Browse ORBi by ORBi project

- Background
- Content
- Benefits and challenges
- Legal aspects
- Functions and services
- Team
- Help and tutorials

Adaptive lambda -tracking for nonlinear systems with higher relative degree Bullinger, Eric ; in Proc. 39th IEEE Conference on Decision and Control (2000) Previous results for adaptive lambda -tracker have focused on nonlinear systems with relative degree one or on linear systems with higher relative degree. We extend the adaptive lambda -tracker to lambda ... [more ▼] Previous results for adaptive lambda -tracker have focused on nonlinear systems with relative degree one or on linear systems with higher relative degree. We extend the adaptive lambda -tracker to lambda -stabilize nonlinear system with higher relative degree. Only little structural information about the system to be controlled is needed. lambda -stability and convergence of the adaptation is proven for tracking a large class of reference trajectories. The design of the controller is very simple and intuitive, only few parameters have to be tuned [less ▲] Detailed reference viewed: 17 (0 ULg)Artifact-tolerant controllers for automatic drug delivery in anesthesia ; Bullinger, Eric ; et al in Critical Reviews in Biomedical Engineering (2000), 28(1-2), 187-192 This article presents a method for treating measurement artifacts in model-based control systems. A nonlinear modification to the usual observer structure is introduced to prevent the measurement ... [more ▼] This article presents a method for treating measurement artifacts in model-based control systems. A nonlinear modification to the usual observer structure is introduced to prevent the measurement artifacts from winding up the controller states. It is shown how stability of the closed loop system can he analyzed and an example of a successful application in a clinical study is provided. [less ▲] Detailed reference viewed: 18 (4 ULg)Some further results on adaptive lambda-tracking for linear systems with high relative degree Bullinger, Eric ; ; et al in Proc. of the 2000 American Control Conf. (2000) Several adaptive controllers which universally achieve the so-called lambda -tracking have been proposed in the literature. From a practical point of view, previous results are not usable for systems with ... [more ▼] Several adaptive controllers which universally achieve the so-called lambda -tracking have been proposed in the literature. From a practical point of view, previous results are not usable for systems with a high relative degree because of bad numerical conditioning. The paper presents a modified approach overcoming this numerical problem while achieving the same robust stability properties. Stability and convergence of the adaptation is proven for tracking a large class of reference trajectories. The design of the controller is very simple and intuitive, only few parameters have to be tuned and little structural information about the system to be controlled is needed [less ▲] Detailed reference viewed: 19 (0 ULg)Adaptive lambda-tracking in anesthesia Bullinger, Eric ; ; et al (2000) We present an adaptive controller for tracking reference signals of end-tidal concentration of anesthetic gas for automatic control in anesthesia. The adaptation scheme does not use any identification ... [more ▼] We present an adaptive controller for tracking reference signals of end-tidal concentration of anesthetic gas for automatic control in anesthesia. The adaptation scheme does not use any identification mechanism. Since only structural information on the system to be controlled is needed for the controller design, the controller is very robust to changes in the parameters of the system [less ▲] Detailed reference viewed: 27 (2 ULg)Adaptives λ-tracking für nichtlineare Systeme mit Relativgrad größer eins Bullinger, Eric ; Conference (1999) Detailed reference viewed: 8 (0 ULg)Artefakttolerante Regelungen für die Anästhesie ; Bullinger, Eric ; et al in Fortschritts-Berichte VDI, Reihe 17, Nr. 183 AUTOMED '99, Beiträge zum Workshop `Automatisierungstechnische Verfahren für die Medizin' (1999) Detailed reference viewed: 5 (0 ULg)Adaptive $\lambda$-tracking for Linear Systems with Higher Relative Degree---The Continuous Adaptation Case Bullinger, Eric ; in Proc. of the 5th European Control Conference, ECC'99 (1999) This paper presents a simple adaptive controller which universally achieves so-called X-tracking for linear systems where only little structural information about the system to be controlled is needed ... [more ▼] This paper presents a simple adaptive controller which universally achieves so-called X-tracking for linear systems where only little structural information about the system to be controlled is needed. The paper extends previous results to the case of systems with higher relative degree. Stability and convergence of the adaptation is proven for tracking arbitrary