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| 1 | CALIBRATION OF A 6-DOF SPACE ROBOT USING GENETIC ALGORITHM显示文摘The kinematic error model of a 6-DOF space robot is deduced,and the cost function of kinematic parameter identification is built.With the aid of the genetic algorithm (GA) that has the powerful global adaptive probabilistic search ability,24 parameters of the robot are identified through simulation,which makes the pose (position and orientation) accuracy of the robot a great improvement.In the process of the calibration,stochastic measurement noises are considered.Lastly, generalization of the identified kinematic parameters in the whole workspace of the robot is discussed. The simulation results show that calibrating the robot with GA is very stable and not sensitive to measurement noise.Moreover,even if the robot's kinematic parameters are relative,GA still has strong search ability to find the optimum solution. | LIU Yu JIANG Yanshu LIANG Bin XU Wenfu | 2008 | Chinese Journal of Mechanical Engineering2008，21，6： | 15 |
| 2 | Population Genomic Analysis and De Novo Assembly Reveal the Origin of Weedy Rice as an Evolutionary Game显示文摘Crop weediness,especially that of weedy rice(Oryza sativa f.spontanea),remains mysterious.Weedy rice possesses robust ecological adaptability;however,how this strain originated and gradually formed proprietary genetic features remains unclear?Here,we demonstrate that weedy rice at Asian high latitudes(WRAH)is phylogenetically well defined and possesses unselected genomic characteristics in many divergence regions between weedy and cultivated rice.We also identified novel quantitative trait loci underlying weedy-specific traits,and revealed that a genome block on the end of chromosome 1 is associated with rice weediness.To identify the genomic modifications underlying weedy rice evolution,we generated the first de novo assembly of a high-quality weedy rice genome(WR04-6),and conducted a comparative genomics study between WR04-6 with other rice reference genomes.Multiple lines of evidence,including the results of demographic scenario comparisons,suggest that differentiation between weedy rice and cultivated rice was initiated by genetic improvement of cultivated rice and that the essence of weediness arose through semi-domestication.A plant height model further implied that the origin of WRAH can be modeled as an evolutionary game and indicated that strategy-based selection driven by fitness shaped its genomic diversity. | Jian Sun Dianrong Ma Liang Tang Minghui Zhao Guangchen Zhangh Wenjia Wang Jiayu Song Xiang Li Zimeng Liu Wenxing Zhang Quan Xu Yuncheng Zhou Jianzhong Wu Toshio Yamamoto Fei Dai Yan Lei Song Li Gang Zhou Hongkun Zheng Zhengjin Xu Wenfu Chen | 2019 | Molecular Plant2019，12，5： | 9 |
| 3 | Area-oriented coordinated trajectory planning of dual-arm space robot for capturing a tumbling target显示文摘The growing amount of space debris poses a threat to operational spacecraft and the long-term sustainability of activities in outer space. According to the orbital mechanics, an uncontrolled space object will be tumbling, bringing great challenge to capture and remove it. In this paper, a dual-arm coordinated ‘‘Area-Oriented Capture'(AOC) method is proposed to capture a non-cooperative tumbling target. Firstly, the motion equation of the tumbling target is established, based on which, the dynamic properties are analyzed. Then, the ‘‘Area-Oriented Capture'concept is presented to deal with the problem of large pose(position and attitude) deviation and tumbling motion. An area rather than fixed points/devices is taken as the object to be tracked and captured. As long as the manipulators’ end-effectors move to a specified range of the objective areas(not fixed points on the target, but areas), the target satellite will be hugged by the two arms.At last, the proposed method and the traditional method(i.e. fixed-point oriented capture method)are compared and analyzed through simulation. The results show that the proposed method has larger pose tolerance and takes shorter time for capturing a tumbling target. | Wenfu XU Lei YAN Zhonghua HU Bin LIANG | 2019 | Chinese Journal of Aeronautics2019，32，9： | 8 |
