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第三十八届中国控制会议

作者： Liqian Dou Xiaotong Su Dandan Wang Yueping Wang School of Electrical and Information Engineering Aviation Key Laboratory of Science and Technology on Aircraft Control

This paper studied the problem of leader-following formation tracking control for multiple quadrotor unmanned aerial vehicles(UAV). The control object is to maintain the positions of follower quadrotors in formation with external disturbances and inner model parameter uncertainty. At the same time, only part of quadrotor UAV is informed to have access to the leader's position. Firstly, a second order robust exact differentiator(2-RED) observer is proposed. By using continues high-order sliding mode technique, the output feedback controller is designed to position outer-loop based on the result of the outer-loop ***, the output feedback controller and 2-RED observer are designed for attitude inner-loop. The finite-time stability of outer-loop and inner-loop controllers with observers are guaranteed through Lyapunov theories and homogeneity. Finally,numerical examples are presented to verify the developed algorithm.

关键词： Quadrotor UAV formation output feedback controller 2-RED observer

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Design and Simulation Analysis of Electric Drive Emergency Release System for Landing Gear Lock Mechanism

Design and Simulation Analysis of Electric Drive Emergency R...

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Asia-Pacific International Symposium on Aerospace technology, APISAT 2018

作者： Zhang, Jun Wei, Xiaohui Yin, Yin Key Laboratory of Fundamental Science for National Defense Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics NanjingJiangsu210016 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics NanjingJiangsu210016 China

ISBN: (纸本)9789811333040

In order to meet the needs of aircraft multi-electric development, an electric drive emergency release system was designed for the upper gear lock mechanism of a certain type of aircraft landing gear. Firstly, the mechanical equilibrium equation of the upper lock mechanism was established and theoretical analysis was carried out. Based on LMS Virtual. Lab/Motion and AMESim software, the dynamic models of the emergency lock release system of the landing gear and the electric drive system under different braking modes were established respectively, and the joint simulation was further realized. Finally, the effect of different braking modes on electric drive emergency release system was discussed in detail. The results show that the electric drive actuator of the short-circuit brake system, where the brushless DC motor drives the ball screw to unlock the upper lock and realizes the emergency unlock function, possesses the best driving effect. The analysis results provide theoretical support for the design of electric drive actuators of aircraft landing gear emergency system. © 2019, Springer Nature Singapore Pte Ltd.

关键词： Locks (fasteners)

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Hybrid deep neural network based prediction method for unsteady flows with moving boundaries

arXiv

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arXiv 2020年

作者： Han, Renkun Zhang, Zhong Wang, Yixing Liu, Ziyang Zhang, Yang Chen, Gang State Key Laboratory for Strength and Vibration of Mechanical Structures shannxi Key Laboratory for Environment and Control of Flight Vehicle School of Aerospace Engineering Xi’an Jiaotong University Xi’an710049 China Science and Technology on Reliability and Environment Engineering Laboratory Beijing Institute of Structure and Environment Engineering Beijing100076 China

A novel hybrid deep neural network architecture is designed to capture the spatial-temporal features of unsteady flows around moving boundaries directly from high-dimensional unsteady flow fields data. The hybrid deep neural network is constituted by the convolutional neural network (CNN), improved convolutional Long-Short Term Memory neural network (ConvLSTM) and deconvolutional neural network (DeCNN). Flow fields at future time step can be predicted through flow fields by previous time steps and boundary positions at those steps by the novel hybrid deep neural network. Unsteady wake flows around a forced oscillation cylinder with various amplitudes are calculated to establish the datasets as training samples for training the hybrid deep neural networks. The trained hybrid deep neural networks are then tested by predicting the unsteady flow fields around a forced oscillation cylinder with new amplitude. The effect of neural network structure parameters on prediction accuracy was analyzed. The hybrid deep neural network, constituted by the best parameter combination, is used to predict the flow fields in the future time. The predicted flow fields are in good agreement with those calculated directly by computational fluid dynamic solver, which means that this kind of deep neural network can capture accurate spatial-temporal information from the spatial-temporal series of unsteady flows around moving boundaries. The result shows the potential capability of this kind novel hybrid deep neural network in flow control for vibrating cylinder, where the fast calculation of high-dimensional nonlinear unsteady flow around moving boundaries is needed. Copyright © 2020, The Authors. All rights reserved.

