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Applicability of magnetic hysteresis models for predicting the behaviour of MR dampers 9

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Applicability of magnetic hysteresis models for predicting t...

9th ECCOMAS Thematic Conference on Smart Structures and Materials, SMART 2019

作者： Goldasz, J. Sapinski, B. Jastrzebski, L. Kubik, M. Faculty of Electrical Engineering and Computer Science Cracow University of Technology ul. Warszawska 24 Krakow31-155 Poland BWI Technical Center BWI Group ul. Podgorki Tynieckie 2 Krakow30-399 Poland Department of Process Control AGH University of Science and Technology Al. Mickiewicza 30 Krakow30-059 Poland Faculty of Mechanical Engineering Brno University of Technology Technicka 2869/2 Brno616 69 Czech Republic

ISBN: (纸本)9788494919466

This study concerns modeling the magnetic hysteretic behaviour of magnetorheological (MR) dampers. Magnetic hysteresis is one of factors influencing the output of such actuators. The origin of magnetic hysteresis in the actuator’s output is obvious - it is the inherent property of ferromagnetic materials which form the electromagnet’s assembly of the actuator. Prior work on solenoid actuators indicates that hysteresis plays a major role in the flux generation mechanism, and it should be accounted for in the controls development process. So far less attention has been paid to studying the contribution of magnetic hysteresis on the output of MR dampers. Majority of studies on the hysteretic behaviour of MR dampers have virtually neglected that specific contributor. Instead, the hysteretic behaviour of MR actuators was studied by observing the relationships between the output (force/torque) and the inputs (current, velocity, position). Instead, in the present study we separate the magnetic hysteresis from the mechanical/hydraulic one by investigating the magnetic flux vs exciting current relationship of an exemplary MR damper subjected to sinusoidal current (voltage) loading. The resulting behaviour of the electromagnets is then examined using the nonlinear inductor approach with hysteresis. The performance of several hysteretic operators is then evaluated based on their ability to reproduce the magnetic flux output of the MR actuator. © 2019 9th ECCOMAS Thematic Conference on Smart Structures and Materials, SMART 2019. All rights reserved.

关键词： Damping

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Preface

CEUR Workshop Proceedings 2021年 2965卷

作者： Tarassov, Valery Borisov, Vadim Kobrinskii, Boris Bauman Moscow State Technical University Moscow Russia Branch of the National Research University "Moscow Power Engineering Institute" in Smolensk Smolensk Russia Federal Research Center "Computer Science and Control" RAS Moscow Russia

An Improved Ant Colony Optimization Algorithm Based on Fractional Order Memory for Traveling Salesman Problems

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An Improved Ant Colony Optimization Algorithm Based on Fract...

IEEE Symposium Series on Computational Intelligence (SSCI)

作者： Xiaoling Gong Ziheng Rong Tao Gao Yifei Pu Jian Wang College of Control Science and Engineering China University of Petroleum (East China) Qingdao China College of Science China University of Petroleum (East China) Qingdao China College of Computer Science Sichuan University Chengdu China

ISBN: (数字)9781728124858

ISBN: (纸本)9781728124865

Ant Colony Optimization (ACO) algorithm has a wide array of applications to solve combinatorial optimization problems, especially Traveling Salesman Problems (TSPs). The major limitations of ACO algorithm are premature convergence, the possibility that trapped in the local optima. In this paper, an improved Ant Colony Optimization algorithm is proposed which uses fractional order difference for pheromone updating and a weighted combined transition probability. The fractional order difference with the characteristic of long-term memory helps the algorithm make full use of the historical information, and the combined transition probability enhances the exploration ability of the algorithm by using the information of a few steps forward. The performance of the proposed algorithm is tested on various data sets from the standard TSP Library compared with the corresponding integer order algorithm and some evolutionary algorithms. According to the empirical results, our algorithm based on fractional order difference overcomes the classic integer order. Furthermore, the results on a number of TSP instances demonstrate that compared with other evolutionary algorithms, the proposed method can obtain the better solutions on most instances with stronger robustness.

