| One of the most important problems in controls is command following or tracking. Though this area has been widely studied, there are still numerous unsolved problems of practical importance. The research presented in this dissertation deals with two problems in the area of tracking. The first involves obtaining reduced order feedback tracking controllers for multivariable systems, as well as assessing the tracking robustness of reduced order tracking controllers. The second involves the problem of achieving tracking without overshooting for certain command inputs.; The classical robust servomechanism is the standard method used to achieve multivariable tracking. The main disadvantage to this method is the potentially high order of the servocompensator, which often translates into a more expensive DSP for implementation. Therefore, a technique that results in a reduced order controller is developed, and certain robustness issues associated with reduced order control are discussed.; The problem of tracking a known reference without overshooting is of great practical importance in a number of applications. Currently, there does exist a usable design technique to achieve a non-overshooting response for certain systems. However, non-minimum phase systems, systems with reference inputs other than steps, and non-linear systems have received very little attention. Thus, several methods are presented which allow for consideration of various non-minimum phase, nonlinear, multiple output, uncertain systems. |