关键词： Flow fields

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Fragile topologically protected perfect reflection for acoustic waves

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Physical Review Research 2020年第1期2卷 013131-013131页

作者： Chang-Yin Ji Yongyou Zhang Yunhong Liao Xiaoming Zhou Jian-Hua Jiang Bingsuo Zou Yugui Yao Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement (MOE) Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems and School of Physics Beijing Institute of Technology Beijing 100081 China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education and School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 People's Republic of China School of Physical Science and Technology and Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Suzhou China

Fragile topology is firstly demonstrated in acoustic crystals and then a realistic scheme is proposed to manipulate the transport of acoustic topological edge states (ATESs), i.e., by coupling them with side acoustic cavities. We find that single-mode cavities can completely flip the ATES pseudospin to form a perfect reflection, as long as their resonant frequencies fall into the topological band gap. The perfect reflection of the ATESs is protected by the fragile topology, which is proved by the one-dimensional topological waveguide-cavity transport theory. This fragile topologically protected perfect reflection is immune to the conventional defects (such as bending and disorder) and provides a realistic paradigm for manipulating the ATES transport. As examples, two potential applications, i.e., distance sensors and acoustic switches, are proposed based on the perfect reflection.

关键词： Acoustic wave phenomena Quantum transport Topological insulators

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Heading load dynamic simulation of landing gear test

Heading load dynamic simulation of landing gear test

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Asia-Pacific International Symposium on Aerospace technology, APISAT 2018

作者： Zhang, Zihao Wei, Xiaohui Ye, Qi Nanjing University of Aeronautics and Astronautics Nanjing China Key Laboratory of Fundamental Science for National Defense Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics NanjingJiangsu210016 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics NanjingJiangsu210016 China

ISBN: (纸本)9789811333040

In this paper, a force-measuring platform which is used to test the heading load of landing gear is analyzed, as well as the influences of its inertial forces on the accuracy of the test results. Two sets of drop test simulation models, considering or not considering the dynamometer platform, are built based on the dynamic simulation platform named LMS *** motion. The installation gap between the heading force sensor and the dynamometer platform is simulated through the form of spherical contact. The gap size was changed at two subsidence speeds of 1 m/s and 1.5 m/s, and the relationship between the gap size and the heading inertia force of the force-measuring platform was analyzed. According to the design requirements of the drop test in Book 14 of the Aircraft Design Manual, a drop test bench was built. The landing gear load of a high-speed UAV landing gear was measured and compared with the simulation results. © Springer Nature Singapore Pte Ltd 2019.

关键词： Dynamometers

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Recursive regret matching: A general method for solving time-invariant nonlinear zero-sum differential games

arXiv

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arXiv 2020年

作者： Liao, Wei Wei, Xiaohui Lai, Jizhou Key laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics NanjingJiangsu China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics NanjingJiangsu China College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing210001 China

In this paper, a new method is proposed to compute the rolling Nash equilibrium of the time-invariant nonlinear two-person zero-sum differential games. The idea is to discretize the time to transform a differential game into a sequential game with several steps, and by introducing state-value function, transform the sequential game into a recursion consisting of several normal-form games, finally, each normal-form game is solved with action abstraction and regret matching. To improve the real-time property of the proposed method, the state-value function can be kept in memory. This method can deal with the situations that the saddle point exists or does not exist, and the analysises of the existence of the saddle point can be avoided. If the saddle point does not exist, the mixed optimal control pair can be obtained. At the end of this paper, some examples are taken to illustrate the validity of the proposed *** Codes 91-08, 93-08 Copyright © 2020, The Authors. All rights reserved.

