scholarly journals Adaptive nonlinear optimal control for active suppression of airfoil flutter via a novel neural-network-based controller

2018 ◽  
Vol 24 (22) ◽  
pp. 5261-5272 ◽  
Author(s):  
Difan Tang ◽  
Lei Chen ◽  
Zhao F. Tian ◽  
Eric Hu
Keyword(s):  
Optimal Control ◽  
Nonlinear Systems ◽  
Linear Matrix ◽  
Nonlinear Controller ◽  
Control Laws ◽  
Active Suppression ◽  
Value Function Approximation ◽  
Control Scheme ◽  
New Form ◽  
Hamilton Jacobi Bellman

This paper proposes a novel adaptive nonlinear controller based on neural-networks (NNs) for active suppression of airfoil flutter (ASAF) from the optimal control perspective. Optimal control laws for locally nonlinear systems are synthesized in real time by solving the Hamilton–Jacobi–Bellman equation online with a proposed new form of NN-based value function approximation (VFA) and an extended Kalman filter. A systematic procedure based on linear matrix inequalities is further proposed for designing a scheduled parameter matrix that generalizes the new form of VFA to globally nonlinear systems to suit ASAF applications. Un-modeled dynamics are captured using an NN identifier. Comparisons drawn with a linear-parameter-varying optimal controller in wind-tunnel experiments confirm the effectiveness and validity of the proposed control scheme.

Delayed Output Feedback Control for Nonlinear Systems With Fuzzy Observers

2012 ◽  
Author(s):  
Mansour Karkoub ◽  
Tzu Sung Wu
Keyword(s):  
Feedback Control ◽  
Nonlinear System ◽  
Nonlinear Systems ◽  
Output Feedback ◽  
Tracking Error ◽  
Sufficient Conditions ◽  
Output Feedback Control ◽  
Linear Matrix ◽  
External Disturbances ◽  
Control Scheme

In this paper, the design problem of delayed output feedback control scheme using two-layer interval fuzzy observers for a class of nonlinear systems with state and output delays is investigated. The Takagi-Sugeno type fuzzy linear model with an on-line update law is used to approximate the nonlinear system. Based on the fuzzy model, a two-layer interval fuzzy observer is used to reconstruct the system states according to equal interval output time delay slices. Subsequently, a delayed output feedback adaptive fuzzy controller is developed to override the nonlinearities, time delays, and external disturbances such that the H∞ tracking performance is achieved. The linguistic information is developped by setting the membership functions of the fuzzy logic system and the adaptation parameters to estimate the model uncertainties directly for using linear analytical results instead of estimating nonlinear system functions. The filtered tracking error dynamics are designed to satisfy the Strictly Positive Realness (SPR) condition. Based on the Lyapunov stability criterion and linear matrix inequalities (LMIs), some sufficient conditions are derived so that all states of the system are uniformly ultimately bounded and the effect of the external disturbances on the tracking error can be attenuated to any prescribed level and consequently an H∞ tracking control is achieved. Finally, a numerical example of a two-link robot manipulator is given to illustrate the effectiveness of the proposed control scheme.

scholarly journals Quantum demolition filtering and optimal control of unstable systems

2012 ◽  
Vol 370 (1979) ◽  
pp. 5396-5407 ◽  
Author(s):  
V. P. Belavkin
Keyword(s):  
Optimal Control ◽  
Feedback Control ◽  
Open Loop ◽  
Information Dynamics ◽  
Unstable Systems ◽  
Dissipative Term ◽  
Control Scheme ◽  
Hamilton Jacobi Bellman ◽  
Classical Control ◽  
And Control

A brief account of the quantum information dynamics and dynamical programming methods for optimal control of quantum unstable systems is given to both open loop and feedback control schemes corresponding respectively to deterministic and stochastic semi-Markov dynamics of stable or unstable systems. For the quantum feedback control scheme, we exploit the separation theorem of filtering and control aspects as in the usual case of quantum stable systems with non-demolition observation. This allows us to start with the Belavkin quantum filtering equation generalized to demolition observations and derive the generalized Hamilton–Jacobi–Bellman equation using standard arguments of classical control theory. This is equivalent to a Hamilton–Jacobi equation with an extra linear dissipative term if the control is restricted to Hamiltonian terms in the filtering equation. An unstable controlled qubit is considered as an example throughout the development of the formalism. Finally, we discuss optimum observation strategies to obtain a pure quantum qubit state from a mixed one.

scholarly journals Procedure for forming nominal control program of solar sail spacecraft heliocentric movement using locally optimal control laws

2020 ◽  
Vol 4 (1) ◽  
pp. 5-13
Author(s):  
R. M. Khabibullin
Keyword(s):  
Optimal Control ◽  
Control Program ◽  
Solar Sail ◽  
Flight Trajectory ◽  
Control Laws ◽  
Phase Coordinates ◽  
Control Scheme ◽  
Control Schemes ◽  
Efficient Control ◽  
Interplanetary Flight

The paper is devoted to the non-coplanar interplanetary flight Earth-Venus of the spacecraft equipped with a solar sail. The goal of the heliocentric movement is to transfer a spacecraft with a non-perfectly reflecting solar sail into the Hill’s sphere of the Venus with zero hyperbolic excess speed. The magnitude and direction of acceleration is calculated taking into account specular and diffuse reflections, absorption and transmission of photons by the surface of the solar sail. One of the main tasks in the field of navigation and motion control of a spacecraft is the search for a simple energy-efficient control scheme for performing maneuvers during flight. These control schemes are locally optimal control laws, various combinations of which allow you to perform the necessary maneuvers during an interplanetary flight. The procedure for the formation of a control program for a non-coplanar interplanetary flight of the Earth-Venus type of a spacecraft with a non-perfectly reflecting solar sail is described. The results include the flight trajectory, the change in phase coordinates in time, graphs of changes in control angles, and the nominal control program. The obtained results satisfy all the boundary conditions described in the statement of the problem.

Robust inverse optimal control laws for nonlinear systems

2003 ◽  
Vol 13 (15) ◽  
pp. 1371-1388 ◽  
Author(s):  
Nael H. El-Farra ◽  
Panagiotis D. Christofides
Keyword(s):  
Optimal Control ◽  
Nonlinear Systems ◽  
Inverse Optimal Control ◽  
Control Laws
Sign in / Sign up

Export Citation Format

Share Document