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dynamics and stability analysis of unbalance responses in mid-positioned electrically assisted turbocharger rotor

International Journal of Mechanical system dynamics 2024年第4期4卷 515-535页

作者： Mingyue Hu Shuqian Cao Xiaolin Cao Zhiyong Zhang Rixiu Men Zhenzhen You Tianyou Wang School of Mechanical Engineering Tianjin UniversityTianjinChina Tianjin Key Laboratory of Nonlinear Dynamics and Control TianjinChina National Key Laboratory of Vehicle Power System TianjinChina Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research InstituteTianjinChina

Electrically assisted turbochargers(EAT)improve intake efficiency by motor-assisted compressor impeller rotation,enhancing the system's transient ***,the addition of motor rotor components has increased the number of unbalanced positions in the shaft system,leading to problems such as excessive compressor end vibration and complex changes in oil film *** evaluate the effects of unbalance in the motor rotor,along with the parameters of floating ring bearings(FRB),on the dynamic response of EAT,a finite element model of an EAT rotor supported by nonlinear FRB is developed,and the vibration response of the compressor end bearing is obtained by numerical *** results indicate:(1)In contrast to the effect of compressor and turbine unbalance,proper motor rotor unbalance is more effective in suppressing oil whirl instability in the high-speed operating ***,a new inner oil film whirl“instability interval”is also induced in the low-speed operating range,leading to an increase in the Y1 compressor-end amplitude at low and medium speeds,and this“instability interval”increases with the amount of unbalance.(2)When an oil whirl occurs in the oil film,the maximum eccentricity of the bearing surges and is greater than 0.3,which can be used as an effective threshold for determining whether the oil film is unstable in engineering applications.(3)A suitable outer oil-film clearance range should be 35–40μm,otherwise,a wide range of outer oil-film whirl instability *** the amount of unbalance and oil-film clearance to suppress the subsynchronous vibration of the EAT,provides a theoretical basis for the design of the dynamics of the nonlinear rotor bearing system and improves the stability of the turbocharger's operation.

关键词： electrically assisted turbocharger motor unbalance oil-film clearance rotor dynamics nonlinear vibration

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Estimating Mutual Information for Link Adaptation in Generalized Spatial Modulation systems with Neural Networks 26

Estimating Mutual Information for Link Adaptation in General...

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26th International ITG Workshop on Smart Antennas, WSA 2023 and 13th Conference on systems, Communications, and Coding, SCC 2023

作者： Bailon, Daniel Nicolas Kühn, Volker Shavgulidze, Sergo Freudenberger, Jürgen Institute for System Dynamics HTWG Konstanz University of Applied Sciences Germany Institute of Communications Engineering Faculty of Computer Science and Electrical Engineering University of Rostock Germany Faculty of Informatics and Control Systems Georgian Technical University Georgia Germany

ISBN: (纸本)9783800760510

Spatial modulation (SM) is a low-complexity multiple-input/multiple-output transmission technique that combines index modulation and quadrature amplitude modulation for wireless communications. In this work, we consider the problem of link adaption for generalized spatial modulation (GSM) systems that use multiple active transmit antennas simultaneously. Link adaption algorithms require a real-time estimation of the link quality of the time-variant communication channels, e.g., by means of estimating the mutual information. However, determining the mutual information of SM is challenging because no closed-form expressions have been found so far. Recently, multilayer feedforward neural networks were applied to compute the achievable rate of an index modulation link. However, only a small SM system with two transmit and two receive antennas was considered. In this work, we consider a similar approach but investigate larger GSM systems with multiple active antennas. We analyze the portions of mutual information related to antenna selection and the IQ modulation processes, which depend on the GSM variant and the signal constellation. © VDE VERLAG GMBH · Berlin · Offenbach.

关键词： Complex networks

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Nodes2STRNet for structural dense displacement recognition by deformable mesh model and motion representation

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International Journal of Mechanical system dynamics 2023年第3期3卷 229-250页

作者： Jin Zhao Hui Li Yang Xu Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbinChina Key Lab of Structures Dynamics Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbinChina School of Civil Engineering Harbin Institute of TechnologyHarbinChina Department of System Design and Simulation Goldwind Science and Technology Co.Ltd.BeijingChina

Displacement is a critical indicator for mechanical systems and civil *** vision-based displacement recognition methods mainly focus on the sparse identification of limited measurement points,and the motion representation of an entire structure is very *** study proposes a novel Nodes2STRNet for structural dense displacement recognition using a handful of structural control nodes based on a deformable structural three-dimensional mesh model,which consists of control node estimation subnetwork(NodesEstimate)and pose parameter recognition subnetwork(Nodes2PoseNet).NodesEstimate calculates the dense optical flow field based on FlowNet 2.0 and generates structural control node ***2PoseNet uses structural control node coordinates as input and regresses structural pose parameters by a multilayer perceptron.A self-supervised learning strategy is designed with a mean square error loss and L2 regularization to train *** effectiveness and accuracy of dense displacement recognition and robustness to light condition variations are validated by seismic shaking table tests of a four-story-building *** studies with image-segmentation-based Structure-PoseNet show that the proposed Nodes2STRNet can achieve higher accuracy and better robustness against light condition *** addition,NodesEstimate does not require retraining when faced with new scenarios,and Nodes2PoseNet has high self-supervised training efficiency with only a few control nodes instead of fully supervised pixel-level segmentation.

