Flutter Suppression of Bridge Deck Section With Controllable Winglets Using Output Feedback

2017 ◽  
Author(s):  
K. K. Bera ◽  
N. K. Chandiramani
Keyword(s):  
Output Feedback ◽  
Bridge Deck ◽  
Output Feedback Control ◽  
Control Input ◽  
Flat Plates ◽  
Maximum Increase ◽  
The Stability ◽  
Control Forces ◽  
And Control ◽  
Direct Feedback

Control of wind induced flutter of a bridge deck is studied using static output feedback. Servomotor actuated winglets provide the control forces. Deck and winglets are modeled as flat plates and their aerodynamic interaction is neglected. Self excited wind forces acting on deck and winglets are modeled using the Scanlan-Tomko model, with flat plate flutter derivatives obtained from Theodorsen functions. Rogers rational function approximation is used for time domain representation of wind forces in order to simplify the stability and control analyses. Control input to servomotors is based on direct feedback of vertical and torsional displacements of deck. Feedback gains that are constant, or varying with wind speed, are considered. Winglet rotations being restricted, flutter and divergence behavior is studied using system eigenvalues as well as responses. Results show that variable gain output feedback control provides the maximum increase in critical speed and also response attenuation, followed by control with gain scheduling. Control with constant gain is least effective.

Bridge Deck Flutter Control Using Winglets and Static Output Feedback

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
K. K. Bera ◽  
N. K. Chandiramani
Keyword(s):  
Wind Speed ◽  
Output Feedback ◽  
Bridge Deck ◽  
Input Power ◽  
Effective Control ◽  
Control Input ◽  
Static Output Feedback ◽  
Flat Plates ◽  
Maximum Increase ◽  
Static Output

Control of wind-induced flutter of a bridge deck is studied using static output feedback. Servomotor-actuated winglets provide the control forces. Deck and winglets are modeled as flat plates and their aerodynamic interaction is neglected. Self-excited wind forces acting on deck and winglets are modeled using the Scanlan–Tomko model, with flat plate flutter derivatives (FDs) obtained from Theodorsen functions. Rogers rational function approximation (RFA) is used for time domain representation of wind forces in order to simplify the stability and control analyses. Control input to servomotors is based on direct feedback of vertical and torsional displacements of deck. Feedback gains that are constant, or varying with wind speed, are considered. Winglet rotations being restricted, flutter and divergence behavior is studied using system eigenvalues as well as responses. Results show that variable gain output feedback (VGOF) control using servomotor driven winglets is very effective. It provides the maximum increase in critical speed and maximum attenuation of response, followed by control with gain scheduling, with the former requiring less input power. Control with constant gain is least effective. Control of deck rotation generally appears to improve with wind speed.

Extended state observer–based output feedback control for spacecraft pose tracking with control input saturation

2021 ◽  
pp. 095441002110177
Author(s):  
Kejie Gong ◽  
Ying Liao ◽  
Yafei Mei
Keyword(s):  
Feedback Control ◽  
Output Feedback ◽  
Finite Time ◽  
Output Feedback Control ◽  
State Observer ◽  
Extended State Observer ◽  
Control Input ◽  
Extended State ◽  
Pose Tracking ◽  
Control Scheme

This article proposed an extended state observer (ESO)–based output feedback control scheme for rigid spacecraft pose tracking without velocity feedback, which accounts for inertial uncertainties, external disturbances, and control input constraints. In this research, the 6-DOF tracking error dynamics is described by the exponential coordinates on SE(3). A novel continuous finite-time ESO is proposed to estimate the velocity information and the compound disturbance, and the estimations are utilized in the control law design. The ESO ensures a finite-time uniform ultimately bounded stability of the observation states, which is proved utilizing the homogeneity method. A non-singular finite-time terminal sliding mode controller based on super-twisting technology is proposed, which would drive spacecraft tracking the desired states. The other two observer-based controllers are also proposed for comparison. The superiorities of the proposed control scheme are demonstrated by theory analyses and numerical simulations.