关键词： Game theory

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Optimization for conceptual design of reconfigurable UAV family

Optimization for conceptual design of reconfigurable UAV fam...

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Asia-Pacific International Symposium on Aerospace technology, APISAT 2018

作者： Zhou, Haoyu Ding, Ya Dai, Yalin Qian, Xiaoqiang Nanjing University of Aeronautics and Astronautics Yudao Street 29 Nanjing China Key Laboratory of Fundamental Science for National Defense Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics NanjingJiangsu210016 China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics NanjingJiangsu210016 China

ISBN: (纸本)9789811333040

The aircraft family is a set of aircraft products that share common components but vary in configurations based on different mission performance and requirements. The reconfigurable UAV family using modular design can improve the efficiency of executing multiple missions and enable the acquisition cost benefits, which is one of key competitive edges in military applications. This paper aims to study an effective optimization method for conceptual design of the reconfigurable UAV family with interchangeable components that can be reconfigured between missions. First, a Flying-wing UAV family defined for combat and reconnaissance missions is used as an example for demonstration of the method, and an appropriate comprehensive analysis model is developed. Next, the optimization formulation for the conceptual design of UAV family is presented in detail, including design variables, design constraints, and objectives. A hybrid optimization strategy is then applied to solve the optimization problem of UAV family conceptual design. The results after optimization indicate that the mission performance and requirements for each configuration are satisfied, and costs are reasonably compromised for the UAV family. © Springer Nature Singapore Pte Ltd 2019.

关键词： Conceptual design

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HRPGAN: A GAN-based Model to Generate High-resolution Remote Sensing Images 7

HRPGAN: A GAN-based Model to Generate High-resolution Remote...

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7th Annual International Conference on Geo-Spatial Knowledge and Intelligence, GSKI 2019

作者： Sun, Hai Wang, Ping Chang, Yifan Qi, Li Wang, Hailei Xiao, Dan Zhong, Cheng Wu, Xuelian Li, Wenbo Sun, Bingyu Co.Ltd Shanghai China Department of Airborne Remote Sensing National Disaster Reduction Center of China Beijing China Institute of Technology Innovation Hefei Institute of Physical Science Chinese Academy of Sciences Hefei China Third Research Institute of the Ministry of Public Security Shanghai China Guizhou Key Laboratory of Economics System Simulation Guizhou University of Finance and Economics Guiyang China Beijing Aerospace Flight Control Center Beijing China Institute of Intelligent Machines Chinese Academy of Sciences Hefei China

Generative adversarial networks (GAN) has been mainly used in the generation of natural images such as MNIST, CIFAR10 as well as Imagenet datasets and achieves satisfying generation results. However, GAN always fails in generating high quality high-resolution remote sensing images because remote sensing images are large in size and have various ground objects. To address this issue, a novel framework called High-Resolution PatchGAN (HRPGAN) is introduced in this paper. The structure of HRPGAN follows PatchGAN, but the batch normalization layers are removed and the ReLU activation is replaced by the SELU activation. In addition, a new loss function consisting of the adversarial loss, perceptual reconstruction loss and regularization loss is used in HRPGAN. Experiment results show that the proposed HRPGAN model generates the more diverse and lifelike images in HR remote sensing generation than Bicubic method and TGAN model. © Published under licence by IOP Publishing Ltd.

关键词： Chemical activation

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Classification of helicopter's typical flight state based on threshold

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IOP Conference Series: Materials science and Engineering 2021年第1期1207卷

作者： Li Sheng-nan Wang Jing-lin Yang Le ZhangShang-tian Aviation Industry Group Corporation Shanghai Institute of Aeronautical Measurement and Control Technology Shanghai 201601 China. Key Laboratory of Fault Diagnosis and Health Management Science and Technology. Shanghai 201601 China.

