Showing papers by "Petar V. Kokotovic published in 2005"
TL;DR: An adaptive recursive design technique is developed for a parametrically uncertain nonlinear plant describing the dynamics of a ship and an update law is constructed that bridges the geometric design with the dynamic task.
513 citations
TL;DR: An essential difference between path-following and reference-tracking for nonminimum phase systems is highlighted and it is shown that there exists a fundamental performance limitation in terms of a lower bound on the L/sub 2/-norm of the tracking error, even when the control effort is free.
Abstract: We highlight an essential difference between path-following and reference-tracking for nonminimum phase systems. It is well known that in the reference-tracking, for nonminimum phase systems, there exists a fundamental performance limitation in terms of a lower bound on the L/sub 2/-norm of the tracking error, even when the control effort is free. We show that this is not the case for the less stringent path-following problem, where the control objective is to force the output to follow a geometric path without a timing law assigned to it. Furthermore, the same is true even when an additional desired speed assignment is imposed.
203 citations
TL;DR: A dynamic version of unbounded time-varying scaling of the states for feedback laws for power integrator triangular systems which globally asymptotically stabilize (GAS) the origin despite the uncontrollability of the linearization.
23 citations
TL;DR: In this paper, the authors investigate limits of performance in reference-tracking and path-following and highlight an essential difference between them, showing that the smallest achievable L 2 norm of the tracking error is equal to the least amount of control energy needed to stabilize the zero-dynamics of the error system.
11 citations
TL;DR: In this article, a path-following problem for linear systems with unstable zero dynamics is solved, where the original control variable steers the system output along the path, and the path parameter θ is used as an additional control to stabilize zero dynamics with a feedback law which is nonlinear due to the path constraint.
7 citations
12 Dec 2005
TL;DR: This work develops a path-following algorithm for redesign of tracking feedback laws to reduce the control effort, applicable to feedback linearizable systems with stable zero dynamics.
Abstract: We develop a path-following algorithm for redesign of tracking feedback laws to reduce the control effort. Our algorithm provides a tradeoff between the control effort and the dynamic performance along the path, while maintaining the desired convergence to the path. It is applicable to feedback linearizable systems with stable zero dynamics. We illustrate it on a realistic hovercraft model, and compare the resulting control effort with control efforts of other path-following and tracking algorithms.
5 citations