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Robust adaptive Model Tracking for Distributed Parameter control of Linear Infinite-dimensional Systems in Hilbert Space

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IEEE/CAA Journal of Automatica Sinica 2014年第3期1卷 294-301页

作者： Mark J.Balas Susan A.Frost the Embry-Riddle Aeronautical University the NASA Ames Research Center

This paper is focused on adaptively controlling a linear infinite-dimensional system to track a finite-dimensional reference *** a linear continuous-time infinite-dimensional plant on a Hilbert space with disturbances of known waveform but unknown amplitude and phase,we show that there exists a stabilizing direct model reference adaptive control law with the properties of certain disturbance rejection and *** plant is described by a closed,densely defined linear operator that generates a continuous semigroup of bounded operators on the Hilbert space of *** central result will show that all errors will converge to a prescribed neighborhood of zero in an infinitedimensional Hilbert *** result will not require the use of the standard Barbalat’s lemma which requires certain signals to be uniformly *** result is used to determine conditions under which a linear infinite-dimensional system can be directly adaptively controlled to follow a reference *** particular,we examine conditions for a set of ideal trajectories to exist for the tracking *** results are applied to adaptive control of general linear diffusion systems described by self-adjoint operators with compact resolvent.

关键词： Adaptation models adaptive control Hilbert space Learning (artificial intelligence) Robustness Trajectory adaptive control algorithm adaptive theory distributed parameter system Distributed parameter systems Hilbert space trajectory Adaptation models reference model adaptive control Robustness Computer algorithms

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Remote FxLMS algorithm for Active control of Sound in Remote Locations

Remote FxLMS Algorithm for Active Control of Sound in Remote...

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Annual Summit and Conference of Asia-Pacific-Signal-and-Information-Processing-Association (APSIPA)

作者： Ardekani, Iman Tabatabaei Abdulla, Waleed H. Rehman, Saeed Ur UNITEC Inst Technol Dept Comp Auckland New Zealand Univ Auckland Elect & Comp Engn Dept Auckland New Zealand

ISBN: (纸本)9786163618238

Available adaptive control algorithms can only create a silent point at the locations of an error microphone. In this case, the error microphone occupies a part of the zone of quiet established around the silent point, resulting in an ineffective use of space in the zone of quiet. This paper develops a novel adaptive control algorithm for active control of sound in remote locations rather than the locations of error microphones. It establishes a link between the performance of the FxLMS adaptive algorithm in the digital control domain and the performance of the active noise control mechanism in the acoustic domain. The transfer function of an optimal controller that can minimize the acoustic pressure in a location away from the error microphone is first derived. For the realization of the proposed controller, an adaptive algorithm, called Remote FxLMS is then developed. Different computer simulations are used to show the efficiency of the proposed algorithm.

关键词： active noise control adaptive control digital control least mean squares methods microphones optimal control acoustic domain acoustic pressure active noise control mechanism active sound control adaptive control algorithm adaptive control algorithms computer simulations digital control domain error microphone locations filtered-x least mean square algorithm optimal controller performance analysis quiet zone remote FxLMS adaptive algorithm remote locations silent point transfer function Acoustics Computer simulation control systems Microphones Noise Signal processing algorithms Transfer functions

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adaptive Glide Slope control for Parafoil and Payload Aircraft

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JOURNAL OF GUIDANCE control AND DYNAMICS 2013年第4期36卷 1019-1034页

作者： Ward, Michael Costello, Mark Georgia Inst Technol Guggenheim Sch Aerosp Engn Atlanta GA 30332 USA Georgia Inst Technol Guggenheim Sch Aerosp Engn Woodruff Sch Mech Engn Atlanta GA 30332 USA

The invention of the steerable, gliding, ram-air parafoil enabled the possibility of precision, autonomous aerial payload delivery. Research and development work on guided airdrop systems has focused primarily on evolutionary improvements to the guidance algorithm, although the navigation and control algorithms have changed little since the initial autonomous systems were developed. Recent work has demonstrated the potential for dramatic improvements in landing accuracy through the incorporation of canopy incidence variation to achieve glide slope control for parafoils. The current work presents the development of a control law to implement glide slope control on an autonomous airdrop system. Autonomous landings with the control law in both simulation and flight test demonstrate an improvement in landing accuracy by a factor of two, though the improvement can be even greater in especially windy conditions. Finally, the ability to perform in-flight system identification to adapt internal control mappings to match flight data and provide dramatic improvements in landing accuracy when there is a significant discrepancy between the assumed and actual flight characteristics is demonstrated in both simulation and flight test.