| 4 | Characteristics of pantograph‐catenary arc under low air pressure and strong airflow显示文摘Pantograph‐catenary arc fault is the primary factor threatening the stability of the power transmission for high‐speed railway.The motion characteristics of the pantograph‐catenary arc under low air pressure and strong airflow is significantly different from the case under atmospheric pressure.In this paper,an experimental platform of panto-graph‐catenary arc was built to investigate arc root position‐time and arc column lon-gitudinal drift height‐time characteristic curves under different air pressures and airflow velocites.Via analysing the corresponding results,it can be found that there are different arc root-arc column traction mechanisms at different stages of arc development.The arcing time and arc root stagnation time under low air pressure are significantly longer than the case under atmospheric pressure,resulting in more serious electrode ablation.The arc column longitudinal drift velocity and height are greater with the increase of airflow velocity.Two typical irregular arc motion phenomena-arc root jumping and arc reignition are observed.To clarify the internal mechanism of the above phenomenon,a magnetohydrodynamics(MHD)model of the pantograph‐catenary arc was lauched,the influence mechanism of the pantograph‐catenary arc temperature and voltage are studied,and the physical process of arc temperature oscillation is analysed.The research results provide theoretical support for arc protection in high‐altitude areas. | Zhilei Xu Guoqiang Gao Wenfu Wei Zefeng Yang Wenhan Xie Keliang Dong Yaguang Ma Yan Yang Guangning Wu | 2022 | High Voltage2022，7，2： | 7 |
| 5 | Vibration suppression of a large flexible spacecraft for on-orbit operation显示文摘Flexible appendages, such as solar panels, communication antennas and other large structures, are mounted on the base of a space robot and target satellite. The vibration of the flexible structure is excited by operations of a space manipulator. It is very challenging to control the vibration of large flexible appendages for on-orbit operation and, especially when the manipulator operates a non-cooperative target with unknown structural parameters and vibration information. In this study, a hybrid control method is proposed based on wave-based control and PD control methods to control the motion of a manipulator while suppressing the vibration of appendages. First, the rigid-flexible coupled dynamic model of a compounded system is established.This is followed by designing a hybrid control strategy combining wave-based control and PD control for restto-rest maneuvers based on the characteristics of the compounded system. Finally, the simulation of a 3D compounded system is provided to verify the effectiveness of the presented approach. The simulation results indicate that the space robot can successfully berth the target while suppressing the vibrations of the structure. | Deshan MENG Houde LIU Yanan LI Wenfu XU Bin LIANG | 2017 | Science China(Information Sciences)2017，60，5： | 6 |
| 6 | Design principles and parameters of rice ideal panicle type显示文摘On the basis of many years of research at the laboratory, and by making reference to the related literature published at home and abroad, in this paper the concept of rice ideal panicle type was introduced, and the principles of rice ideal panicle type design were elucidated. The parame-ters of rice ideal panicle type for Liaoning were preliminarily established as follows: Panicle length <17 cm, neck-panicle curvature <40°, neck panicle length 3―4 cm, neck diameter >2 mm, large vascular bundle and primary branch >15 pieces/panicle, primary branch grain >80 grains/panicle, secondary branch grains concentrating in the middle and upper parts of panicle axis, and panicle type index >0.5. In addition, the possibility of achieving unity of grain yield and quality at a still higher level by creating an ideal panicle type was explored. | XU Zhengjin CHEN Wenfu ZHANG Longbu YANG Shouren | 2005 | Chinese Science Bulletin2005，50，19： | 6 |
