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2022 CSAA/IET International Conference on aircraft Utility Systems, AUS 2022

作者： Liu, Yaoxian Jiao, Zongxia Zhao, Longfei School of Automation Science and Electrical Engineering Beihang University Beijing China Ningbo Institute of Technology Beihang University Ningbo China Science and Technology on Aircraft Control Laboratory Beihang University Beijing China Research Institute for Frontier Science Beihang University Beijing China

ISBN: (数字)9781839537769

ISBN: (纸本)9781839537769

In this paper, a new tandem wing distributed propulsion vertical takeoff and landing configuration is investigated, and the modeling and control assignment of this new configuration is described. Six-degree-of-freedom full-state dynamics modeling and simulation modeling are completed first. A suitable attitude representation is chosen and the analysis starts with the flight characteristics of the tandem-wing vehicle. Based on the flight principle and its force and moment generation mechanism, the dynamics and kinematic equations were studied, and a nonlinear mathematical model was constructed using a suitable method, which laid the foundation for the subsequent control system design verification. Then, on the basis of the constructed model, the derivation of the control efficiency matrix and the study of the control allocation method were completed. The study of control allocation includes the linearization of control actuators, the design of control allocators for transition states and the study and comparative analysis of three allocation strategies: pseudo-inverse, weighted pseudo-inverse and direct allocation methods. © 2022 IET Conference Proceedings. All rights reserved.

关键词： Nonlinear equations

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A Cellular Strategy for Eliminating the Failure of Nonlinear Energy Sinks Under Strong Excitation

A Cellular Strategy for Eliminating the Failure of Nonlinear...

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International Conference on Applied Nonlinear Dynamics, Vibration, and control, ICANDVC 2023

作者： Li, Sun-Biao Ding, Hu School of Mechanics and Engineering Science Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai200444 China Shaoxing Institute of Technology Shanghai University Shaoxing312074 China Shanghai Institute of Aircraft Mechanics and Control Zhangwu Road Shanghai200092 China

ISBN: (纸本)9789819705535

Nonlinear energy sinks (NES) have numerous advantages, such as wide vibration bandwidth and excellent vibration reduction performance. However, under high excitation intensity, its high vibration attenuation effect often becomes ineffective. Therefore, exploring methods to address this issue and broaden their application range remains a subject for further research. This paper investigates the dynamic characteristics of systems composed of linear oscillators and multiple NES cells and studies the vibration reduction effect of NES cells using the Complexifiction-Averaging (CxA) method, and the obtained results were numerically verified using the Runge-Kutta (R-K) method. The results show that when NES cells are present in the form of cells, increasing the number of cells can reduce the system's saddle-node (SN) bifurcation region, especially shrinking the frequency island region produced by the system under strong excitation. When the number of cells reaches a certain value, the frequency island of the system disappears. Additionally, regardless of whether the system generates frequency islands or not, increasing the number of cells generally improves the vibration reduction efficiency of NES cells. Thus, the cellular strategy proposed in this paper effectively addresses the ineffectiveness of traditional NES under strong excitation and expands its application range. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Cells

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Aerodynamic and Powertrain Design of a Novel VTOL Configuration

Aerodynamic and Powertrain Design of a Novel VTOL Configurat...

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2022 CSAA/IET International Conference on aircraft Utility Systems, AUS 2022

作者： Zhao, Runyu Jiao, Zongxia Zhao, Longfei School of Automation Science and Electrical Engineering Beihang University Beijing China Ningbo Institute of Technology Beihang University Ningbo China Science and Technology on Aircraft Control Laboratory Beihang University Beijing China Research Institute for Frontier Science Beihang University Beijing China

ISBN: (数字)9781839537769

ISBN: (纸本)9781839537769

This paper presents aerodynamic and powertrain system design of a new configuration of vertical take-off and landing (VTOL) unmanned aerial vehicles (UAVs). This configuration consists of the tandem wing and distributed motors, which is capable of fast take off at an inclined angle to the ground, adequate maneuverability at low airspeed and strong wind resistance. The aerodynamic design is optimized for maximum lift-drag (LD) ratio using engineering estimation method, which is validated and corrected by Computational Fluid Dynamics (CFD) simulation. A powertrain design tool is established by which the propeller-motor system can reach high efficiency in both the hover mode and the cruise mode. Then three types of powertrain system are optimized and compared. In the end, the best preliminary design is derived with maximum endurance time. © 2022 IET Conference Proceedings. All rights reserved.

关键词： Antennas

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Research On The Flow Characteristics Of The Secondary Regulation aircraft Weapon Bay Door Drive System With Accumulator

Research On The Flow Characteristics Of The Secondary Regula...

