The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Dennis S. Bernstein - One of the best experts on this subject based on the ideXlab platform.
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Nonlinear Feedback control with global stabilization
Dynamics and Control, 1995Co-Authors: Chih-jian Wan, Dennis S. BernsteinAbstract:Hamilton-Jacobi-Bellman theory is shown to provide a unified framework for Nonlinear Feedback control laws for special classes of Nonlinear systems. These classes include Jurdjevic-Quinn type systems, as well as minimum phase systems with relative degree {1, 1, ..., 1}. Several examples are given to illustrate these results. For the controlled Lorenz equation, results obtained by Vincent and Yu are extended. Next, for spacecraft angular velocity stabilization with two torque inputs, a family of Nonlinear Feedback control laws that globally asymptotically stabilize angular velocity is established. Special cases of this family of control laws include generalizations of the locally stabilizing control laws of Brockett and Aeyels to global stabilization as well as the globally stabilizing control laws of Irving and Crouch and Byrnes and Isidori. Finally, the results are applied to spacecraft angular velocity stabilization with only one torque input. These last results extend control laws given by Outbib and Sallet.
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Nonquadratic cost and Nonlinear Feedback control
International Journal of Robust and Nonlinear Control, 1993Co-Authors: Dennis S. BernsteinAbstract:Nonlinear controllers offer significant advantages over linear controllers in a variety of circumstances. Hence there has been significant interest in extending linear-quadratic synthesis to Nonlinear-nonquadratic problems. The purpose of this paper is to review the current status of such efforts and to present, in a simplified and tutorial manner, some of the basic ideas underlying these results. Our approach focuses on the role of the Lyapunov function in guaranteeing stability for autonomous systems on an infinite horizon. Sufficient conditions for optimality are given in a form that corresponds to a steady-state version of the Hamilton-Jacobi-Bellman equation. These results are used to provide a simplified derivation of the Nonlinear Feedback controller obtained by Bass and Webber (1966)38 and to obtain a deterministic variation of the stochastic Nonlinear Feedback controller developed by Speyer (1976).45.
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Nonquadratic Cost and Nonlinear Feedback Control
1991 American Control Conference, 1991Co-Authors: Dennis S. BernsteinAbstract:Nonlinear controllers offer significant advantages over linear controllers in a variety of circumstances. Hence there has been significant interest in extending linear-quadratic synthesis to Nonlinear-nonquadratic problems. The purpose of this paper is to review the current status of such efforts and to present, in a simplified manner, some of the basic ideas underlying these results. Our approach focusses on the role of the Lyapunov function in guaranteeing stability for autonomous systems on an infinite horison. Sufficient conditions for optimality are given in a form that corresponds to a steady-state Hamilton-Jacobi-Bellman equation. These results are used to provide a simplified derivation of the Nonlinear Feedback controller obtained by Bass and Webber (1966) and to obtain a deterministic variation of the stochastic Nonlinear Feedback controller developed by Speyar (1976).
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A family of optimal Nonlinear Feedback controllers that globally stabilize angular velocity
[1992] Proceedings of the 31st IEEE Conference on Decision and Control, 1Co-Authors: Chih-jian Wan, Dennis S. BernsteinAbstract:Hamilton-Jacobi-Bellman theory is used to derive optimal Nonlinear Feedback control laws for a special class of Nonlinear systems. The results are applied to a spacecraft angular velocity stabilization problem with two torque inputs. A family of optimal Nonlinear Feedback controllers that globally asymptotically stabilize angular velocity is established. Special cases of this family of controllers include generalizations of the locally stabilizing controllers of Brockett and Aeyels to global stabilization as well as the globally stabilizing controller of Byrnes and Isidori. >
Antal K. Bejczy - One of the best experts on this subject based on the ideXlab platform.
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ICRA - Experimental evaluation of the Nonlinear Feedback robot controller
Proceedings. 1991 IEEE International Conference on Robotics and Automation, 1Co-Authors: Tzyh Jong Tarn, S. Ganguly, A.k. Ramadorai, G.t. Marth, Antal K. BejczyAbstract:The trajectory tracking performance of the Nonlinear Feedback controller based on differential geometric control theory was experimentally studied. The performance is compared to three other methods: independent joint proportional-derivative (PD) control, independent joint PD control with feedforward torque computations, and the computed torque method. In the Nonlinear Feedback controller, servo is in the task space. In the other three methods servo is in the joint space. Path planning is in the task space. Circular and straight line paths are considered. A sampling frequency of 200 Hz is used. The effect of sampling frequency on tracking error is studied for the Nonlinear Feedback control scheme. The performance of these methods was tested on a PUMA 560 arm. The trajectory tracking performance of the robot arm under the Nonlinear Feedback controller is comparable to that of the computed torque control schemes. >
Valiollah Ghaffari - One of the best experts on this subject based on the ideXlab platform.
