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Optimal control design for uncertain aerial manipulator system based on an adaptive approach

INTERNATIONAL JOURNAL OF AUTOMATION AND CONTROL 2024年第4期18卷 425-443页

作者： Riache, Samah Kidouche, Madjid Doghmane, Mohamed Zinelabidine Tee, Kong Fah Univ Mhamed Bougara Fac Hydrocarbons & Chem Dept Elect Engn Boumerdes Algeria Univ Mhamed Bougara Fac Technol Dept Elect Engn Boumerdes Algeria SONATRACH Explorat Div Hassi Messaoud Algeria King Fahd Univ Petr & Minerals Dept Civil & Environm Engn Dhahran 31261 Saudi Arabia

In this paper, an optimal controller has been proposed for an aerial manipulator (AM) consisting of a quadrotor uncertain system with a two-degrees-of-freedom robotic arm. Wherein, the dynamics of this system have been derived based on Gauss's principle. The employment of this principal has permitted the pinpoint of the inner structure of the uncertain system and its possible moves. It has kept the AM in a very precise formation to analyse its dynamics and propose the suitable control. The proposed controller is designed using an adaptive approach of the non-singular terminal sliding mode technique. The main contribution is that the proposed approach guarantees both the good tracking of the desired trajectories in finite time and the chattering effect attenuation without overestimating the switching control gains. The design does not necessitate a priori knowledge of the upper limits of disturbances;the stability of the system has been established through the utilisation of Lyapunov theory. The simulation results have proved the effectiveness and robustness of the proposed optimal nonlinear terminal sliding mode technique for such an uncertain system in comparison to the sliding mode controller.

关键词： adaptive algorithm chattering quadrotor sliding mode control disturbances

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Recursive adaptive filtering algorithms for sparse channel identification and acoustic noise reduction

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ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING 2023年第1期114卷 51-73页

作者： Bendoumia, Redha Hassani, Islam Guessoum, Abderrezak Univ Blida 1 Detect Informat & Commun Lab DIC Dept Elect Blida Algeria Univ Blida 1 Signal Proc & Image Lab LATSI Dept Elect Blida Algeria

This study addresses impulse response identification and acoustic noise cancellation problems using recursive blind source separation (BSS) techniques based sparse adaptive filtering algorithms. The two-channel adaptive filtering feedback algorithms have been proposed to resolve two problems of noise reduction and speech enhancement when the acoustical mixing system is characterized by dispersive impulse responses. In this paper, three recent NLMS-based sparse adaptive filtering algorithms are implemented on two-channel feedback BSS structures. To evaluate their convergence speed property, we use system mismatch and segmental mean square error criteria. We also use the segmental signal-to-noise ratio and cepstral distance criteria to validate the performance of the presented algorithms in noise reduction and speech enhancement properties. We also have tested these sparse recursive versions with real-life speech signals in various noisy conditions. The obtained results show the good performances of these algorithms compared with the non-sparse versions.

关键词： Sparse impulse response adaptive algorithm Mean square error Proportionate algorithm Cepstral distance

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A multi-satellite co-tracking method for a single space target based on adaptive distributed spherical simplex information-weighted consensus filter

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ADVANCES IN SPACE RESEARCH 2023年第6期71卷 2640-2655页

作者： Hua, Bing Yang, Guang Wu, Yunhua Chen, Zhiming Nanjing Univ Aeronaut & Astronaut Coll Astronaut 29 Gen St Nanjing Jiangsu Peoples R China Nanjing Univ Aeronaut & Astronaut Minist Ind & Informat Technol Key Lab Space Photoelect Detect & Percept 29 Gen St Nanjing Jiangsu Peoples R China Nanjing Univ Aeronaut & Astronaut Coll Astronaut Nanjing 211106 Peoples R China

A multi-satellite co-tracking method for a single non-cooperative target is proposed to extend the arc of observation as well as to improve the accuracy of tracking. Firstly, the motion of the target is considered to be affected by J2 perturbation, and the model of multi-satellite co-tracking a single space target is designed with only measured angles. Then, a multi-satellite co-tracking method for a single space target based on an adaptive distributed spherical simplex information-weighted consensus filter (ADSSICF) is proposed. The spherical simplex is used to reduce the computational cost of the information filter, and to improve the efficiency of tracking. The angle-only measurement equation is linearized by the statistical linear regression method, and linearization errors are compensated for by updating measurement noise. By designing an adaptive consensus algorithm, only a small number of iterations are needed to achieve network consensus, to improve the convergence speed of the consensus algorithm, and prove the stability of ADSSICF. Finally, a sim-ulation of four low-orbit satellites tracking a single space target is established. The focus of this paper is on the real-time performance and tracking accuracy of the multi-satellite co-tracking a single space target with angle-only based on ADSSICF. The performance of ADSSICF is verified from three indicators: the consensus and convergence of algorithm, the accuracy of state estimation.(c) 2022 COSPAR. Published by Elsevier B.V. All rights reserved.

