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Parameter-Free Shifted Laplacian Reconstruction for Multiple Kernel Clustering

IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： Xi Wu Zhenwen Ren F.Richard Yu the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010China the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian.

关键词： parameter letter Parameter

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Improving aircraft nose wheel steering stability based on control continuation method

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science China(Technological sciences) 2025年第3期68卷 258-277页

作者： Qiaozhi YIN Dexu KONG Jiawei WANG Hong NIE Xiaohui WEI National Key Laboratory of Helicopter Aeromechanics Nanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing210016China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing211106China

aircraft steering instability during the taxiing process sometimes occurs resulting from the unstable bifurcation phenomena of the nonlinear steering dynamic system,which may lead to severe *** this study,the control parameter design of an aircraft nose wheel steering control system based on the control continuation method is proposed to reduce the number of unstable bifurcation points and enlarge the system stable region area in a certain parameter ***,the aircraft turning performance can be improved ***,a nonlinear aircraft rollout dynamic model is constructed,and the aircraft ground steering bifurcation characteristics are obtained under the open-loop steering control ***,the bifurcation performances under three closed-loop nose wheel steering controllers based on the feedback control method are compared,and the control parameter of the quadratic nonlinear controller with a better bifurcation control effect is selected as a second bifurcation parameter to analyze the directional system stability via two-parameter bifurcation ***,the influence of a crosswind on the aircraft ground steering bifurcation performance is studied for various control parameter ***,the control effects of a traditional proportional-integral-derivative(PID)nose wheel steering control law and the designed feedback controller are compared and ***,a semi-physical experiment of the aircraft nose wheel steering system is carried out,and different control parameter values are selected for test verification,which can further verify the control effect of the designed nonlinear feedback *** results indicate that the feedback control method is unable to vary the system bifurcation types,but appropriate control parameter design can effectively shrink the system instability region and even eliminate the unstable Hopf bifurcation points under some specific working conditions,improving the aircraft ground turning stability re

关键词： aircraft taxiing dynamics and stability nose wheel steering control system control continuation steering bifurcation characteristics quadratic feedback control

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Structural non-reciprocity study of optical systems for RFOGs driven by broad-spectrum light sources

Structural non-reciprocity study of optical systems for RFOG...

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2024 International Conference on Optoelectronic Information and Optical Engineering, OIOE 2024

作者： Su, Zhengcheng Yan, Bo Li, Jun Lan, Shiqi National Key Laboratory of Science and Technology on Aircraft Control Flight Automatic Control Research Institute Shaanxi Xi’an710076 China

ISBN: (数字)9781510680470

ISBN: (纸本)9781510680463

Aiming at the structural asymmetry problem caused by the inconsistency of the two optical fibers connecting the Y waveguide and the resonant cavity in the RFOG optical system driven by a broad-spectrum light source, a study on the non-reciprocity of the optical structure of the RFOG driven by a broad-spectrum light source was carried out. A model of the optical system structure non-reciprocity is established, and the effect of the optical system structure non-reciprocity on the gyroscope system in a variable temperature environment is analyzed. The results show that the optical system structure non-reciprocity causes the gyro sweep mode curve to change, but does not affect the system accuracy when there is no temperature change, and the temperature characteristics of the optical system structure non-reciprocity lead to pseudo-rotational speed output of the gyro output in a variable temperature environment, which is strongly correlated with the length difference and the rate of change of temperature. © 2024 SPIE.

关键词： Light sources

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Research on Cooperative Path Planning and Formation control for Multiple UAVs 1

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7th Chinese Conference on Swarm Intelligence and Cooperative control, CCSICC 2023

作者： Shichao, Ma Xianglun, Zhang Qiang, Tang Zhiyu, Li Yukun, Yang AVIC Xi’an Flight Automatic Control Research Institute Xi’an710076 China National Key Laboratory of Science and Technology on Aircraft Control Xi’an710076 China

ISBN: (数字)9789819733361

ISBN: (纸本)9789819733354

Considering the background of Multi-UAVs formation cooperation, a Cooperative Multi-Swarm Particle Swarm Optimization (CMS-PSO) scheme as well as a prescribed performance control (PPC) method is introduced. Firstly, the cost function is developed and a novel CMS-PSO approach is applied to deal with three dimensional (3D) path planning problem. Then, the nonlinear mathematical formation model is given. So as to confine the location differences of the formation system, a PPC algorithm integrated with the backstepping methodology is constructed in details. In the end, the results of mathematical simulations show the validity of the introduced path algorithm and control method. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Cost functions

