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Active Global Vibration control of Helicopter Fuselage

AIAA JOURNAL 2023年第8期61卷 3692-3706页

作者： Lang, Kai Xia, Pinqi Wang, Xiao Nanjing Univ Aeronaut & Astronaut Coll Aerosp Engn Natl Key Lab Rotorcraft Aeromech Nanjing 210016 Peoples R China

Active control of structural response (ACSR) has been widely used to suppress helicopter fuselage vibration due to its advantages. However, ACSR, by taking the vibration responses at target measurement points as the active control objective, is a local vibration control method for the fuselage. In this paper, an active global vibration control (AGVC) method for the fuselage by taking the vibratory loads transmitting to the fuselage through gearbox struts as the active control objective is proposed. By installing piezoelectric stack actuators on a gearbox strut, the active strut is formed and its electromechanical coupling equation of motion is derived. The AGVC model, algorithm, convergence, and system for a dynamically similar frame structure of a helicopter fuselage are presented. The simulation results indicate that AGVC can suppress the global vibration of the fuselage under the excitation of the rotor vibratory loads more effectively with faster convergence speed than ACSR. The vibration at the target measurement points in ACSR can be effectively reduced, but the control effect at other positions is not satisfied, and even the vibration at some positions is larger than that in control off.

关键词： Active Vibration control Piezoelectric Actuators control algorithm Vibration Suppression Helicopters control Law Design

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Active control of Aeroelastic Vibrations for Electromechanical Missile Fin Actuation Systems

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JOURNAL OF GUIDANCE control AND DYNAMICS 2017年第12期40卷 3296-3303页

作者： Yoo, Chung-Hee Agcy Def Dev Daejeon 34186 South Korea 1st Res & Dev Inst POB 35 Yuseong South Korea

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Vibration control using fuzzy-logic-based active damping

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JOURNAL OF AIRCRAFT 2003年第2期40卷 384-390页

作者： Cohen, K Ben-Asher, JZ Weller, T Israel Def Forces IL-61909 Tel Aviv Israel Technion Israel Inst Technol Dept Aerosp Engn IL-32000 Haifa Israel

In this study a general approach is introduced for the design of a robust control law for suppression of structure borne vibration. This control law is based on a passive design in the form of dynamic vibration absorbers. Passive absorbers minimize vibration at a specific frequency, but their performance is improved by introducing adaptive tuning of the absorber. An adaptive dynamic vibration absorber is tuned to the forcing frequency, using classical methods. The tuning ratio is time varying and adapts itself to variations in the forcing frequency. However, the uniqueness of the approach in this study is that the damping parameter of the absorber is continuously varied by means of a fuzzy-logic control algorithm to provide a lower sound pressure level. The inputs of:the fuzzy control law are the displacement and velocity of the main structure: The effectiveness of the control algorithm for active vibration control is demonstrated using MATLAB(R) simulations of a single-degree-of-freedom plant. This methodology provides superior performance in the presence of significant mistuning compared to a more conventional approach.

关键词： Active Vibration control Fuzzy control Dynamic Vibration Absorber Linear Time Invariant System Sound Pressure Level control algorithm MATLAB Transport Aircraft Cantilever Beam Numerical Simulation

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Theoretical and experimental research on a new system of semi-active structural control with variable stiffness and damping

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 130-135页

作者：周福霖谭平阎维明魏陆顺 Guangzhou University Guangzhou 510405China Professor Guangzhou University Guangzhou 510405China Lecturer Beijing polytechnic University Beijing 100032 China Professor

In this paper,a new system of semi active structural control with active variable stiffness and damping (AVSD) is *** new system amplifies the structural displacement to dissipate more energy,and in turn,effectively reduces the structural response in the case of relatively small story drifts,which occur during earthquakes.A predictive instantaneous optimal control algorithm is established for a SDOF structure equipped with an AVSD system Comparative shaking table tests of a 1/4 scale single story structural model with a full scale control device have been *** the experimental and analytical results,it is shown that when compared to structures without control or with the active variable stiffness control alone, the suggested system exhibits higher efficiency in controlling the structural response,requires less energy input,operates with higher reliability,and can be manufactured at a lower cost and used in a wider range of engineering applications.

