Thus far we have discussed how to control continuous-time systems for both state-feedback and output-feedback problems. With today’s high performance real-time systems, the control algorithms developed in the continuous-time framework are typically implemented on a sampled-data system. As long as the sampling rate of the controller is high with | Stable Adaptive Control and Estimation for Nonlinear Systems Neural and Fuzzy Approximator Techniques. Jeffrey T. Spooner Manfredi Maggiore Raul Ordonez Kevin M. Passino Copyright 2002 John Wiley Sons Inc. ISBNs 0-471-41546-4 Hardback 0-471-22113-9 Electronic Part IV Extensions Stable Adaptive Control and Estimation for Nonlinear Systems Neural and Fuzzy Approximator Techniques. Jeffrey T. Spooner Manfredi Maggiore Raul Ordonez Kevin M. Passino Copyright 2002 John Wiley Sons Inc. ISBNs 0-471-41546-4 Hardback 0-471-22113-9 Electronic Chapter 13 Discrete-Time Systems Overview Thus far we have discussed how to control continuous-time systems for both state-feedback and output-feedback problems. With today s high performance real-time systems the control algorithms developed in the continuous-time framework are typically implemented on a sampled-data system. As long as the sampling rate of the controller is high with respect to the system dynamics there is typically no problem with this approach. When the delays associated with the discrete-time nature of the implementation are large however it is possible that closed-loop system performance will become poor or even unstable. In this chapter we will study how discrete-time designs may be used to improve performance when dealing with discrete-time systems. Developing a controller in the continuous-time framework even if the controller is to be implemented in a sampled-data system allows the designer to take advantage of a number of intuitive nonlinear design techniques such as nonlinear damping. There may be times however when the sampled-data nature of the implementation forces us to consider the system delays. In these cases it may be possible to develop a discrete-time model of the plant and directly develop a controller in the discrete-time framework. These two approaches continuous and discrete to the design of a controller for a sampled-data system are shown in Figure . We will be interested in the .