| 7 | Pantograph-catenary electrical contact system of high-speed railways:recent progress,challenges,and outlooks显示文摘As the unique power entrance,the pantograph-catenary electrical contact system maintains the efficiency and reliability of power transmission for the high-speed train.Along with the fast development of high-speed railways all over the world,some commercialized lines are built for covering the remote places under harsh environment,especially in China;these environmental elements including wind,sand,rain,thunder,ice and snow need to be considered during the design of the pantograph-catenary system.The pantograph-catenary system includes the pantograph,the contact wire and the interface—pantograph slide.As the key component,this pantograph slide plays a critical role in reliable power transmission under dynamic condition.The fundamental material characteristics of the pantograph slide and contact wire such as electrical conductivity,impact resistance,wear resistance,etc.,directly determine the sliding electrical contact performance of the pantograph-catenary system;meanwhile,different detection methods of the pantograph-catenary system are crucial for the reliability of service and maintenance.In addition,the challenges brought from extreme operational conditions are discussed,taking the Sichuan-Tibet Railway currently under construction as a special example with the high-altitude climate.The outlook for developing the ultra-high-speed train equipped with the novel pantograph-catenary system which can address the harsher operational environment is also involved.This paper has provided a comprehensive review of the high-speed railway pantograph-catenary systems,including its progress,challenges,outlooks in the history and future. | Guangning Wu Keliang Dong Zhilei Xu Song Xiao Wenfu Wei Huan Chen Jie Li Zhanglin Huang Jingwei Li Guoqiang Gao Guozheng Kang Chuanjun Tu Xingyi Huang | 2022 | Railway Engineering Science2022，30，4： | 5 |
| 8 | A Light Space Manipulator with High Load-to-Weight Ratio: System Development and Compliance Control显示文摘In order to meet the requirements of the space environment for the lightweight and load capacity of the manipulator,this paper designs a lightweight space manipulator with a weight of 9.23 kg and a load of 2 kg.It adopts the EtherCAT communication protocol and has the characteristics of high load-to-weight ratio.In order to achieve constant force tracking under the condition of unknown environmental parameters,an integral adaptive admittance control method is proposed.The control law is expressed as a third-order linear system equation,the operating environment is equivalent to a spring model,and the control error transfer function is derived.The control performance under the step response is further analyzed.The simulation results show that the proposed integral adaptive admittance control method has better performance than the traditional method.It has no steady-state error,overcomes the problems caused by nonlinear discrete compensation,and can facilitate analysis in the frequency domain,realize parameter optimization,and improve calculation accuracy. | Zhiwei Wu Yongting Chen Wenfu Xu | 2021 | Space(Science & Technology)2021，，1： | 3 |
| 9 | Effect of Rice Breeding Process on Improvement of Yield and Quality in China显示文摘Rice,Oryza sativa,is a major global food staple,90%of which is cultivated in Asian countries.Its two major subspecies are japonica and indica,differing in geographical distribution and morphological characteristics(Wang W S et al,2018).The indica subspecies occupies 90%of the rice cultivation area,as opposed to only 10%occupied by the japonica subspecies,which is mainly distributed in northern China,Japan and Korea(Xu and Chen,2016).China is the only country in which japonica and indica are of equal importance.Two-thirds of the rice grown in China is indica,which is cultivated mostly in low-altitude and low-latitude regions,and one-third is japonica,farmed prevalently in high-altitude and high-latitude regions(Wang Y H et al,2018).After the introduction of semi-dwarf gene sdl,the ideal plant architecture breeding and the application of the Fi hybrid,accompanied by the improvement of cultivation methods and field management。 | Fei Cheng Xu Quan Xu Zhengjin Chen Wenfu | 2020 | Rice science2020，27，5： | 3 |