关键词： semi-active structural control variable stiffness and damping control device control algorithm shaking table test

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Proportional closed-loop feedback control of flow separation

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AIAA JOURNAL 2007年第1期45卷 181-190页

作者： Pinier, Jeremy T. Ausseur, Julie M. Glauser, Mark N. Higuchi, Hiroshi Syracuse Univ Dept Aerosp & Mech Engn Syracuse NY 13244 USA

The aim of this experimental study is the implementation of a practical and efficient closed-loop feedback control of the turbulent flow over a NACA-4412 airfoil equipped with leading-edge zero-net-mass-flux actuators. By using prior computation of correlations between particle image velocimetry data and multiple surface pressure measurements, real-time instantaneous low-dimensional estimates of the velocity field over the wing are then computed from the unsteady surface pressure. From such estimates, a direct knowledge of the state of the flow above the airfoil is obtained (i.e., attached, incipient separation, or fully separated flow). We first show the effectiveness of the low-dimensional modeling approach in extracting and estimating the underlying large-scale structures in a turbulent flow, using the proper orthogonal decomposition and the modified linear/quadratic stochastic measurements. We then show how such an approach is used successfully in a simple, but practical, proportional feedback loop to delay the separation of the flow over the wing at high angles of attack. The benefits of closed-loop vs open-loop control are then discussed. These fundamental results validate the use of low-dimensional modeling techniques for further, more sophisticated, closed-loop feedback control algorithms.

关键词： Feedback control Loop Closed Loop control Boundary Layer Separation Piezoelectric Actuators Particle Image Velocimetry NACA 4412 Angle of Attack Compressible Flow Leading Edges control algorithm

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Electrospray Thrusters as Precise Attitude control Actuators for Small Satellites

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JOURNAL OF GUIDANCE control AND DYNAMICS 2017年第3期40卷 642-649页

作者： Mier-Hicks, Fernando Lozano, Paulo C. MIT Dept Aeronaut & Astronaut 77 Massachusetts Ave Cambridge MA 02139 USA

The purpose of this work is to describe the use of electrospray propulsion devices as miniaturized actuators for precise attitude control of small satellites, including CubeSats. Electrosprays are nonpressurized, passively fed, compact and fuel-efficient electric thrusters capable of producing impulse bits in the 10(-6)N s or lower, depending on the configuration. These characteristics have the potential to allow for long-term pointing in the arcsecond range or better with practically no jitter. Experimental work is performed on a magnetically levitated testbed in vacuum to demonstrate the actuation characteristics under nonoptimal control. It is found that, subject to a noisy attitude sensor and external perturbations, electrospray thrusters are capable of producing pointing accuracies around a given set point of 22 arcseconds 3 sigma error during 10h on a platform similar in size and mass to a 1U CubeSat. The implementation of such capabilities could complement or eliminate the need of reaction wheels and magnetorquers, especially in missions beyond low Earth orbit, while including propulsive capabilities for additional maneuverability in technology development or scientific missions.

关键词： Attitude control System Actuators Thrusters Small Satellites Sensor Fusion Reaction Wheels Chemical Propulsion Propellant Power Processing Unit control algorithm

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Robust Nonlinear Close Formation control of Multiple Fixed-Wing Aircraft

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JOURNAL OF GUIDANCE control AND DYNAMICS 2021年第3期44卷 572-586页

作者： Zhang, Qingrui Liu, Hugh H. T. Sun Yat Sen Univ Sch Aeronaut & Astronaut Guangzhou 510006 Peoples R China Univ Toronto Inst Aerosp Studies Toronto ON M3H 5T6 Canada

This paper investigates robust nonlinear control for close formation flight of multiple fixed-wing aircraft. It aims to achieve precise position control in general flight operation under the aerodynamic impact induced by the trailing vortices of leader aircraft. One crucial concern is the boundedness of position errors subject to uncertainties and disturbances to be regulated with accuracy. This paper develops a robust nonlinear control algorithm to fulfill precise close formation-tracking control. The proposed control algorithm consists of baseline control laws and disturbance observers. The baseline control laws are employed to stabilize the nonlinear dynamics of close formation flight, whereas the disturbance observers are introduced to compensate system uncertainties and formation-related aerodynamic disturbances. The position control performance can be guaranteed within the desired boundedness to harvest enough drag reduction for a follower aircraft in close formation using the proposed design. The effectiveness of the proposed design is demonstrated via the numerical simulation of the close formation flight of two fixed-wing aircraft.