Dividing the 37 flying state of a certain line number helicopter. Firstly, dividing the helicopter rotation and single-engine flight. Secondly, performing preliminary state division for the remaining samlpes, the specific division of yaw angle, helicopter flight altitude and indicated air speed are different states, the least squares polynomial method is used for smoothing respectively. Calculating the extreme value of each parameter data, with the difference value of the extreme value of the parameter data being less than 10 as the limiting condition, dividing the original data segment into non-turning, level flight and steady speed state. The remaining sampling points are in the state of unsteady turning and non-level flight. Taking the difference value 0 as the limiting condition, further divide the non-steady speed and non-level flight state. Dividing the state of turning and non-turning, level flight, ascent and descent, steady speed, increase speed and deceleration state, which is the preliminary division state. Finally, dividing the near-ground and non-near-ground, classifying the helicopter status according to the height threshold, and analyze the accuracy of the classification results. The results show that this method is versatile, can quickly divide helicopters with different flight complexity, and has high accuracy.

关键词：

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A pilot study on an infrared jaw-tracking method for mandibular motion based on modified bite-fork registration: Accuracy and feasibility

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Journal of dentistry 2025年 159卷 105766页

作者： Bingran Du Xinyue Wang Hao Jiang Xiangxin Meng Yaopeng Pan Xiaohui Rausch-Fan Jianqiao Guo Xueyang Zhang Department of Stomatology The Eighth Affiliated Hospital of Southern Medical University (The First People's Hospital of Shunde Foshan) Foshan Guangdong 528308 China. MOE Key Laboratory of Dynamics and Control of Flight Vehicle School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China. School of Basic Medical Science Southern Medical University Guangzhou Guangdong 510515 China. Stomatological Hospital School of Stomatology Southern Medical University Guangzhou Guangdong 510280 China. Center of Clinic Research Division of conservative dentistry and periodontology University Dental Clinic Medical University Vienna Vienna 1090 Austria. MOE Key Laboratory of Dynamics and Control of Flight Vehicle School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China.. Electronic address: guojianqiao@***. Stomatological Hospital School of Stomatology Southern Medical University Guangzhou Guangdong 510280 China.. Electronic address: zhangxueyang666@***.

OBJECTIVES:Considering the risks and costs associated with repeated jaw-tracking due to positional changes in trackers, this study developed a novel method for repeated tracking without requiring secondary cone-beam computed tomography (CBCT) exposure or additional registration operations. METHODS:An infrared jaw-tracking method based on the registration of a modified bite-fork was developed. The accuracy of the method was evaluated by comparing head-simulator linear distance measurements obtained using the jaw-tracking and CBCT imaging methods and calculating the root mean square (RMS) errors associated with linear distance deviations. Feasibility was evaluated by analysing the opening-closing motion of the incisor in 15 participants, tracked by 15 dentists, and collecting ratings from both of them. RESULTS:Linear distance measurements showed no significant differences between the jaw-tracking and CBCT imaging methods at each position (all P > 0.05). The overall RMS errors of the jaw-tracking method were within 0.35 mm. Mean length of the opening curvilinear path (50.80 ± 6.86 mm) was not significantly different from the reported value (P = 0.684), and the intraclass correlation coefficient for the opening curvilinear path length was 0.947 (P < 0.001). A 'figure-eight' pattern of the opening-closing trajectory was observed. The mean rating score for each item was ≥4.0. CONCLUSIONS:This jaw-tracking method based on modified bite-fork registration enables repeated tracking without requiring secondary CBCT radiation exposure or additional registration operations. CLINICAL SIGNIFICANCE:The infrared jaw-tracking method offers a promising approach for short-term repeated evaluation of mandibular motion due to its low radiation exposure and minimal chair-site costs.

关键词： Bite-fork registration Infrared tracking Mandibular motion

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