关键词： Urban areas Optimization Signal processing algorithms Fractional calculus Heuristic algorithms Ant colony optimization Traveling salesman problems

Comparing relaxation mechanisms in quantum and classical transverse-field annealing

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arXiv 2020年

作者： Albash, Tameem Marshall, Jeffrey Department of Electrical and Computer Engineering University of New Mexico AlbuquerqueNM87131 United States Department of Physics and Astronomy Center for Quantum Information and Control CQuIC University of New Mexico AlbuquerqueNM87131 United States QuAIL NASA Ames Research Center Moffett FieldCA94035 United States USRA Research Institute for Advanced Computer Science Mountain ViewCA94043 United States

Annealing schedule control provides new opportunities to better understand the manner and mechanisms by which putative quantum annealers operate. By appropriately modifying the annealing schedule to include a pause (keeping the Hamiltonian fixed) for a period of time, we show it is possible to more directly probe the dissipative dynamics of the system at intermediate points along the anneal and examine thermal relaxation rates, for example, by observing the re-population of the ground state after the minimum spectral gap. We provide a detailed comparison of experiments from a D-Wave device, simulations of the quantum adiabatic master equation and a classical analogue of quantum annealing, spin-vector Monte Carlo, and we observe qualitative agreement, showing that the characteristic increase in success probability when pausing is not a uniquely quantum phenomena. We find that the relaxation in our system is dominated by a single time-scale, which allows us to give a simple condition for when we can expect pausing to improve the time-to-solution, the relevant metric for classical optimization. In the system studied here, only for short pauses is there expected to be an improvement. Finally, we also explore in simulation the role of temperature whilst pausing as a means to better distinguish quantum and classical models of quantum annealers. Copyright © 2020, The Authors. All rights reserved.

关键词： Annealing

Path planning for autonomous bus driving in urban environments

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arXiv 2019年

作者： Oliveira, Rui Lima, Pedro F. Pereira, Goncalo Collares Martensson, Jonas Wahlberg, Bo Department of Automatic Control School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Stockholm Sweden Scania Autonomous Transport Solutions Sodertalje Sweden

Driving in urban environments often presents difficult situations that require expert maneuvering of a vehicle. These situations become even more challenging when considering large vehicles, such as buses. We present a path planning framework that addresses the demanding driving task of buses in urban areas. The approach is formulated as an optimization problem using the road-aligned vehicle model. The road-aligned frame introduces a distortion on the vehicle body and obstacles, motivating the development of novel approximations that capture this distortion. These approximations allow for the formulation of safe and nonconservative collision avoidance constraints. Unlike other path planning approaches, our method exploits curbs and other sweepable regions, which a bus must often sweep over in order to manage certain maneuvers. Furthermore, it takes full advantage of the particular characteristics of buses, namely the overhangs, an elevated part of the vehicle chassis, that can sweep over curbs. Simulations are presented, showing the applicability and benefits of the proposed method. Copyright © 2019, The Authors. All rights reserved.

关键词： Motion planning

Multi-agent deployment under the leader displacement measurement: A PDE-based approach

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arXiv 2019年

作者： Wei, Jieqiang Fridman, Emilia Selivanov, Anton Johansson, Karl H. Department of Automatic Control School of Electrical Engineering and Computer Science KTH Royal Institute of Technology StockholmSE-100 44 Sweden School of Electrical Engineering Tel Aviv University Israel

We study the deployment of a first-order multiagent system over a desired smooth curve in 3D space. We assume that the agents have access to the local information of the desired curve and their displacements with respect to their closest neighbors, whereas in addition a leader is able to measure his absolute displacement with respect to the desired curve. In this paper we consider the case that the desired curve is a closed C2 curve and we assume that the leader transmit his measurement to other agents through a communication network. We start the algorithm with displacement-based formation control protocol. Connections from this ODE model to a PDE model (heat equation), which can be seen as a reduced model, are then established. The resulting closed-loop system is modeled as a heat equation with delay (due to the communication). The boundary condition is periodic since the desired curve is closed. By choosing appropriate controller gains (the diffusion coefficient and the gain multiplying the leader state), we can achieve any desired decay rate provided the delay is small enough. The advantage of our approach is in the simplicity of the control law and the conditions. Numerical example illustrates the efficiency of the method. Copyright © 2019, The Authors. All rights reserved.