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Optimal tuning of composite Nonlinear Feedback control in time-delay Nonlinear systems
Journal of the Franklin Institute, 2020Co-Authors: Valiollah GhaffariAbstract:Abstract A composite Nonlinear Feedback tracking control is mainly designed via the linear matrix inequality approach in the time-delay Nonlinear systems. For achieving this purpose, the composite Nonlinear Feedback control design is firstly formulated in the Nonlinear systems with time-delay. Then, a sufficient stability condition will be addressed in terms of the linear matrix inequality feasibility checking. Therefore, a stabilizing composite Nonlinear Feedback control policy can be obtained with solving of the linear matrix inequality. A quadratic cost function is considered as a performance index for optimal tuning of the composite Nonlinear Feedback control. A minimization problem subject to some linear matrix inequality constraints would be subsequently suggested to the composite Nonlinear Feedback control tuning. The proposed control method is numerically simulated in two time-delay dynamical systems. The effectiveness of the suggested control law will be shown in comparing with the existing control techniques.
Guanrong Chen - One of the best experts on this subject based on the ideXlab platform.
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A necessary and sufficient condition for right coprime factorization of Nonlinear Feedback systems
Circuits Systems and Signal Processing, 1993Co-Authors: Robert Danow, Guanrong ChenAbstract:In this short note, we establish a simple, yet precise, necessary and sufficient condition for the “right coprime factorization” of a Nonlinear Feedback control system. As a consequence, we also obtain similar conditions for the “stable right coprime factorizations ” of the Nonlinear Feedback control system.
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Hopf bifurcations in time-delayed Nonlinear Feedback control systems
Proceedings of 1995 34th IEEE Conference on Decision and Control, 1Co-Authors: Jorge L. Moiola, Guanrong ChenAbstract:The Hopf bifurcation in a time-delayed Nonlinear closed-loop control system is studied, where the Nonlinear system has a linear dynamic plant represented by a feedforward transfer function and a Nonlinear Feedback controller represented by a Taylor series about an equilibrium operating point. The time delays occurred in the system are contained not only in the linear plant but also in the Nonlinear Feedback controller. The effective harmonic balance method is modified and applied to calculating the amplitude and frequency of the periodic solution emerging from the Hopf bifurcation of the dynamic system. Some new formulas containing up to an eighth-order harmonic balance approximation are derived, and two interesting examples are analyzed using the new results.
Ding Liu - One of the best experts on this subject based on the ideXlab platform.
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Nonlinear Feedback Control of Chaos in Permanent
2006Co-Authors: Haipeng Ren, Ding LiuAbstract:Permanent magnet synchronous motor (PMSM) will demonstrate chaotic phenomena when its parameters fall into a certain area. The performance of PMSM will degrade because of chaos. Therefore, chaos should be suppressed or eliminated. Ac- cording to the features of this practical plant, the drawbacks of existing control methods are analyzed, and the Nonlinear Feedback control method is suggested to control the chaos in PMSM. The Nonlinear Feedback principle is developed using the direct axis and the quadrature axis stator voltage as manipulated variables. The control target will become a unique asymptotically stable equilib- rium under the Nonlinear Feedback principle, by this way, the con- trolled states can reach the target and the control objective can be implemented. This method can be physically realized using non- linear state Feedback. The control forces can be put into effect at any time. The target of the method may be any point in the strange attractor. The influence of the model error and the measurement noise upon the control performance is studied via simulations. Sim- ulation results show the effectiveness of this method under the pres- ence of the model error and the measurement noise.
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Nonlinear Feedback control of chaos in permanent magnet synchronous motor
IEEE Transactions on Circuits and Systems II: Express Briefs, 2006Co-Authors: Haipeng Ren, Ding LiuAbstract:Permanent magnet synchronous motor (PMSM) will demonstrate chaotic phenomena when its parameters fall into a certain area. The performance of PMSM will degrade because of chaos. Therefore, chaos should be suppressed or eliminated. According to the features of this practical plant, the drawbacks of existing control methods are analyzed, and the Nonlinear Feedback control method is suggested to control the chaos in PMSM. The Nonlinear Feedback principle is developed using the direct axis and the quadrature axis stator voltage as manipulated variables. The control target will become a unique asymptotically stable equilibrium under the Nonlinear Feedback principle, by this way, the controlled states can reach the target and the control objective can be implemented. This method can be physically realized using Nonlinear state Feedback. The control forces can be put into effect at any time. The target of the method may be any point in the strange attractor. The influence of the model error and the measurement noise upon the control performance is studied via simulations. Simulation results show the effectiveness of this method under the presence of the model error and the measurement noise