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Refined modeling and experimental verification of a torque motor for an electro-hydraulic servo valve

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Chinese Journal of Aeronautics 2023年第6期36卷 302-317页

作者： Zhichuang CHEN Shenghong GE Yulei JIANG Wenhao CHENG Yuchuan ZHU National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing Engineering Institute of Aircraft SystemsNanjing 210061China AVIC Nanjing Servo Control System Co. LtdNanjing 210032China

The Permanent Magnet Torque Motor(PMTM)is the key electro-mechanical conversion device in an Electro-Hydraulic Servo Valve(EHSV).In this work,a refined model of a PMTM is developed,considering the non-working air-gaps between the upper or lower yoke and the armature,the fringing effect at the limiting holes,and the nonlinear permeability of soft magnetic *** on the refined model,the influences of various factors on the calculation accuracy of the magnetic flux at the pole surfaces of the armature and the output torque are *** verifying the validity of the refined model,a Finite Element Analysis(FEA)of the PMTM is conducted,and a test platform is *** with existing models,the refined model can better reveal the intrinsic mechanism of the PMTM,and its calculations are more consistent with the FEA *** experimental results of the armature deflection displacement show that the refined model can accurately describe the output characteristics of the PMTM.

关键词： Calculation accuracy Electro-hydraulic servo valve Experimental verification Finite element analysis Refined model Torque motor

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Research on longitudinal control technology in the transition section of tilt-rotor aircraft based on linear active disturbance rejection control 2

Research on longitudinal control technology in the transitio...

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2023 2nd International Conference on Aerospace and control Engineering, ICoACE 2023

作者： Xu, Shaofeng Chang, Shaoping Shi, Pengfei Wang, Lin AVIC Xi'An Flight Automatic Control Research Institute Xi'an710065 China National Key Laboratory of Science and Technology on Aircraft Control Xi'an710065 China

To solve the problem of strong coupling and control redundancy in the transition section of the tilt-rotor, this paper presents a longitudinal control method based on linear active disturbance rejection control (LADRC), verified by simulation. Firstly, the nonlinear dynamics model of tilt-rotor aircraft based on the mechanism method is established, and the model's accuracy is verified by comparing the trim result with the generic tilt-rotor aircraft simulation (GTRS) model verified by flight test in XV-15. Then, the control and redundant rudder surface assignment strategies for tilt-rotor aircraft are proposed. Then, the vertical and vertical control law of tilt-rotor aircraft is designed, the linear expansion state observer (LESO) model is analyzed and derived, and the linear active disturbance rejection controller suitable for attitude loop control of tilt-rotor is designed. The altitude and velocity loops are controlled. Finally, the proposed linear active disturbance rejection control (LADRC) controller is verified by simulation, and the whole process of tilting transition is simulated. The results show that the proposed control strategy and the controller designed in this paper have strong anti-disturbance ability, fast response speed, and high control precision and can be used in the transition section of tilt-rotor aircraft. The vertical direction shall be well controlled. © Published under licence by IOP Publishing Ltd.

关键词： controllers

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An Optimization Method for the Swing of a Quadrotor Flight Suspension System 25

An Optimization Method for the Swing of a Quadrotor Flight S...

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25th IEEE China Conference on System Simulation technology and its Application, CCSSTA 2024

作者： Yang, Sen Zang, Xinlian Tong, Jigang Xie, Tian Jin, Xin Tianjin University of Technology The School of Electrical Engineering and Automation Tianjin China AVIC Xi'an Flight Automatic Control Research Institute National key laboratory of science and technology on aircraft control Xi'an China

ISBN: (纸本)9798350366600

The aim of this study is to explore optimization control methods for suspension systems during the flight of quadcopters. The traditional control method of suspension system has some problems such as oscillation and instability, so an optimization scheme based on Gaussian pseudo-general algorithm is proposed in this paper. Through numerical simulation and actual flight test, the effectiveness of the optimization algorithm in improving system stability and reducing oscillation amplitude is verified. At the same time, this study conducted a comparative analysis of the suspension system of the quadrotor vehicle and the free fall body, and the optimization algorithm is found to be feasible and can well improve the control accuracy and stability of the system, and provide strong support for the safety of the quadrotor vehicle in various application scenarios. © 2024 IEEE.