Three-dimensional adaptive fixed-time guidance law against maneuvering targets with impact angle constraints and control input saturation

2021 ◽  
pp. 014233122110598
Author(s):  
Fei Ma ◽  
Yunjie Wu ◽  
Siqi Wang ◽  
Xiaofei Yang ◽  
Yueyang Hua
Keyword(s):  
Sliding Mode ◽  
Input Saturation ◽  
Three Dimensional ◽  
Fixed Time ◽  
Impact Angle ◽  
Guidance System ◽  
Control Input ◽  
Guidance Law ◽  
The Stability ◽  
And Control

This paper presents an adaptive fixed-time guidance law for the three-dimensional interception guidance problem with impact angle constraints and control input saturation against a maneuvering target. First, a coupled guidance model formulated by the relative motion equation is established. On this basis, a fixed-time disturbance observer is employed to estimate the lumped disturbances. With the help of this estimation technique, the adaptive fixed-time sliding mode guidance law is designed to accomplish accurate interception. The stability of the closed-loop guidance system is proven by the Lyapunov method. Simulation results of different scenarios are executed to validate the effectiveness and superiority of the proposed guidance law.

scholarly journals Vibration Control of Blade Section Based on Sliding Mode PI Tracking Method and OPC Technology

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Tingrui Liu
Keyword(s):  
Vibration Control ◽  
Sliding Mode ◽  
Engineering Application ◽  
Control Input ◽  
Pi Method ◽  
Opc Technology ◽  
Practical Engineering ◽  
Blade Section ◽  
The Stability ◽  
And Control

Vibration control of the blade section of a wind turbine is investigated based on the sliding mode proportional-integral (SM-PI) method, i.e., sliding mode control (SMC) based on a PI controller. The structure is modeled as a 2D pretwisted blade section integrated with calculation of structural damping, which is subjected to flap/lead-lag vibrations of instability. To facilitate the hardware implementation of the control algorithm, the SM-PI method is applied to realize tracking for limited displacements and velocities. The SM-PI algorithm is a novel SMC algorithm based on the nominal model. It combines the effectiveness of the sliding mode algorithm for disturbance control and the stability of PID control for practical engineering application. The SM-PI design and stability analysis are discussed, with superiority and robustness and convergency control demonstrated. An experimental platform based on human-computer interaction using OPC technology is implemented, with position tracking for displacement and control input signal illustrated. The platform verifies the feasibility and effectiveness of the SM-PI algorithm in solving practical engineering problems, with online tuning of PI parameters realized by applying OPC technology.

Global sampled-data output feedback stabilization for a class of switched stochastic nonlinear systems with quantized input and unknown output gain

2019 ◽  
Vol 41 (16) ◽  
pp. 4511-4520
Author(s):  
Yan Jiang ◽  
Junyong Zhai
Keyword(s):  
Nonlinear Systems ◽  
Output Feedback ◽  
Output Feedback Control ◽  
Sampling Period ◽  
Feedback Stabilization ◽  
Design Parameters ◽  
Stochastic Nonlinear Systems ◽  
Control Input ◽  
Sampled Data ◽  
Data Output

This paper aims at addressing the sampled-data output feedback control problem for a class of uncertain switched stochastic nonlinear systems, whose control input is quantized by a logarithmic quantizer and the output gain cannot be precisely known. We design a compensator with the quantized information. With the help of the feedback domination approach and the backstepping design method, a sampled-data output feedback controller is constructed with appropriate design parameters and a maximum sampling period to guarantee the global exponential stability in mean square of the closed-loop system under arbitrary switching. Finally, a numerical example is given to illustrate the effectiveness of the proposed scheme.

Friction Identification Using Evolution Strategies and Robust Control of Positioning Tables

1999 ◽  
Vol 121 (4) ◽  
pp. 619-624 ◽  
Author(s):  
Seon-Woo Lee ◽  
Jong-Hwan Kim
Keyword(s):  
Static Friction ◽  
Velocity Model ◽  
Friction Model ◽  
Evolution Strategies ◽  
Linear Feedback ◽  
Control Input ◽  
Identification Technique ◽  
Friction Identification ◽  
The Stability ◽  
And Control

