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Control System Design for an unmanned helicopter to Track a Ground Target

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 420-427页

作者： XIN Zhekui FANG Yongchun Beijing Aerospace Automatic Control Institute Beijing 100854 China Institute of Robotics andInformation Automatic System Nankai University Tianjin 300071 China

Due to potential wide applications,the problem of utilizing an unmanned helicopter to track a ground target has become one of the most active research directions in related ***,in most cases,it is possible for a dynamic target to implement evasive actions with strong maneuverability,such as a sudden turn during high-speed movement,to flee from the tracker,which then brings much difficulty for the design of tracking control ***,most research on this field focuses on utilizing a ground mobile robot to track a high-speed ***,it is very difficult to extend those developed methods to airborne applications due to much more complex dynamices of UAV-target relative *** study investiages thoroughly for the problem of using an unmanned helicopter to track a ground target,with particular emphasis on the avoidance of tracking failure caused by the evasive maneuvers of dynamic ***,a novel control scheme,which consists of an innovative target tracking controller and a classical flight controller,is proposed for the helicopter-target tracking ***,the tracking controller,whose design is the focus of the paper,aims to utilize the motion information of the helicopter and the dynamic target to construct a suitable trajectory for the helicopter,so that when it flies along this trajectory,the relative pose between the helicopter and the dynamic target will be kept *** designing the target tracking controller,a novel coordinate transformation is firstly introduced to convert the tracking system into a more compact form convenient for control law design,the desired velocities for the helicopter is then proposed with consideration of the dynamic *** stability of the closed-loop system is finally analyzed by Lyapunov *** on Matlab/Simulink environment,two groups of simulation are conducted for the helicopter-target tracking control system where the target moves along a linear path

关键词： unmanned helicopter trajectory plan target tracking

Optimal flight parameters of unmanned helicopter for tea plantation frost protection

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International Journal of Agricultural and Biological Engineering 2015年第5期8卷 50-57页

作者： Hu Yongguang Liu Shengzhong Wu Wenye Wang Jizhang Shen Jianwen School of Agricultural Equipment Engineering Jiangsu UniversityZhenjiang 212013China Electronic Application Laboratory of Wuxi Hanhe unmanned helicopters Wuxi 214135China

To determine proper flight parameters of an unmanned helicopter for tea plantation frost protection,field experiments were conducted to study the impact of flight height,speed and interval on airflow disturbance and temperature rise around tea canopies based on the analysis and simulation of frost protection with a certain *** relationship between temperature rise after flight and the above flight parameters was established through a regression orthogonal experiment,based on which the optimal combination of flight parameters was obtained through the single-factor golden section *** results showed that wind speed around tea canopies decreased with the increase of flight height when flight speed was *** was a multivariate linear relationship between temperature rise and flight parameters,and the sequence of flight parameters’influence on frost protection effect was flight interval,flight height,flight *** optimal combination of flight parameters were flight height of 4.0 m,flight speed of 6.0 m/s and flight interval of 20 *** the flight with the above parameters air temperature around tea canopies increased 1.6℃ when background thermal inversion strength was 3.8℃.

关键词： thermal inversion frost protection unmanned helicopter flight parameters orthogonal experiment single-factor golden section method tea plants

Biologically adaptive robust mean shift algorithm with Cauchy predator-prey BBO and space variant resolution for unmanned helicopter formation

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Science China(Information Sciences) 2014年第11期57卷 195-207页

作者： WANG XiaoHua DUAN HaiBin State Key Laboratory of Virtual Reality Technology and Systems Beihang University