关键词： structural dense displacement recognition deformable structural mesh model deep-learning-based monocular vision self-supervised learning

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Neural network aided reference voltage adaptation for NAND flash memory 12

Neural network aided reference voltage adaptation for NAND f...

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12th IEEE International Conference on Consumer Electronics, ICCE-Berlin 2022

作者： Bailon, Daniel Nicolas Taburet, Guillaume Shavgulidze, Sergo Freudenberger, Jurgen HTWG Konstanz University of Applied Sciences Institute for System Dynamics Germany ENSICAEN Engineering School France Georgian Technical University Faculty of Informatics and Control Systems Georgia

ISBN: (数字)9781665456760

ISBN: (纸本)9781665456760

Large persistent memory is crucial for many applications in embedded systems and automotive computing like AI databases, ADAS, and cutting-edge infotainment systems. Such applications require reliable NAND flash memories made for harsh automotive conditions. However, due to high memory densities and production tolerances, the error probability of NAND flash memories has risen. As the number of program/erase cycles and the data retention times increase, non-volatile NAND flash memories' performance and dependability suffer. The read reference voltages of the flash cells vary due to these aging processes. In this work, we consider the issue of reference voltage adaption. The considered estimation procedure uses shallow neural networks to estimate the read reference voltages for different life-cycle conditions with the help of histogram measurements. We demonstrate that the training data for the neural networks can be enhanced by using shifted histograms, i.e., a training of the neural networks is possible based on a few measurements of some extreme points used as training data. The trained neural networks generalize well for other life-cycle conditions. © 2022 IEEE.

关键词： Life cycle

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Construction of Solutions to a Boundary Value Problem with Singularity for a Nonlinear Parabolic system

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Journal of Applied and Industrial Mathematics 2021年第4期15卷 616-626页

作者： Kazakov, A.L. Kuznetsov, P.A. Spevak, L.F. Matrosov Institute for System Dynamics and Control Theory Irkutsk664033 Russia Institute of Engineering Science Ekaterinburg620049 Russia Ural State University of Railway Transport Ekaterinburg620034 Russia

Abstract: We consider a system of two nonlinear second-order parabolic equations with *** of this type are applied in chemical kinetics to describe reaction-diffusion processes. Weprove the existence and uniqueness theorem of an analytic solution having the diffusion-wave typeat a given wave front. The proof is constructive, and the solution had the form of a power serieswith recursively calculated coefficients. Moreover, we propose some numerical algorithm based onthe boundary element method whose verification uses the segments of analytic solutions. © 2021, Pleiades Publishing, Ltd.

关键词： Boundary element method

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Dynamic modeling and analysis of the looped space tether transportation system based on ANCF

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International Journal of Mechanical system dynamics 2022年第2期2卷 204-213页

作者： Jie Yang Qingtao Wang Zhiyong Zhang Zhendong Liu Shidong Xu Gangqiang Li School of Science Nanjing University of Science and TechnologyNanjingChina Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingChina Shanghai Aerospace System Engineering Institute ShanghaiChina State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjingChina Department of Mechanical Engineering York UniversityTorontoCanada

A high‐fidelity multibody‐system dynamic model of the looped tether transportation system(L‐TTS)is proposed in this study to study its large deformation as well as large overall *** absolute nodal coordinate formulation(ANCF)‐based gradient‐deficient beam element is employed to establish the accurate model of the two flexible tethers subject to large *** relative movement of climbers along tethers is described by using the sliding joint model based on *** reduce the collision risks between tethers and climbers,two libration suppression strategies,namely,the decelerated motion of climbers relative to tethers and multiple climbers per tether are investigated in this *** numerical simulations not only validate the effectiveness of the two strategies in reducing the collision risks between climbers and tethers,the overall librations of L‐TTS,and the magnitudes of the longitudinal elastic force of tethers,but also verify the good performance of the high‐fidelity model proposed in this study for dynamic simulation of the L‐TTS in microgravity conditions.