This paper presents an identification technique using evolution strategies (ES) for an integrated friction model of a positioning table. The friction model is based on Karnopp’s friction-velocity model with the rising static friction and spring-like property. Using the (μ + λ)-ES, the system parameters are identified with the experimental input and output data. The proposed control law consists of a conventional linear feedback control input, a friction compensation term and a sliding control input. The proposed control scheme can guarantee the stability of the overall system, even in the presence of the external disturbances and the modeling error between the real friction and the identified model. Experiments on an positioning table, called X-Y table, demonstrate the effectiveness of the proposed identification and control schemes.

scholarly journals Analysis of Robust Stability for a Class of Stochastic Systems via Output Feedback: The LMI Approach

2013 ◽  
Vol 2013 ◽  
pp. 1-8
Author(s):  
Xin-rong Cong ◽  
Long-suo Li
Keyword(s):  
Linear Matrix Inequality ◽  
Robust Stability ◽  
Output Feedback ◽  
Stochastic Systems ◽  
Linear Matrix ◽  
Matrix Inequality ◽  
Convex Optimization Problem ◽  
Control Laws ◽  
The Stability ◽  
And Control

This paper investigates the robust stability for a class of stochastic systems with both state and control inputs. The problem of the robust stability is solved via static output feedback, and we convert the problem to a constrained convex optimization problem involving linear matrix inequality (LMI). We show how the proposed linear matrix inequality framework can be used to select a quadratic Lyapunov function. The control laws can be produced by assuming the stability of the systems. We verify that all controllers can robustly stabilize the corresponding system. Further, the numerical simulation results verify the theoretical analysis results.

On Selection of Control Parameters for H∞ Output Feedback

2005 ◽  
Author(s):  
Chang-Ching Chang ◽  
Chi-Chang Lin
Keyword(s):  
Control System ◽  
Feedback Control ◽  
Output Feedback ◽  
Delay Time ◽  
Output Feedback Control ◽  
Feedback Gain ◽  
Control Force ◽  
Control Parameters ◽  
Structural Responses ◽  
Control Forces

In this paper, an H∞ direct output feedback control algorithm through minimizing the entropy, a performance index measuring the tradeoff between H∞ optimality and H2 optimality, is employed to design the control system in reducing structural responses due to dynamic loads such as earthquakes. The control forces are obtained from the multiplication of direct output measurements by a pre-calculated time-invariant feedback gain matrix. To achieve optimal control performance, the strategy to select both control parameters γ and α is extensively investigated. The decrease of γ or increase of α results in better control effectiveness, but larger control force requirement. For a single degree-of-freedom (SDOF) damped structure, exact solutions of output feedback gains and control parameters are derived. It can be proved analytically that the LQR control is a special case of the proposed H∞ control. Direct velocity feedback control is effective in reducing structural responses with very small number of sensors and controllers compared with the DOFs of the structure. In active control of a real structure, control force execution time delay cannot be avoided. Relatively small delay time not only can render the control ineffective, but also may cause system instability. In this study, explicit formulas to calculate maximum allowable delay time and critical control parameters are derived for the design of a stable control system. Some solutions are also proposed to increase the maximum allowable delay time.

scholarly journals Decentralized Adaptive Tracking of Interconnected Nonlinear Systems by Corrupted Output Feedback

Mathematics ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 1340
Author(s):  
Dong Min Jeong ◽  
Sung Jin Yoo
Keyword(s):  
Nonlinear Systems ◽  
Output Feedback ◽  
Output Feedback Control ◽  
Feedback Stabilization ◽  
Control Technique ◽  
Control Input ◽  
Measurement Sensitivity ◽  
Control Scheme ◽  
Interconnected Nonlinear Systems ◽  
Output Information

A decentralized adaptive resilient output-feedback stabilization strategy is presented for a class of uncertain interconnected nonlinear systems with unknown time-varying measurement sensitivities. In the concerned problem, the main difficulty is to achieve the decentralization of interconnected output nonlinearities unmatched to the control input by using only local output information corrupted by measurement sensitivity, namely the exact output information cannot be used to design the decentralized output-feedback control scheme. Thus, a decentralized output-feedback stabilizer design using only the corrupted output of each subsystem is developed where the adaptive control technique is employed to compensate for the effects of unknown measurement sensitivities. The stability of the resulting decentralized control scheme is analyzed based on the Lyapunov stability theorem.

Sign in / Sign up

Export Citation Format

Share Document