Visual tracking technology can provide measurement information for unmanned helicopter formation and thus, more attention is being paid to this research area. We propose a novel mean shift(MS) algorithm that is both adaptive and robust for unmanned helicopter formation and apply it to the leading unmanned helicopter tracking. The movement of an unmanned helicopter is very flexible and changeable, which makes the tracking there of more difficulty than for common targets. In creating an algorithm that can adapt to the acceleration of the unmanned helicopter and estimates both the scale and orientation of the movement changes, we combine the traditional MS with the bio-inspired Cauchy predator-prey biogeography-based optimization(CPPBBO)evolutionary algorithm, and also the space variant resolution(SVR) mechanism of the human visual system(MS-CPPBBO-SVR). To demonstrate the effectiveness and robustness of the proposed method and justify the importance of the CPPBBO algorithm and SVR mechanism at the same time, a series of comparative experiments were carried out. The experimental results of the proposed MS-CPPBBO-SVR method are compared with other competitive tracking methods, such as MS, MS with SVR(MS-SVR), MS-SVR with several other optimization algorithms, and the robust particle filter algorithm. The experimental results demonstrate that our proposed tracking approach, MS-CPPBBO-SVR, is more adaptive, robust and efficient in target tracking than the other methods.

关键词： unmanned helicopter formation tracking mean shift biogeography-based optimization(BBO) predator-prey space variant resolution(SVR)

Cable-driven legged landing gear for unmanned helicopter:Prototype design,optimization and performance assessment

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Science China(Technological Sciences) 2024年第4期67卷 1196-1214页

作者： TIAN BaoLin GAO HaiBo YU HaiTao SHAN HaoMin HOU JunChen YU HongYing DENG ZongQuan State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China China Academy of Aerospace Science and Innovation Beijing 100048China

unmanned helicopters equipped with adaptive landing gear will dramatically extend their application especially in dealing with challenging *** study presents a novel cable-driven legged landing gear(CLG)with differential transmission for unmanned helicopters in complex landing *** obtain the preferred configuration of the legged mechanism,a multi-objective optimization framework for the CLG is constructed by concurrently considering terrain adaptability,landing stability and reasonable linkage of internal *** non-dominated sorting genetic algorithmⅡis employed to numerically acquire the optimal scale parameters that guide the mechanical design of the *** unmanned helicopter prototype equipped with the devised CLG is developed with key performance *** results show that the devised CLG can provide energy-efficient support over uneven terrains(totally driven torque demand less than 0.1 N m)in quasi-static landing tests,and favorable terrain adaptability(posture fluctuation of the fuselage less than±1°)in unknown slope landing *** exhibited merits give the proposed CLG the potential to enhance the landing performance of future aircraft in extreme environments.

关键词： unmanned helicopter adaptive landing gear experimental verification

Modeling the yaw dynamics of an unmanned helicopter through modes partition method

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Science China(Technological Sciences) 2012年第1期55卷 182-192页

作者： WANG GuanLin XIA Hui YUAN XiaMing FAN Yong ZHU JiHong Department of Computer Science and Technology Tsinghua University Beijing 100084 China School of Automation Nanjing University of Science and Technology Nanjing 210094 China

The main difficulties in modeling yaw dynamics of a helicopter arise from the high nonlinearities,cross-couplings and dynam-ic uncertainties of these *** paper proposes a new identification approach for yaw dynamics modeling through modes partition method(MPM) with a concentrated search space limited by implicit human *** from first princi-ples and basic aerodynamics,the nonlinear equations of motion for yaw dynamics is *** model is linearized and transformed into a combination of dynamic modes,whose coefficients are identified from real-flight data through distributed genetic algorithm(DGA).The effectiveness of the approach is validated in terms of the identified model which can accurately capture the dynamic characters of the ***-and frequency-domain results clearly demonstrate the potential of MPM in modeling such complex systems.

关键词： dynamics identification unmanned helicopter genetic algorithm

Selection of a non-localized landing region for an unmanned helicopter based on an attention model

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Journal of Beijing Institute of Technology 2016年第3期25卷 392-396页

作者： NIE Zhen-gang School of Information and Electronics Beijing Institute of Technology Beijing 100081 China

A new landing region selection algorithm for an unmanned helicopter is proposed based on an attention *** from the original attention model,some properties of the possible safe landing regions（e.g.,depth,regional color and motion features）are included in the selection ***,regional color and motion features are fused directly into the saliency map because these features do not have the ＂central-peripheral＂*** results validate the feasibility and efficiency of this approach.