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2022 CSAA/IET International Conference on aircraft Utility Systems, AUS 2022

作者： Wang, Zhenyu Liu, Xiaochao Qiu, Zhongyi Jiao, Zongxia School of Automation Science and Electrical Engineering Beihang University Beijing China Ningbo Institute of Technology Beihang University Ningbo China Research Institute for Frontier Science Beihang University Beijing China Science and Technology on Aircraft Control Laboratory Beihang University Beijing China

ISBN: (数字)9781839537769

ISBN: (纸本)9781839537769

The principle of secondary regulation is a common energy-saving driving method in hydraulic system. This paper introduces a secondary regulation hydraulic drive system with accumulator, the accumulator and secondary components are the key components of the system. This paper takes the aircraft weapon bay door drive system as the application target, the simulation model of the whole system is established, and its flow characteristics are analyzed. The results show that, compared with the traditional hydraulic drive system, the secondary regulation hydraulic drive system with accumulator realizes the four quadrant operation of the secondary components by adjusting the inclination of the swashplate, the latter system can match the real-time load under the reverse load condition, avoid the throttling loss, and complete the energy storage under the forward load condition, to reduce the peak flow of the system by more than 80%. The influence of different volume accumulators on the flow characteristics of secondary regulation hydraulic drive system is studied. The research shows that the accumulator volume has an optimal range under the determined load. © 2022 IET Conference Proceedings. All rights reserved.

关键词： aircraft

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NBA-guided heuristic sampling algorithm for multi-robot task planning under temporal logic

NBA-guided heuristic sampling algorithm for multi-robot task...

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第43届中国控制会议

作者： Jiong Luo Yongzhao Hua Shunfu Ding Xiwang Dong Zhang Ren School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control LaboratoryBeihang University Institute of Artificial Intelligence Beihang University Institute of Unmanned System Beihang University

ISBN: (数字)9789887581581

ISBN: (纸本)9798350366907

Aiming at the task planning problem of multi-robot under linear temporal logic(LTL), this paper proposes an improved sampling planning algorithm based on Nondeterministic Büchi automaton(NBA) guidance. Firstly, this paper defines a kind of LTL task planning problem, which mainly focuses on the meaningful key nodes in the task execution of each robot, and there are many sequential dependencies of task constraints. Then, an improved sampling algorithm framework is proposed,which uses a more efficient way to build a search tree and reduces the number of nodes in the tree. Furthermore, the sampling points are guided by NBA to ensure that sampling is conducive to the advancement of time-series tasks. And considering the task feasible region of each robot, the auction algorithm is introduced to optimize the local matching relationship, which greatly improves the quality of sampling points. Finally, numerical simulation is carried out to solve the LTL task planning problem. The optimality and stability of the algorithm are obviously improved, and the time consumption of this algorithm is obviously better than that of the existing advanced algorithms.

关键词： Multi-robot systems sampling-based planning temporal logic task planning NBA-guided

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Output Formation Tracking control for Heterogeneous Multi-Agent Systems with Application to Unmanned Aerial and Ground Vehicles 41

Output Formation Tracking Control for Heterogeneous Multi-Ag...

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第41届中国控制会议

作者： Peixuan Shu Yu Hu Yongzhao Hua Xiwang Dong Zhang Ren School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control LaboratoryBeihang University Shenyuan Honors College Beihang University Beijing Institute of Astronatical Systems Engineering Institute of Artificial Intelligence Beihang University

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

Distributed output formation tracking control problem for heterogeneous multi-agent systems(HMASs) was studied in this *** HMASs include multi-rotor unmanned aerial vehicles(UAVs) and unmanned ground vehicles(UGVs) with nonholonomic constraints.A formation tracking protocol was proposed for the follower UAVs and UGVs to track the virtual leader's output trajectory while keeping a predefined time-varying *** this protocol,a distributed observer was first designed for each follower to estimate the states of the ***,a local formation controller based on feedback linearization was designed for UAVs,while a nonlinear controller was presented for UGVs to tackle the nonholonomic *** effectiveness of this protocol was proved by the Lyapunov stability ***,a cooperative searching experiment with two quadrotors and a wheeled vehicle was performed under the ultra wide band(UWB) positioning system,and the experiment results matched the simulation well.

关键词： Formation tracking control heterogeneous multi-agent systems UAV UGV

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Optimization of Narrow-magnet EMAT for Lamb Waves with Low Distortion

Optimization of Narrow-magnet EMAT for Lamb Waves with Low D...

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Sensor technology and control (ISSTC), International Symposium on

作者： Haifeng Qu Zheng Hu Lishuai Liu Yanxun Xiang Shanghai Key Laboratory of intelligent Sensing and Detection Technology East China University of Science and Technology Shanghai China Shanghai Institute of Aircraft Mechanics and Control Shanghai Key Laboratory of intelligent Sensing and Detection Technology East China University of Science and Technology Shanghai China

ISBN: (数字)9798331541637

ISBN: (纸本)9798331541644

Compared to traditional electromagnetic acoustic transducer (EMAT), the narrow-magnet EMAT extends its meander conductors to the edges and outside of the magnet, hence a wider area of the magnetic field can be used to excite stronger ultrasound waves. Because of the magnetic field inhomogeneity, the classical half-wavelength spacing rule is not suitable for the coil used in the narrow-magnet EMAT. Otherwise, obvious waveform distortions will appear. In this work, the coil conductor spacing correction methodology proposed in previous works is testified for Lamb wave excitations, and a simpler wavelength-based adjustment approach is proposed, where waveforms of low distortions can be obtained. Both approaches are evaluated in simulation and practical experiments, where the Lamb wave amplitude enhancement brought by the coil conductor spacing correction method is more than 157.41%, and the improvement achieved by the proposed wavelength adjustment concept is above 179.34%.