关键词： looped tether transportation system high‐fidelity model absolute nodal coordinate formulation sliding joints libration suppression

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A Modified Iterative Learning control Approach for the Active Suppression of Rotor Vibration Induced by Coupled Unbalance and Misalignment

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Chinese Journal of Mechanical engineering 2024年第1期37卷 242-253页

作者： Yifan Bao Jianfei Yao Fabrizio Scarpa Yan Li College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of High-end Compressor and System Technology Beijing 100029China Beijing Key Laboratory of High-end Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Bristol Composites Institute(ACCIS) University of BristolBristol BS81TRUK Dynamics and Control Research Group(DCRG) University of BristolBristol BS81TRUK

This paper proposes a modified iterative learning control(MILC)periodical feedback-feedforward algorithm to reduce the vibration of a rotor caused by coupled unbalance and parallel *** control of the vibration of the rotor is provided by an active magnetic actuator(AMA).The iterative gain of the MILC algorithm here presented has a self-adjustment based on the magnitude of the *** filters are adopted to extract the synchronous(1×Ω)and twice rotational frequency(2×Ω)components of the rotor *** the notch frequency of the filter and the size of feedforward storage used during the experiment have a real-time adaptation to the rotational *** method proposed in this work can provide effective suppression of the vibration of the rotor in case of sudden changes or fluctuations of the rotor *** and experiments using the MILC algorithm proposed here are carried out and give evidence to the feasibility and robustness of the technique proposed.

关键词： Rotor vibration suppression Modified iterative learning control Unbalance Parallel misalignment Active magnetic actuator

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Design and Evaluation of Nonlinear Inversion Based Automated Landing control for an Airliner in a High Crosswind Scenario

Design and Evaluation of Nonlinear Inversion Based Automated...

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AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Kim, Ho Joong Lombaerts, Thomas Looye, Gertjan Department of Aerospace Engineering San José State University Santa Clara County San JoseCA95121 United States Aerospace Engineering Department Charles W. Davidson College of Engineering United States KBR NASA Ames Research Center Intelligent Systems Division Mail Stop 269-1 Moffett FieldCA94083 United States Institute of System Dynamics and Control German Aerospace Center DLR Weßling82234 Germany

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

This paper describes the design and evaluation of an autoflight controller under maximized crosswind landing scenarios using Nonlinear Dynamic Inversion (NDI) and Incremental Nonlinear Dynamic Inversion (INDI) control methods. The simulation model is representative of a nonlinear, 6 DOF twin-engined civilian transport aircraft in landing configuration starting 300 meters above the runway. The designed flight controller is of cascaded control structure based upon the time scale separation principle. While only INDI based design is evaluated, each control loop implements both NDI and INDI based design, accompanied with feed forward path control for select loops. The controller is evaluated through multiple Monte Carlo statistical analyses, each set containing 2000 landings, which are performed under widely distributed environmental and system parameters. The designed INDI method based controller as discussed in this paper satisfies all safe landing criteria for crosswind landings of up to 30 knots. © 2025, American institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Aircraft landing

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Experimental verification of an online traction parameter identification method

arXiv

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arXiv 2023年

作者： Kobelski, Alexander Osinenko, Pavel Streif, Stefan Technische Universität Chemnitz Automatic Control and System Dynamics Laboratory Germany Skolkovo Institute of Science and Technology Computational and Data Science and Engineering Center Moscow Russia

Traction parameters, that characterize the ground-wheel contact dynamics, are the central factor in the energy efficiency of vehicles. To optimize fuel consumption, reduce wear of tires, increase productivity etc., knowledge of current traction parameters is unavoidable. Unfortunately, these parameters are difficult to measure and require expensive force and torque sensors. An alternative way is to use system identification to determine them. In this work, we validate such a method in field experiments with a mobile robot. The method is based on an adaptive Kalman filter. We show how it estimates the traction parameters online, during the motion on the field, and compare them to their values determined via a 6-directional force-torque sensor installed for verification. Data of adhesion slip ratio curves is recorded and compared to curves from literature for additional validation of the method. The results can establish a foundation for a number of optimal traction methods. © 2023, CC BY-NC-ND.

关键词： Parameter estimation

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Quantized Deep Neural Network Based Optimal control of Greenhouses on a Microcontroller

Quantized Deep Neural Network Based Optimal Control of Green...

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European control Conference (ECC)

作者： Kiran Kumar Sathyanarayanan Philipp Sauerteig Pablo Zometa Stefan Streif Automatic Control and System Dynamics Lab Technische Universität Chemnitz Chemnitz Germany Faculty of Engineering German International University Berlin Germany Department of Bioresources Fraunhofer Institute for Molecular Biology and Applied Ecology Giessen Germany

ISBN: (数字)9783907144107

ISBN: (纸本)9798331540920

Growing crops in controlled-Environment Agriculture (CEA) farms, such as greenhouses and vertical farms, can help in meeting the demands of urban centers and achieving climate goals. Recently, many advanced control techniques like Model Predictive control (MPC) and its variants have been developed for energy-efficient operation and minimization of resource utilization. However, real-time implementation of these advanced strategies come along with certain computational hardware requirements, thus, increasing the operating costs. In this work, we propose to learn the MPC policy of a greenhouse control by means of a Deep Neural Network (DNN) in order to be implemented on a low-cost microcontroller. Additionally, we use a feedback law to reduce undesired quantization effects. The efficiency of our approach is exemplified by means of a simulation study for greenhouse control.

关键词： Quantization (signal) Microcontrollers Optimal control Greenhouses Artificial neural networks Minimization Real-time systems

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