| 10 | HIT-Hawk and HIT-Phoenix: Two kinds of flapping-wing flying robotic birds with wingspans beyond 2 meters显示文摘Inspired by large and medium-sized birds,two kinds of flapping-wing flying robots with wingspans beyond 2 meters were developed.They have the appearance of a hawk and a phoenix respectively,so they are called HIT-Hawk and HIT-Phoenix.In this paper,the bionic concept,theoretical analysis,design and manufacturing are introduced in detail.Firstly,the flight principle and characteristics of large and medium-sized birds were summarized.Then,the aerodynamics was modeled based on the thin airfoil theory,and the main design basis was established.Secondly,the mechanical structures of HIT-Hawk and HIT-Phoenix were designed to ensure the lateral and longitudinal stability and have optimized flight performance.Moreover,an autonomous flight control method was proposed and realized in highly integrated on-onboard controller;it satisfies the strict restrictions on mass,size,power and shape.Finally,the prototypes were fabricated and verified through practical flight experiments.The wingspans of these two flapping wing aircrafts are 2.0 m and 2.3 m respectively,the take-off weights are 1.15 kg and 0.86 kg,and the maximum stable endurance is 65 min(with battery of 3S LiPo,4300 mAh)and 8 min(with battery of 3S LiPo,800 mAh).Their wind resistance can both reach level 4.Compared with the small and micro flapping-wing aerial vehicles that mimic insects or small birds,they both have strong load capacity,strong wind resistance and long endurance. | Erzhen Pan Hui Xu Han Yuan Jianqing Peng Wenfu Xu | 2021 | Biomimetic Intelligence & Robotics2021，1，1： | 2 |
| 11 | Autonomous target capturing of free-floating space robot:theory and experiments显示文摘 | Xu Wenfu Liang Bin Li Cheng | | 0，，03： | 1 |
| 12 | The structure-directing effect of n-propylamine in the crystallization of open-framework aluminophosphates显示文摘Using n-propylamine as a template,deioned water and secondary-butanol(butan-2-ol)as solvents,a three-dimensional(3D)open-framework aluminophosphate[C3NH10]·[HAl3P3O13](1)and a two-dimensional layered aluminophosphate[C3NH10]3·[Al3P4O16](2)were crystallized from the initial mixtures with compositions of Al2O3:2.4 P2O5:5.0 n-propylamine:100 H2O/butan-2-ol,respectively.They are characterized by X-ray powder diffraction(XRD),thermogravimetric(TG),and elemental(CHN)analyses and structurally determined by single-crystal X-ray diffraction analysis.Compound 1 crystallizes in the monoclinic space group P21/c with a=0.85831(13)nm,b=1.7677(3)nm,c=1.04353(12)nm,=123.887(9)°,and V=1.3143(3)nm3.Compound 2 crystallizes in the monoclinic space group P21/c with a=1.1313(2)nm,b=1.4874(3)nm,c=1.8020(6)nm,=125.07(2)°,and V=2.4817(11)nm3.The results show that the properties of solvent have a significant influence on the structure-directing effect of n-propylamine in the crystallization of the open-framework aluminophosphates. | LU HuiYing YAN Yan TONG XiaoQiang YAN WenFu YU JiHong XU RuRen | 2014 | Science China Chemistry2014，57，1： | 1 |
| 13 | Study on the stability of Tethered Satellite System显示文摘 | Yong He Bin Liang Wenfu Xu | 2011 | Acta Astronautica2011，，11： | 1 |
| 14 | Unified Multi-domain Modeling and Simulation of Space Robot for Capturing a Moving Target 显示文摘 | Wenfu Xu Yu Liu Bin Liang Xueqian Wang Yangsheng Xu | 2010 | Multibody System Dynamics2010，23，3： | 1 |
| 15 | An anionic aluminophosphate molecular sieve with Brnsted acidity显示文摘 | YAN Wenfu YU Jihong XU Ruren | 2000 | Chem Mater2000，12，： | 1 |
| 16 | Study on non-holonomic Cartesian path planning of free-floating space robotic system显示文摘 | XU Wenfu LIU Yu XU Yangsheng | 2009 | Advanced Robotics2009，23，1： | 1 |
| 17 | A ground experiment system of free-floating robot for capturing space target显示文摘 | Xu Wenfu Liang Bin Xu Yangsheng | 2007 | Jour- nal of Intelligent and Robotic Systems2007，48，2： | 1 |
| 18 | Survey of modeling, planning, and ground verification of space robotic systems 显示文摘 | XU Wenfu LIANG Bin XU Yangsheng | 2011 | Acta Astronautica2011，68，： | 1 |
| 19 | Study on the Stability of Tethered Satellite System 显示文摘 | He Yong Liang Bin Xu Wenfu | 2011 | ActaAstronautica2011，，68： | 1 |
| 20 | Structure-directing Effect on Synthesis of Layered Aluminophosphates with Same Topology显示文摘 | WANG Aitian XU Jun WANG Chao DENG Feng XU Ruren YAN Wenfu | 2017 | Chemical Research in Chinese Universities2017，33，4： | 1 |
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