关键词： Flight testing

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A Enhanced Feature Extraction for 3D Object Detection 25

A Enhanced Feature Extraction for 3D Object Detection

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25th IEEE China Conference on System Simulation technology and its Application, CCSSTA 2024

作者： Meng, Qingao Tong, Jigang Yang, Sen Xie, Tian Jin, Xin Tianjin University of Technology The School of Electrical Engineering and Automation Tianjin China Avic Xi'an Flight Automatic Control Research Institute National Key Laboratory of Science and Technology on Aircraft Control Xi'an China

ISBN: (纸本)9798350366600

3D object detection is crucial for autopilot and augmented reality applications. However, accurate feature extraction is the key to achieve high-precision detection, but traditional methods face the challenges of information loss and computational inefficiency. To address this, we propose an enhanced feature extraction method. We first divide the 3D space into voxel grids of varying scales. Then, using 3D sparse convolution, we extract features which are compressed along the Z axis to form BEV (Bird's Eye View) feature images. An efficient multi-scale attention mechanism is then employed to enhance these BEV features. The refined feature map is subsequently located and classified through a CT-stacking module and RPN (Region Proposal Network). Voxel features from the proposal and 3D backbone are passed through a voxel RoI pool to directly extract RoI features from the 3D features for further refinement. Finally, a cascaded attention network refines the proposal and strengthens confidence prediction. Experiments on test set validate our method effectiveness, showing improved accuracy over traditional voxel methods. Overall, this enhanced feature extraction technique offers a promising solution for 3D target detection, particularly in scenarios demanding high real-time performance and precision. © 2024 IEEE.

关键词： Feature extraction

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Design and Implementation of a Ground control Station for Multiple Fixed-Wing UAVs

Design and Implementation of a Ground Control Station for Mu...

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International Conference on Guidance, Navigation and control, ICGNC 2022

作者： Wen, Jiayun Tang, Qiang Li, Hao AVIC Xi’an Flight Automatic Control Research Institute Xi’an710076 China National Key Laboratory of Science and Technology on Aircraft Control Laboratory Xi’an710076 China

ISBN: (纸本)9789811966125

In recent years, Unmanned Aerial Vehicles (UAVs) have been used in many fields by virtue of their flexible design, low cost and zero casualties. With the deepening application of UAVs, the tasks they undertake are gradually becoming more complex and can no longer be accomplished by a single UAV alone, so multiple UAVs are needed to collaborate in order to perform the tasks. In this paper, a UAV ground control station software system is designed for the characteristics of multiple UAVs to perform tasks. The system is designed with the key requirement of reducing the operator’s workload in mind, while taking into account the differences in control and surveillance between multiple UAVs and a single UAV. After defining the functional requirements of the ground control station, the development and implementation of the ground station software is carried out, and finally, an application example of the ground station software is presented. The experiments show that the proposed ground station has some engineering value. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Fixed wings

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Formation control of UAVs with Prescribed Performance Based on Backstepping Method

Formation Control of UAVs with Prescribed Performance Based ...

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International Conference on Guidance, Navigation and control, ICGNC 2022

作者： Ma, Shichao Zhang, Xianglun Yang, Yukun Zang, Xiheng AVIC Xi’an Flight Automatic Control Research Institute Xi’an710076 China National Key Laboratory of Science and Technology on Aircraft Control Xi’an710076 China

ISBN: (纸本)9789811966125

In order to deal with the formation control problem for multiple unmanned aerial vehicles (UAVs), a prescribed performance control (PPC) scheme based on backstepping method is developed. Firstly, the nonlinear mathematical model with bounded external disturbance is established. Meanwhile, the tracking error model of UAV formation is formulated on the basis of graph theory. For the purpose of limiting the tracking error within a small range, a performance function is recommended. Furthermore, considering that the direct processing of the initial system has great difficulties, an error transformation function is adopted. Based on PPC theory, the structure of the control law is deduced by utilizing the backstepping method. In addition, the derivation process of stability analysis is shown in detail. The simulation results show the superiority of trajectory tracking performance, which demonstrates the validity of the designed control scheme. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Graph theory

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