关键词： Coils Acoustic distortion Magnetic field measurement Ultrasonic variables measurement Wavelength measurement Electromagnetic scattering Magnetoacoustic effects Conductors Magnetic fields Electromagnetics

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Lightweight hybrid visual-inertial odometry with closed-form zero velocity update

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Chinese Journal of Aeronautics 2020年第12期33卷 3344-3359页

作者： QIU Xiaochen ZHANG Hai FU Wenxing School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Aircraft Control Laboratory Beijing 100191China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing 100074China

Visual-Inertial Odometry(VIO) fuses measurements from camera and Inertial Measurement Unit(IMU) to achieve accumulative performance that is better than using individual *** VIO is an extended Kalman filter-based solution which augments features with long tracking length into the state vector of Multi-State Constraint Kalman Filter(MSCKF). In this paper, a novel hybrid VIO is proposed, which focuses on utilizing low-cost sensors while also considering both the computational efficiency and positioning precision. The proposed algorithm introduces several novel contributions. Firstly, by deducing an analytical error transition equation, onedimensional inverse depth parametrization is utilized to parametrize the augmented feature *** modification is shown to significantly improve the computational efficiency and numerical robustness, as a result achieving higher precision. Secondly, for better handling of the static scene,a novel closed-form Zero velocity UPda Te(ZUPT) method is proposed. ZUPT is modeled as a measurement update for the filter rather than forbidding propagation roughly, which has the advantage of correcting the overall state through correlation in the filter covariance matrix. Furthermore, online spatial and temporal calibration is also incorporated. Experiments are conducted on both public dataset and real data. The results demonstrate the effectiveness of the proposed solution by showing that its performance is better than the baseline and the state-of-the-art algorithms in terms of both efficiency and precision. A related software is open-sourced to benefit the community.

关键词： Inverse depth parametrization Kalman filter Online calibration Visual-inertial odometry Zero velocity update

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Fade probability simulation analysis for aircraft platform wireless optical communication based on Hermite-Gaussian beam

Fade probability simulation analysis for aircraft platform w...

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2022 International Symposium on Aerospace Engineering and Systems, ISAES 2022

作者： Liu, Xin Zhang, Yu Jiang, Dagang Qin, Kaiyu University of Electronic Science and Technology of China School of Astronautics and Aeronautics Sichuan Chengdu China Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province Sichuan Chengdu China

Wireless optical communication technology can provide larger channel capacity for aircraft platforms which has great potentiality. In the application scenario of aircraft platform, the pointing error is inevitable. This study analyzes the fade probability of the link based on Hermite-Gaussian beam by using single-layer phase screen with pointing error simulation method and comparing with Gaussian beam. The higher order Hermite-Gaussian beam shows better link stability performance. Atmosphere turbulence has obvious effect on fade probability when the standard variance of pointing error is small, with the increase of standard variance of pointing error, the major influence factor for fade probability is pointing error rather than atmosphere turbulence. © Published under licence by IOP Publishing Ltd.

关键词： aircraft

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Uncertainty Quantification of Store-Separation Simulation Due to Ejector Modeling using a Monte Carlo Approach with Kriging Model

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Advances in Applied Mathematics and Mechanics 2022年第3期14卷 622-651页

作者： Shuling Tian Rongjie Li Jiawei Fu Zihan Jiao Jiangtao Chen Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjingJiangsu 210016China Shenyang Aircraft Design&Research Institute ShenyangLiaoning 110000China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing 100076China China Aerodynamics Research and Development Center MianyangSichuan 621000China

Precise calculation of the trajectory of store separation is critical in assess-ing whether the store can be released *** ejection is the initial stage of the releasing process and any uncertainty introduced at this stage will propagate through the whole *** this work,the impact of the uncertainties in ejector modeling on the simulation of a generic store separation is investigated by using a Monte-Carlo-based *** reduce the extremely large computation cost resulted from the direct use CFD in Monte Carlo simulation,the CFD solutions are represented by a time-dependent Kriging model,which is constructed at each time step by using the samples from the URANS *** stochastic outputs,including the distri-bution of probability density function,expected value and 95%conﬁdence interval of store separation trajectory,are obtained by the Monte Carlo *** sensitiv-ity analysis is also carried out by using the Monte-Carlo-based method to determine the most signiﬁcant variables in ejector modeling,which affect the output *** results show that ejector modeling is one of the main uncertainty sources of store separation simulation and the approximation in ejector modeling can cause a signiﬁ-cant deviation,especially in the angular displacement.

关键词： Uncertainty quantification Monte Carlo simulation Kriging surrogate model store separation

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