关键词： Parafoil Air Vehicle Flight Test Programme adaptive control algorithm control algorithm Flight Software Navigation algorithm Autonomous Systems Airspeed GPS

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adaptive control OF THE ELECTRO-HYDRAULIC SERVO-SYSTEM WITH EXTERNAL DISTURBANCES

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ASIAN JOURNAL OF control 2013年第4期15卷 1065-1080页

作者： Wos, Piotr Dindorf, Ryszard Kielce Univ Technol PL-23314 Kielce Poland

The paper deals with the structure of the adaptive control electro-hydraulic servo-system (EHSS) with external load disturbances, practical verification of the identification, and control algorithms. The electro-hydraulic servo system composed of a servo-cylinder controlled with a servo-valve is discussed. It is a strongly nonlinear object with parameters changing over time. adaptive adjuster parameters were determined by means of current identification resulting in the parametric model. Identification was conducted on the basis of measurement of the controlling size and regulated size objects. The identified model of the object was applied to carry out the on-line synthesis of the proportional-integral-derivative (PID) controller. The selected problems connected with obtaining the algorithm of adaptive control are presented. The computer program for implementing the algorithm with numerical simulation and identification of the control physical model object were calculated. The aim of the research was to examine the effectiveness of the adaptive control method in an electro-hydraulic servo system, both theoretically and experimentally.

关键词： Electro-hydraulic servo-system system identification adaptive control algorithm forgetting adaptive control

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Variable-Speed IGBT Gate Driver with Loss/Overshoot Balancing for Switching Loss Reduction

Variable-Speed IGBT Gate Driver with Loss/Overshoot Balancin...

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IEEE Energy Conversion Congress and Exposition

作者： Alexey Sokolov Diego Mascarella Geza Joos Department of Electrical & Computer Engineering McGill University Montreal Canada

ISBN: (纸本)9781479957774

This paper introduces a new method of IGBT switching loss reduction on the system level, while leaving the PWM scheme completely unchanged. The switching loss reduction is achieved by designing an IGBT gate driver that dynamically sets the IGBT gate current depending on feedback signals from IGBT current, IGBT voltage, phase load current, and DC link voltage if it is not constant in the application. Factors influencing switching losses will be demonstrated for two types of output driver stages: one with discrete switching speed setting and one with continuously variable switching speed. Comparing to other gate driver types with or without feedback aimed at keeping constant dv/dt, di/dt, and overshoots of IGBT voltage and current, the proposed gate driver not only ensures the operation of an IGBT in the safe operating area (SOA), but also improves the SOA utilization density by tracking the programmed voltage and current limits using peak-detection circuitry while minimizing the switching losses. adaptive feedback control algorithms have been developed and verified by simulations.

关键词： gate driver variable current output stage IGBT switching loss adaptive control algorithm

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adaptive Reaction less Motion and Parameter Identification in Postcapture of Space Debris

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JOURNAL OF GUIDANCE control AND DYNAMICS 2013年第2期36卷 404-414页

作者： Thai Chau Nguyen-Huynh Sharf, Inna McGill Univ Dept Mech Engn Montreal PQ H3A 2K6 Canada

This paper presents a new control scheme for the problem of a space manipulator after capturing an unknown target, such as space debris. The changes in the dynamics parameters of the system, as a result of capturing an unknown target, must be accommodated because they may lead to poor performance of the trajectory control and attitude stabilization system. To address this issue in the postcapture scenario, the adaptive reactionless control algorithm to produce the arm motions with minimum disturbance to the base is proposed in this study. In addition, the online momentum-based estimation method is developed for inertia-parameter identification after the space manipulator grasps an unknown tumbling target with unknown angular momentum. This control scheme is intended for use in the transition phase from the instant of capture until the unknown parameters are identified and/or the available stabilization methods can be applied properly. To verify the validity and feasibility of the proposed concept, *** simulation platform is employed to implement a planar base manipulator target model and the three-dimensional model of the Engineering Test Satellite VII system. The numerical results show that the space manipulator is able to perform reactionless motion while the inertial parameters converge to their real values.

关键词： Orbital Debris Serial Link Manipulators Space Manipulator Attitude control System Satellites control algorithm adaptive control algorithm Three Degrees of Freedom Reaction Wheels Robots

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Neural Network Based Modified State Observer for Orbit Uncertainty Estimation

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JOURNAL OF GUIDANCE control AND DYNAMICS 2013年第4期36卷 1194-1209页

作者： Harl, Nathan Rajagopal, Karthikeyan Balakrishnan, S. N. IST Rolla Rolla MO 65401 USA IST Rolla Dept Mech & Aerosp Engn Rolla MO 65401 USA

A novel technique for estimating uncertainties caused by gravitational perturbations is presented. The approach, called the modified state observer, allows for the estimation of uncertainties in nonlinear dynamics and, in addition, providing estimates of the system states. The observer structure contains neural networks whose outputs are the uncertainties in the system. A useful and important application of this observer is the problem of determining uncertain gravitational perturbations that a satellite may experience when orbiting a body. With future space missions involving other bodies, such as asteroids that produce gravitational perturbations which are highly uncertain and are subjected to unknown physical influences, the modified state observer can be used not only to estimate the states of the satellites, but it can also be used to estimate the uncertainties that could be analyzed further with understanding the physical phenomena. To demonstrate the utility of the modified state observer for this class of problem the technique is applied for two cases: estimating the uncertainty caused by the J(2) perturbation for an Earth orbiter and estimating the uncertainty in an asteroid's gravitational field. Simulations are presented, which indicate that the observer can accurately estimate both the periodic nature of these perturbations, as well as the magnitudes.

