[...]... view control theory When analog integrators were connected to simulate a system, the list of inputs to each integrator came to be viewed as a set of state equations, with the output of the integrators representing state variables 91239.indb 7 10/12/09 1:40:43 PM 8  ◾  Essentials of Control Techniques and Theory Computer simulation and discrete time control go hand in hand together At each iteration of. .. separate the essentials from the ornamental But perhaps that is too dismissive of the mathematics that can help us to understand the concepts that underpin the controller’s effects And if you write up your control project, the power of mathematical terminology can elevate a report on simple pragmatic control to the status of a journal paper 1.1 The Origins of Control We can find early examples of control. .. that the rate of loss of heat is proportional to the temperature above ambient, so we see that if we write T for temperature, dT = k (T − Tambient ) dt 9 91239.indb 9 10/12/09 1:40:46 PM 10  ◾  Essentials of Control Techniques and Theory Figure 2.1 A cooling cup of coffee Figure 2.2 A leaking water butt If we can determine the value of the constant k, perhaps by a simple experiment, and then the equation... Erskine Fellowship by the University of Canterbury, New Zealand, where he spent February and March 2003 In December 2006 he received an achievement medal from the Institution of Engineering and Technology, London His published books include: Essentials of Mechatronics, John Wiley & Sons, June 2006; Controlling with Computers, McGraw-Hill, January 1989; DIY Robotics and Sensors on the Commodore Computer,... All too many students regard control theory as a backpack of party tricks for performing in examinations “Learn how to plot a root locus, and question three is easy.” Frequency domain and time domain methods are often pitted against each other as alternatives, and somehow the spirit of the subject falls between the cracks Control theory is a story with a plot State equations and transfer functions all... results of the Walking Robot unit led to the foundation of Portech Ltd., which for many years supplied systems to the nuclear industry for inspection and repair of containment vessels Other units in the Robotics Research Group have had substantial funding for research in quality control and in the i ­ntegration of manufacturing systems with the aid of transputers In April 1992 he took up a Chair of Engineering... Research funding and concerned the guidance of a tractor by machine vision for very accurate following of rows of crop Prototypes of the system went on trial on farms in Queensland, New South Wales, and the United States for several years Novel techniques are being exploited in a further commercial project Other computer-vision projects have included an automatic system for the grading of broccoli heads,... new value to H It will work as it stands as a line of Basic For C or Java add a semicolon We can add another line to calculate the time, t = t + dt To make a simulation, we must wrap this in a loop In one of the dialects of Basic this could be: while (t < tmax) H = H + (-k*H + u)*dt t = t + dt 91239.indb 11 10/12/09 1:40:49 PM 12  ◾  Essentials of Control Techniques and Theory wend or for JavaScript... Version 6.0 of Visual Studio was easy to use, based on the concept of forms on which graphs could be plotted with very similar syntax to QBasic There are two problems with Visual Basic 6.0 Firstly, it probably cost more than this book, secondly, it has been superseded and might be unobtainable Microsoft is now offering a free download of Net versions of Visual C ++  and Visual Basic at www.microsoft.com/express... intentionally left blank Chapter 1 Introduction: Control in a Nutshell; History, Theory, Art, and Practice There are two faces of automatic control First, there is the theory that is required to support the art of designing a working controller Then there is further, and to some extent, different theory that is required to convince a client, employer, or examiner of one’s expertise You will find both covered . Nyquist Plot 14 8 11 .3 Nyquist with M-Circles 15 1 11 .4 Software for Computing the Diagrams 15 3 11 .5 e “Curly Squares” Plot 15 4 11 .6 Completing the Mapping 15 5 11 .7 Nyquist Summary 15 6 11 .8 e Nichols. Chart 15 6 11 .9 e Inverse-Nyquist Diagram 15 8 11 .10 Summary of Experimental Methods 16 2 12 The Root Locus 16 5 12 .1 Introduction 16 5 12 .2 Root Locus and Mappings 16 5 12 .3 A Root Locus Plot 16 9 12 .4. h1" alt="" Essentials of Control Techniques and Theory 912 39.indb 1 10 /12 /09 1: 40:29 PM This page intentionally left blank Essentials of Control Techniques and Theory John Billingsley 912 39.indb