关键词： Fixed Wing Aircraft Routh Hurwitz Stability Criterion Aerodynamic Coefficients Nonlinear Dynamics Nonlinear Dynamic Inversion Vortices Numerical Simulation Flight Operation control algorithm Flight Path Angle

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Design and control of a three degree-of-freedom permanent magnet spherical actuator

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SENSORS AND ACTUATORS A-PHYSICAL 2012年 180卷 75-86页

作者： Chen, Weihai Zhang, Liang Yan, Liang Liu, Jingmeng Beihang Univ Sch Automat Sci & Elect Engn Beijing 100191 Peoples R China

This paper presents a permanent magnet (PM) spherical actuator embedded with a novel three-dimensional (3D) orientation measurement system. The study covers actuator design, torque modeling, and motion control. The spherical actuator consists of a stator with 24 coils and a rotor with 8 PM poles. A high accuracy and resolution, non-blinding 3D measurement mechanism is designed for the rotor orientation detection. The torque output is formulated from finite element (FE) computation and curve fitting method. Due to the nonlinear property of dynamic model, computed torque control law is utilized for the three degree-of-freedom (3-DOF) system motion control. The space geometry method is employed to study the redundancy feature of current inputs, which offers the opportunity for control optimization to improve the power efficiency and the fault tolerance capability of the spherical actuator. Simulations and experiments are then conducted on the developed prototype to validate the design concept, mathematic models and control strategy. (C) 2012 Elsevier B.V. All rights reserved.

关键词： Spherical actuator Orientation measurement Torque modeling control algorithm

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Analysis of an interleaved control scheme employed in split source inverter based grid-tied photovoltaic systems

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IET RENEWABLE POWER GENERATION 2021年第6期15卷 1301-1314页

作者： Nannam, Hari Charan Banerjee, Atanu Guerrero, Josep M. Natl Inst Technol Meghalaya Shillong Meghalaya India Aalborg Univ Dept Energy Technol Aalborg Denmark

In conventional grid-tied renewable energy applications, the dc-dc converter is inevitable. An increased cost, size, and reduced efficiency are the demerits of incorporating a dc-dc converter. A recently introduced split source inverter (SSI) is capable to perform both dc-dc as well as dcac at a time. The main attractive controllable feature of SSI is its modulation index. By utilizing this parameter, an interleaved control structure is proposed for the SSI in grid-tied photovoltaic applications. The main objectives of the work are to track peak power and to maintain a stabilized voltage across the dc-link capacitor at a variable load and grid disturbances. The proposed peak power controller performs two important actions: (i) the peak power is traced at all irradiance and (ii) generates a duty cycle to enhance the dc-link capacitor voltage. The proposed scheme is essentially investigated with simulation. To validate experimentally, a 1 KW photovoltaic system is integrated into a grid-tied 10 kVA SSI prototype. A Xilinx based Spartan field-programmable gate array (FPGA) is used to provide a control algorithm for the SSI. Few case studies at different conditions are performed and investigated. Experimental and simulation results are presented to prove the robustness of the control strategy.

关键词： grid-tied renewable energy applications power control xilinx based spartan field-programmable gate array control of electric power systems FPGA Logic and switching circuits peak power controller Logic circuits control algorithm grid disturbances variable load invertors DC-DC power convertors power grids field programmable gate arrays dc-link capacitor voltage Solar power stations and photovoltaic power systems Power and energy control dc-dc converter Voltage control interleaved control structure photovoltaic power systems split source inverter based grid-tied photovoltaic systems renewable energy sources grid-tied 10 kVA SSI prototype photovoltaic system voltage control

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Cooperative circumnavigation control of multiple unicycle-type robots with non-identical input constraints

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IET control THEORY AND APPLICATIONS 2022年第9期16卷 889-901页

作者： Yu, Yangguang Miao, Zhiqiang Wang, Xiangke Shen, Lincheng Natl Univ Def Technol Coll Intelligence Sci & Technol Changsha 410073 Peoples R China Hunan Univ Coll Elect & Informat Engineeting Changsha Peoples R China Natl Engn Lab Robot Visual Petcept & Control Tech Changsha Peoples R China

For the robot control problems, the input constraint is an issue that must be carefully considered. Considering the control inputs of the robots in the multi-robot system are constrained by different saturations in reality, we address the cooperative circumnavigation control problem of multiple unicycle-type robots with non-identical and unknown input constraints in this paper. A distributed control law is designed to drive the robots constrained by different and unknown input saturations to achieve the cooperative circumnavigation around a moving target. The algorithm proposed in this paper largely reduces the requirement for the maneuverability of the robots to achieve the cooperative circumnavigation. As long as the robots owns the basic maneuverability of circumnavigating around the target, it is proved rigorously that the proposed control algorithm can achieve the desired cooperation circumnavigation of the multi-robot system. The effectiveness of the proposed method is validated by a numerical simulation.

关键词： different input saturations distributed control law mobile robots control algorithm unknown input saturations multiple unicycle-type robots desired cooperation circumnavigation multi-robot systems path planning robot control problems nonidentical input constraints numerical analysis different saturations multirobot system control system synthesis circumnavigation control problem unknown input constraints distributed control control inputs input constraint

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