关键词： Radial Basis Function Network Asteroids Earth Satellites Nonlinear Dynamics Asteroid Missions Orbiting Body Extended Kalman Filter adaptive control algorithm Monte Carlo Simulation

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Opportunities of adaptive control algorithms Application in Railway control Systems 7

Opportunities of Adaptive Control Algorithms Application in ...

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7th International Conference on Intelligent Technologies in Logistics and Mechatronics Systems (ITELMS 2012)

作者： Potapovs, A. Gorobetz, M. Levehenkov, A. Riga Tech Univ Inst Ind Elect & Elect Engn LV-1658 Riga Latvia

ISBN: (纸本)6090205710

The authors of the article on the example of a particular crossing suggest a description of a new project of adaptive control system of railway crossings work selecting for the adaptive system the most suitable adaptive control algorithm defining its main blocks, their functions, and operation algorithms. At the beginning of the paper the essence of complex objects control adaptation is analysed, and the most optimal one is selected from them. Then the main blocks of the suggested system and their operation are described applying the selected adaptive functioning algorithm. The paper is completed with the comparison of the effectiveness of the suggested system with the present one, proving that the suggested system can significantly compete and solve the problems with traffic in the movement of railway and sity transport.

关键词： railway transport embedded systems adaptive control algorithm

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Multibody Simulation of Integrated Tiltrotor Flight Mechanics, Aeroelasticity, and control

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JOURNAL OF GUIDANCE control AND DYNAMICS 2012年第5期35卷 1391-1405页

作者： Mattaboni, Mattia Masarati, Pierangelo Quaranta, Giuseppe Mantegazza, Paolo Politecn Milan Dipartimento Ingn Aerosp I-20156 Milan Italy

This work describes the application of an adaptive control algorithm based on the generalized predictive control paradigm to a detailed nonlinear aeroelastic model of a tiltrotor aircraft that includes rigid-body degrees of freedom, restricted to the plane of symmetry. The analysis is based on an original multibody dynamics formulation. The model is augmented by an autopilot and a stability augmentation system;in relevant cases, a model of the passive biomechanics of the pilot is considered as well. The interaction of rigid-body and deformable degrees of freedom alters the aeroelastic behavior of the system compared with that of the clamped wing rotor, discussed in a previous work. The flutter mechanism, originally consisting in whirl flutter, changes after considering rigid-body degrees of freedom;the short-period flight mechanics mode now dominates high-speed stability. This issue is mainly addressed by the stability augmentation system, whereas the generalized predictive control is mainly used to reduce gust-induced wing loads, although its intervention for whirl-flutter suppression is still needed to extend the flight envelope at very high speed. The capability of the adaptive regulator RI reduce wing loads is assessed in hover and in highspeed forward flight. In the latter condition, the capability to suppress whirl flutter is assessed as well.

关键词： Flight Mechanics Aeroservoelastic Systems Tiltrotor Aircraft Multibody Simulation Stability and control Augmentation System Autopilot Pilot adaptive control algorithm Flight Envelope Wing Loading

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Online Dynamic Trim and control Limit Estimation

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JOURNAL OF GUIDANCE control AND DYNAMICS 2012年第5期35卷 1647-1656页

作者： Yavrucuk, Ilkay Prasad, J. V. R. Middle E Tech Univ Dept Aerosp Engn TR-06531 Ankara Turkey Georgia Inst Technol Sch Aerosp Engn Atlanta GA 30332 USA

The online estimation of a maneuvering steady-state condition of an aircraft, called the dynamic trim, is used to estimate the allowable control travel during flight, a key information in pilot cueing for envelope limit protection. In this paper a new methodology is presented where adaptive models are used to estimate online local dynamic trim conditions, while requiring very limited a priori vehicle information. adaptive neural networks are employed to enable online learning. The models are used to estimate future aircraft responses and artificial margins on controls that would keep the aircraft response within its flight envelope limits. A linear helicopter model and the XV-15 tiltrotor model are used to demonstrate the method in simulation.

关键词： Neural Networks Pilot Flight Envelope Rotorcrafts Helicopters Flight control System adaptive control algorithm Flight Testing Cyclic control Single Input Single Output System

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