关键词： Non-cooperative target Information filter adaptive algorithm

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An asymmetric-square-wave voltage injection method for online inductance identification of PMSM under sensorless control

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ENERGY REPORTS 2023年 9卷 168-174页

作者： Ge, Yang Song, Weizhang Xian Univ Technol Sch Elect Engn Xian 710048 Peoples R China

In this paper, an online inductance identification method for PMSM, which is embedded into the flux-estimation-based sensorless control, is proposed. By injecting a periodic voltage where a larger negative voltage lasts one switching cycle, and a smaller positive voltage lasts several switching cycles, the extra voltage equation is established. Then, the q-axis current can be decomposed to an asymmetric triangular wave component and a low frequency component. Using the triangular wave current and the voltage equation, an inductance identification algorithm is designed. Since the injected positive voltage can be smaller, this method overcomes the difficulty that the symmetric square wave voltage cannot be injected at high-speed range, thus expanding the application of the inductance identification. And since the triangular wave current can be accurately extracted, the interference caused by back-EMF is eliminated. The simulation results demonstrate the effectiveness of the method.(c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://***/licenses/by/4.0/).

关键词： PMSM Sensorless control Asymmetric-square-wave voltage injection Inductance identification adaptive algorithm

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Self-Aware Social Learning Over Graphs

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IEEE TRANSACTIONS ON INFORMATION THEORY 2023年第8期69卷 5299-5317页

作者： Ntemos, Konstantinos Bordignon, Virginia Vlaski, Stefan Sayed, Ali H. Univ Basel Ctr Data Analyt CeDA CH-4056 Basel Switzerland Ecole Polytech Fed Lausanne EPFL Sch Engn CH-1015 Lausanne Switzerland Imperial Coll London London SW7 2BX England

In this paper we study the problem of social learning under multiple true hypotheses and self-interested agents that exchange information over a graph. In this setup, each agent receives data that might be generated from a different hypothesis (or state) than the data received by the other agents. In contrast to the related literature on social learning, which focuses on showing that the network achieves consensus, here we study the case where every agent is self-interested and wishes to find the hypothesis that generates its own observations. Moreover, agents do not know which other agents among their peers want to discover the same state as theirs. As a result they do not know which agents they should cooperate with. To enable learning under these conditions, we propose a strategy with adaptive combination weights and study the consistency of the agents' learning process. The method allows each agent to identify and collaborate with neighbors that observe the same hypothesis, while excluding others, thus resulting in improved performance compared to both non-cooperative learning and cooperative social learning solutions. We analyze the asymptotic behavior of agents' beliefs and provide conditions that enable all agents to correctly identify their true hypotheses. The theoretical analysis is corroborated by numerical simulations.

关键词： Social learning self-interested agents information diffusion adaptive algorithm

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An Enhanced Impulse Noise Control algorithm Using a Novel Nonlinear Function

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CIRCUITS SYSTEMS AND SIGNAL PROCESSING 2023年第11期42卷 6524-6543页

作者： Cheng, Yabing Li, Chao Chen, Shuming Zhou, Zhengdao Jilin Univ Sch Mech & Aerosp Engn Changchun 130022 Peoples R China Jilin Univ State Key Lab Automot Simulat & Control Changchun 130022 Peoples R China Jilin Univ Chongqing Res Inst Chongqing 401123 Peoples R China

In many scenarios where impulse noise occurs, an active noise control (ANC) system using a filtered-x least mean square (FxLMS) algorithm will have undesirable effects. To solve this problem, a novel adaptive algorithm is proposed that takes the Gaussian error function as the cost function to nonlinearly transform the residual error. To attenuate the different levels of impulse noise, the parameter k is used as a factor that transforms the error signal by different degrees. To further improve the efficiency of the algorithm, we propose a variable step size strategy based on normalized variable step size, combined with the sine function. Not only the random impulse noise signals generated by the Chambers-Mallows-Stuck method are adopted for simulation, but also the noise signals collected from real vehicles are used in this work. Finally, the simulations are carried out and the results show that the proposed algorithm offers perfect performance in dealing with different levels of impulse noise.

关键词： Impulse noise control adaptive algorithm Nonlinear error transformation Variable step size strategy

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Improved Dynamic Geometry Control algorithms for Efficient Aerodynamic Shape Optimization

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AIAA JOURNAL 2023年第5期61卷 2116-2134页

作者： Streuber, Gregg M. M. Zingg, David W. Univ Toronto Inst Aerosp Studies Toronto ON M3H 5T6 Canada Univ Toronto Inst Aerosp Studies Computat Aerodynam & Sustainable Aviat Toronto ON M3H 5T6 Canada Univ Toronto Ctr Res Sustainable Aviat Toronto ON M3H 5T6 Canada

In aerodynamic shape optimization, traditional static geometry control methods can produce suboptimal performance by introducing performance tradeoffs at various stages of optimization, enforcing arbitrary constraints on open-ended optimization, and necessitating foreknowledge of problem behavior to design an effective control scheme. These shortcomings can be mitigated through dynamic geometry control, which partly automates the geometry control design process by refining the geometry control topology throughout optimization. Such refinement can occur in a predetermined fashion (as in progressive control) or more automatically using sensitivity information to guide refinement (as in adaptive control). Both progressive control and adaptive control are implemented in the context of axial and free-form deformation geometry control, and novel contributions are made to the adaptive algorithm, including the treatment of active constraints and several novel "potential indicators" to rank candidate refinements. Application to a wide suite of aerodynamic shape optimization problems demonstrates that dynamic geometry control is effective, producing lower final drag than well-designed static schemes while reducing required iterations to convergence by 50% or more, and simultaneously reducing labor requirements on the user. These benefits are demonstrated across a wide variety of problems, representative of detailed and exploratory problems often encountered in both academia and industry.