but sufficiently smooth reference trajectories. The design of the controller is very simple and intuitive and only few parameters have to be tuned. The robustness is increased by the introduction of a dead-zone in the adaptation, whose width X can be chosen by the user. In this paper a continuous adaptation law is used as opposed to the discrete law suggested in earlier papers. The’re are several advantages in using a continuous adaptation: Besides displaying a simpler structure the necessary gain to achieve the control goal will also be significantly lower in general. To demonstrate the performance the controller is applied to the model of a ball and plate experiment. [less ▲] Detailed reference viewed: 13 (0 ULg)Piecewise constant high-gain adaptive lambda-tracking for higher relative degree linear systems Bullinger, Eric ; ; in Proceedings of the 14th IFAC World Congress (1999), 5 In this paper we present an adaptive high-gain observer-based controller for linear, minimum-phase systems with known relative degree larger than one and known sign of the high-frequency gain. The ... [more ▼] In this paper we present an adaptive high-gain observer-based controller for linear, minimum-phase systems with known relative degree larger than one and known sign of the high-frequency gain. The adaptation scheme does not use any identification mechanism and is universal in the sense that it is independent of the system the controller is designed for. We prove that for any bounded and sufficiently smooth reference signal the modulus of the tracking error becomes smaller than an arbitrary small but fixed error bound lambda if t tends to infinity. All states of the nonlinear closed-loop system remain bounded [less ▲] Detailed reference viewed: 27 (2 ULg)A simple adaptive observer for nonlinear systems Bullinger, Eric ; ; in IFAC Nonlinear Control Systems Design, NOLCOS98 (1998) We present a high-gain observer for nonlinear uniformly observable SISO systems for which the high-gain parameter is determined adaptively online. The adaptation scheme is simple and universal in the ... [more ▼] We present a high-gain observer for nonlinear uniformly observable SISO systems for which the high-gain parameter is determined adaptively online. The adaptation scheme is simple and universal in the sense that it is independent of the system the observer is designed for. Unlike in an earlier approach, the gain is adapted continuously in the present paper. This further simplifies the adaptation law and also leads to lower values of the high-gain parameter. We prove that the observer output error becomes smaller than a user specified bound for large times and that the adaptation converges. The observer is applied to a generic bioreactor [less ▲] Detailed reference viewed: 59 (2 ULg)An adaptive high-gain observer for nonlinear systems Bullinger, Eric ; in 36th IEEE Conf. on Decision and Control (1997) In this paper we present a high-gain observer for a general class of nonlinear SISO systems for which the high-gain parameter is determined on-line in an adaptive fashion. The adaptation scheme is simple ... [more ▼] In this paper we present a high-gain observer for a general class of nonlinear SISO systems for which the high-gain parameter is determined on-line in an adaptive fashion. The adaptation scheme is simple and universal in the sense that it is independent of the system the observer is designed for. We prove that the observer output error becomes smaller than a user specified bound for large times and that the adaptation converges. The assumptions required for the adaptive high-gain observer are the same as for the nonadaptive high-gain observer, namely that the system is uniformly observable for any u(t) [less ▲] Detailed reference viewed: 52 (2 ULg)Application of non-stationary iterative methods to an exact Newton-Raphson solution process for power flow equations ; Bullinger, Eric in 12th Power Systems Computation Conference (1996) AC power flow problems are usually solved by the Newton-Raphson solution method. The main step is the linearization of the nonlinear power flow equations and the subsequent solution of this linear system ... [more ▼] AC power flow problems are usually solved by the Newton-Raphson solution method. The main step is the linearization of the nonlinear power flow equations and the subsequent solution of this linear system. The characteristics of this linear system of equations vary for different power flow implementations; symmetric/unsymmetric, positive definite/indefinite system matrices can result. Based on these characteristics, different direct and iterative linear system solvers can be used to maximize performance and solution robustness. In this paper, results are given of nonstationary iterative methods for unsymmetric, indefinite linear systems derived from power flow equations [less ▲] Detailed reference viewed: 62 (0 ULg) |
||