensing. In addition, the book complete its review of haptic systems with a chapter on human factors, which contains a collection of interesting experiments attesting the potential of this new technology. Unfortunately haptics is still in its infancy which makes it difficult to speculate on its future (as concluded in the last chapter).

In short the book will give you a good understanding of this new technology, being also a very good reference compendium.

this book presents a theory of control systems clearly and lucidly and presents the matlab simulation of control systems in a way which is most needed for brush-up in the eleventh hour. the author has taken keen interest in presenting the subject right from the grassroot level and a gradual development of the concepts is presented in the easy-to-use tool like way. i firmly believe that this should be in the bag of all engineers working on simulation of control systems.

a will "briefly" written book which assumes that the reader has the basics of feedback control and matrix algebra. Each chapter has a MATLAB section at the end which shows some important commands (not codes) that are relevant to the chapter's material. Excellent chapter on robstness design.

This book begins with a simple but excellent mathmatical review. Then covers control strategies and symbology. The book starts out very basic for the beginners and then covers more complicated control scemes. This book is great for the beginner and a good review for the experienced. Topics include: Flow, Temperature, Level, and Pressure Control Loops; Modifications to Standard PID Control; Tuning; Cascade Control; Ratio Control; Feedback and Feedforward control.

All topics are covered in a straightforward, easy to understand manner. I recommend this book for the beginner.

This book is very simple and preliminary. I had bought this book with the intention of getting deep insight into feedback compensation networks that go in day to day power supply circuits. Unfortunately, I was disappointed. Even some general books like Switching power supply and Power supply cookbook have good amount of detail on compensation circuit. If you are a beginner, then this is probably the book for you.

I took control theory in college and found it hard to grasp. The mathematics involved in analyzing control loops with higher order systems became daunting and difficult to postulate. Several years out of school, I ordered this book to help refresh myself in the principles of control loop design. Although the information presented is practically valid, the information is hard to decipher. The author's writing style is difficult to follow sometimes. I almost think the book was written quickly due to partially completed thoughts in sentences, awkward sentence structure, and run-on sentences. The chapters seem to be out of order and I found myself jumping forward and backward trying to tie the author's concepts together. I think that if one had never taken a control theory class and read this book, they would struggle with the topic due to the amount of "de-cyphering" required to comprehend the text. I believe the author does know what he is writing about but has trouble communicating his ideas in written text. If the author intends to write again, I would suggest a third party somewhat proficient in the subject manner check the grammar of the text.

Many years after leaving college, I've started playing with closed loop control systems for small toys. (Think: science projects for kids!)

This book was an excellent re-introduction to Bode plots, transfer functions, control loops and compensation. There was a wealth of practical information on modelling control loops containing various degrees of complexity. The sections on second-order loops and output stiffness were particularly useful for my purposes. Your mileage may vary depending on your application, but the book includes a good range of examples, and has something to offer any engineer doing practical circuit design.