关键词： Aerodynamic Shape Optimization algorithms and Data Structures adaptive algorithm adaptive Control Broyden Fletcher Goldfarb Shanno Aircraft Components and Structure Reynolds Averaged Navier Stokes Transonic Flow Optimal Control Theory Aircraft Design

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Maximizing the stable throughput of heterogeneous nodes under airtime fairness in a CSMA environment

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COMPUTER COMMUNICATIONS 2023年第1期210卷 229-242页

作者： Baiocchi, Andrea Univ Roma Sapienza DIET Via Eudossiana 18 I-00184 Rome Italy

The stability region of non-persistent CSMA is analyzed in a general heterogeneous network, where stations have different mean packet arrival rates, packet transmission times probability distributions and transmission probabilities. The considered model of CSMA captures the behavior of the well known CSMA/CA, at least as far as stability and throughput evaluation are concerned. The analysis is done both with and without collision detection. Given the characterization of the stability region, throughput-optimal transmission probabilities are identified under airtime fairness, establishing asymptotic upper and lower bounds of the maximum achievable stable throughput. The bounds turn out to be insensitive to the probability distribution of packet transmission times. Numerical results highlight that the obtained bounds are tight not only asymptotically, but also for essentially all values of the number of stations. The insight gained leads to the definition of a distributed adaptive algorithm to adjust the transmission probabilities of stations so as to attain the maximum stable throughput.

关键词： CSMA Stability Airtime fairness Throughput optimization adaptive algorithm

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The adaptive SAV weak Galerkin finite element method for the Allen-Cahn equation

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COMPUTERS & MATHEMATICS WITH APPLICATIONS 2023年 151卷 449-460页

作者： Liu, Ying Shen, Xiaoqin Guan, Zhen Nie, Yufeng Xian Univ Technol Sch Sci Dept Math Xian 710048 Shaanxi Peoples R China Pingdingshan Univ Sch Math & Stat Pingdingshan 467000 Henan Peoples R China Northwestern Polytech Univ Sch Math & Stat Xian 710129 Shaanxi Peoples R China

In this paper, the weak Galerkin finite element method with the scalar auxiliary variable (SAV) approach is considered for the Allen-Cahn equation. Based on the elliptic reconstruction technique, the elliptic equation corresponding to the Allen-Cahn equation is introduced, which is employed to split the numerical error into the elliptic error and the parabolic error. Then the weak gradient recovery type a posteriori error estimator of the elliptic equation is adopted to develop the time-space adaptive algorithm. The effectiveness of the SAV weak Galerkin finite element method and the time-space adaptive algorithm is verified by several numerical benchmarks on both uniform and adaptive meshes.

关键词： Weak Galerkin finite element method SAV approach Elliptic reconstruction adaptive algorithm

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Dual-variable-horizon peridynamics and continuum mechanics coupling modeling and adaptive fracture simulation in porous materials

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ENGINEERING WITH COMPUTERS 2023年第5期39卷 3207-3227页

作者： Shen Shangkun Yang Zihao Cui Junzhi Zhang Jieqiong Northwestern Polytech Univ Sch Math & Stat Xian 710072 Peoples R China Chinese Acad Sci Acad Math & Syst Sci LSEC ICMSEC Beijing 100190 Peoples R China Northwest Univ Sch Math Xian 710127 Peoples R China

In this paper, we present a hybrid dual-variable-horizon peridynamics/continuum mechanics modeling approach and a strength-induced adaptive coupling algorithm to simulate brittle fractures in porous materials. Peridynamics theory is promising for fracture simulation since it allows discontinuities in the displacement field. However, they remain computationally expensive. Besides, there exists the surface effect in peridynamics due to the incomplete neighborhoods near the boundaries, including the outer boundaries and the boundaries of inner pores in porous materials. The proposed approach couples continuum mechanics and peridynamics into a closed equation system and an adaptive algorithm is developed to activate the peridynamics according to a strength criterion. In addition, the surface effect is corrected by introducing an improved peridynamic model with dual and variable horizons. We conduct the simulations using the relevant discretization scheme in each domain, i.e., the discontinuous Galerkin finite-element in the peridynamic domain and the continuous finite-element in the continuum mechanics domain. Two-dimensional numerical examples illustrate that successful fracture simulations of random porous materials can be achieved by this approach. In addition, the impact of distribution and size of pores on the fractures of porous materials is also investigated.

关键词： Porous materials Peridynamics Surface correction Hybrid model adaptive algorithm Fracture simulation

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