关键词： Partial differential equations

A pre-allocation design for cost minimization and delay constraint in vehicular offloading system

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arXiv 2019年

作者： Chen, Zhijie Yang, Bo Chen, Cailian Guan, Xinping Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai China Key Laboratory of System Control and Information Processing Ministry of Education of China China

To accommodate exponentially increasing traffic demands of vehicle-based applications, operators are utilizing offloading as a promising technique to improve quality of service (QoS), which gives rise to the application of Mobile Edge Computing (MEC). While the conventional offloading paradigms focus on delay and energy tradeoff, they either fail to find efficient models to represent delay, especially the queueing delay, or underestimate the role of MEC Server. In this paper, we propose a novel Pre-Allocation Design for vehicular Offloading (PADO). A task delay queue is constructed based on an allocate-execute separate (AES) mechanism. Due to the dynamics of vehicular network, we are inspired to utilize Lyapunov optimization to minimize the execution cost of each vehicle and guarantee task delay. The MEC Server with energy harvesting devices is also taken into consideration of the system. The transaction between vehicles and server is decided by a Stackelberg Game framework. We conduct extensive experiments to show the property and superiority of our proposed framework. Copyright © 2019, The Authors. All rights reserved.

关键词： Energy harvesting

Learning structured twin-incoherent twin-projective latent dictionary pairsfor classification

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arXiv 2019年

作者： Zhang, Zhao Sun, Yulin Zhang, Zheng Wang, Yang Liu, Guangcan Wang, Meng School of Computer Science and Technology Soochow University Suzhou215006 China Hefei University of Technology School of Computer Science and Information Engineering Hefei University of Technology Hefei China Shenzhen China School of Information and Control Nanjing University of Information Science and Technology Nanjing China

In this paper, we extendthe popular dictionary pair learning (DPL) into the scenario of twin-projective latent flexible DPL under a structured ***, a novel framework called Twin-Projective Latent Flexible DPL(TP-DPL) is proposed, which minimizes the twin-incoherence constrained flexibly-relaxed reconstruction errorto avoid the possible over-fitting issue and produce accurate reconstruction. In this setting, our TP-DPL integrates the twin-incoherence based latent flexible DPLand the joint embedding of codesas well assalient features by twin-projection into a unified model in an adaptive neighborhood-preserving manner. As a result, TP-DPL unifies the salient feature extraction, representation and classification. The twin-incoherence constrainton codesand features can explicitly ensure high intra-class compactness and inter-class separation overthem. TP-DPL also integrates the adaptive weighting to preserve the local neighborhood of the coefficientsand salient features with in each class explicitly. For efficiency, TP-DPL uses Frobenius-normand abandonsthe costly l0/l1-norm for group sparse representation. Another byproductis that TP-DPL can directly apply the class-specific twin-projective reconstruction residualto computethe label of data. Extensive results on publicdatabases show that TP-DPL can deliver the state-of-the-art performance. Copyright © 2019, The Authors. All rights reserved.

关键词： Machine learning

Secure Distributed Filtering for Unstable Dynamics Under Compromised Observations

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Secure Distributed Filtering for Unstable Dynamics Under Com...

IEEE Annual Conference on Decision and control

作者： Xingkang He Xiaoqiang Ren Henrik Sandberg Karl H. Johansson Division of Decision and Control Systems School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Sweden Department of Automation Shanghai University Shanghai China

ISBN: (数字)9781728113982

ISBN: (纸本)9781728113999

In this paper, we consider a secure distributed filtering problem for linear time-invariant systems with bounded noises and unstable dynamics under compromised observations. A malicious attacker is able to compromise a subset of the agents and manipulate the observations arbitrarily. We first propose a recursive distributed filter consisting of two parts at each time. The first part employs a saturation-like scheme, which gives a small gain if the innovation is too large. The second part is a consensus operation of state estimates among neighboring agents. A sufficient condition is then established for the boundedness of estimation error, which is with respect to network topology, system structure, and the maximal compromised agent subset. We further provide an equivalent statement, which connects to 2s-sparse observability in the centralized framework in certain scenarios, such that the sufficient condition is feasible. Numerical simulations are finally provided to illustrate the developed results.

关键词： Observability Estimation error Technological innovation control systems State estimation Robustness