关键词： unmanned helicopter attention model automatic landing safe landing region

Design and test of centrifugal disc type sowing device for unmanned helicopter

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International Journal of Agricultural and Biological Engineering 2018年第2期11卷 55-61页

作者： Cancan Song Zhiyan Zhou Xiwen Luo Yubin Lan Xingang He Rui Ming Keliang Li Shahbaz Gul Hassan College of Engineering South China Agricultural University/Guangdong Engineering Research Center for Agricultural Aviation Application(ERCAAA)Guangzhou 510642China National Joint Research Center for Precision Agricultural Aviation Application Technology Guangzhou 510642China Key Laboratory of Key Technology on Agricultural Machine and Equipment(South China Agricultural University) Ministry of EducationGuangzhou 510642China

In China,it is difficult for manned aircraft to sow seeds in small and scattered plots,especially in areas including hills,swamps,telegraph poles,windbreaks,and residential areas;in such terrain,the sowing machinery cannot function ***,unmanned helicopters(UHs)are flexible enough to control and adapt to the complex environments that are not easily accessible by terrain sowing machinery and large agricultural aircraft,which have been widely used in *** this study,a centrifugal disc-type sowing device for an unmanned helicopter(CDTSDUH)was *** factors influencing the seed velocity when the seeds move away from the disc were explored by analyzing the forces of the seed acting on the sowing disc and the wind field of the *** influential factors include the distance from the falling mouth to the center of the disc,the offset angle of the falling mouth,and the rotation speed of the *** orthogonal test was designed with the sowing width and the curvature of the sowing area as the *** test results showed that the three factors mentioned above had a greater impact on the sowing width than the curvature of the seeding ***,the superior parameters of the disc were *** was also suggested that the above factor levels had little effect on the offset width of *** results of the test conducted for studying the sowing uniformity of the CDTSDUH indicated that the maximum and minimum difference values among the number of particles of the sampling points in the forward direction was 11 and 8,and the coefficient of variation of the number of particles in each row was more than 20%,indicating less uniformity was achieved when sowing in the lateral(perpendicular to the forward direction)direction,as compared to that in the forward *** study determined the ideal values for the radius of particles position,the offsetting angle,and the disc speed of the sowing machinery ***,considering that

关键词： sowing unmanned helicopter aircraft sowing centrifugal disc uniformity sowing disc

Height and Attitude Control for Small unmanned helicopter with Uncertainties and Disturbances 36

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Height and Attitude Control for Small Unmanned Helicopter wi...

Fuzzy Control of Small-scale unmanned helicopter

第36届中国控制会议

作者： Chao Ren Chaoyang Dong Qing Wang School of Aeronautic Science and Engineering Beihang University School of Automation Science and Electrical Engineering Beihang University

ISBN: (纸本)9781538629185

In this paper, a command filter-based backstepping controller is proposed for robust height and attitude tracking for small unmanned helicopter with flapping dynamics. Firstly, the helicopter model is divided into height subsystem and attitude subsystem, which are presented in strict feedback form. Then a second-order command filter is applied to obtain the derivative of virtual control laws and introduce amplitude and rate limits into control signals, thus the explosion of differentiation terms problem during backstepping process is solved, and actuators saturation is avoided. Meanwhile, the extended state observer（ESO） is designed to estimate and compensate the total uncertainty, which includes parametric uncertainties and external disturbances. Furthermore, globally bounded stability of the closed-loop helicopter system is proved by using Lyapunov ***, simulation results illustrate the applicability of the proposed controller in the presence of uncertain terms in the model.

关键词： unmanned helicopter Backstepping Command filter Extended state observer Flapping dynamics

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Fuzzy Control of Small-scale Unmanned helicopter