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Kinematics Analysis of Motion Simulation Subsystem for Unmanned Vehicle

Chinese Journal of Mechanical Engineering 2011年第6期24卷 923-934页

作者： TANG Guoming mei tao LIU Wei LI Bichun Institute of Intelligent Machines Chinese Academy of Sciences Hefei 230031 China Department of Precision Machinery ＆ Instrumentation University of Science and Technology of China Hefei 230026 China

Unmanned vehicle has attracted wide attention and interests throughout the world since it first deputed in the 1960s. However, the experimental methods for unmanned vehicle＇s intelligent behavior, such as semi-physical simulation and motion subsystem, have not been widely explored. First, the requirements of the motion subsystem in unmanned vehicle semi-physical facility are analyzed, and a six DOF parallel manipulator is selected to reproduce the pose of the vehicle. The link lengths of the motion subsystem are worked out under the given rotational angles of the vehicle. According to the geometric properties of tetrahedron, three joint positions of the top platform are determined, and the rest are obtained from the first three position vectors. Six constraint equations are set up based on the vertices on the top platform and the link lengths. In order to solve the six angle variables, a numerical algorithm built on the Newton-Raphson iterative method is presented, which is based on Taylor series expansion of six constraint equations. The pose of the top platform is ultimately calculated. The eigenvalues of the top platform are solved to obtain the natural frequencies of the motion subsystem. The coordinates of six joint centers on the top platform and six constraint equations can be realized by simple algebraic manipulation, which allows significant abbreviation in the formulation and provides a systematic way of obtaining the kinematic solution of the parallel manipulator. A numerical example is given and its efficacy is demonstrated by the inverse kinematics. The computation strategy based on tetrahedron method and Newton-Raphson iterative method provide a simple and cost-effective method for solving forward kinematics of six DOF parallel manipulators, and this method sheds light on other parallel manipulators.

关键词： unmanned vehicle motion simulation subsystem Tetrahedron method kinematics Newton-Raphson iterative method

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A Wheeled Wall-Climbing Robot with Bio-Inspired Spine Mechanisms

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Journal of Bionic Engineering 2015年第1期12卷 17-28页

作者： Yanwei Liu Shaoming Sun Xuan Wu tao mei Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Hefei 230026 China Institute of Advanced Manufacturing and Technology Hefei Institute of Physical Science Chinese Academy of Sciences Changzhou 213164 China

This paper presents a wheeled wall-climbing robot with the ability to climb concrete, brick walls using circular arrays of miniature spines located around the wheel. The robot consists of two driving wheels and a flexible tail, just like letter “T”, so it is called Tbot. The simple and effective structure of Tbot enables it to be steerable and to transition from horizontal to vertical surfaces rapidly and stably. Inspired by the structure and mechanics of the tarsal chain in the Serica orientalis Motschulsky, a compliant spine mechanism was developed. With the bio-inspired compliant spine mechanism, the climbing performance of Tbot was improved. It could climb on 100° （10° past vertical） brick walls at a speed of 10 cm·s^-1. A mechanical model is also presented to analyze the forces acting on spine during a climbing cycle as well as load share between multi-spines. The simu- lation and experiment results show that the mechanical model is suitable and useful in the optimum design of Tbot.

关键词： biologically-inspired robots climbing robots compliant spine mechanisms mechanical model wheeled robots

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Energy-efficient Bio-inspired Gait Planning and Control for Biped Robot Based on Human Locomotion Analysis

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Journal of Bionic Engineering 2016年第2期13卷 271-282页

作者： Hongbo Zhu Minzhou Luo tao mei Jianghai Zhao tao Li Fayong Guo Department of Automation School of Information Science and Technology University of Science and Technology of China Hefei 230022 China Institute of Advanced Manufacturing Technology Hefei Institutes of Physical Science Chinese Academy of Sciences Changzhou 213164 China

In this paper an experiment of human locomotion was carried out using a motion capture system to extract the human gait features. The modifiable key gait parameters affecting the dominant performance of biped robot walking were obtained from the extracted human gait features. Based on the modifiable key gait parameters and the Allowable Zero Moment Point （ZMP） Variation Region （AZR）, we proposed an effective Bio-inspired Gait Planning （BGP） and control scheme for biped robot to- wards a given travel distance D. First, we construct an on-line Bio-inspired Gait Synthesis algorithm （BGSN） to generate a complete walking gait motion using the modifiable key gait parameters. Second, a Bio-inspired Gait Parameters Optimization algorithm （BGPO） is established to minimize the energy consumption of all actuators and guarantee biped robot walking with certain walking stability margin. Third, the necessary controllers for biped robot were introduced in briefly. Simulation and experiment results demonstrated the effectiveness of the proposed method, and the gait control system was implemented on DRC-XT humanoid robot.

关键词： motion capture Allowable Zero Moment Point (ZMP) Variation Region (AZR) Bio-inspired Gait Planning (BGP) humanoid robot

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Effects of Process Parameters on the Temperature Field in Ti-6Al-4V Alloy Blade Precision Forging Process

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Journal of Materials Science & Technology 2006年第4期22卷 473-477页

作者： Yuli LIU He YANG tao GAO mei ZHAN College of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

Blade precision forging is a high temperature and large plastic deformation process. Process parameters have a great effect on temperature distribution in billet, so in this paper, by taking a Ti-6Al-4V alloy blade with a tenon as an object, the influence of process parameters on the temperature distribution in precision forging process was investigated using 3D coupled thermo-mechanical FEM （finite element method） code developed by the authors. The results obtained illustrate that：（1） the gradient of temperature distribution increases with increasing the deformation degree; （2） with increasing the initial temperature of the billet, the zones of high temperature become larger, and the gradient of temperature distribution hardly has any increase; （3） friction factors have little effect on the distribution of temperature field; （4） with increasing upper die velocity, temperature of the billet increases while the temperature gradient in billet decreases. The results are helpful to the design and optimization of the process parameters in precision forging process of Ti-alloy blade.

关键词： Ti-alloy blade Precision forging Process parameter Temperature field Finite element method (FEM)

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Counterion-Mediated Hydrogen Bonding Making Strong Polyelectrolytes pH-Responsive:Current Understanding and Perspectives

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Chinese Journal of Polymer Science 2024年第9期42卷 1270-1277,I0005页

作者： Yue Huang Guang-tao mei Zan Hua Guang-Ming Liu Hefei National Research Center for Physical Sciences at the Microscale Department of Chemical PhysicsKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei230026China The Key Laboratory of Functional Molecular Solids Ministry of Educationand Department of Materials ChemistrySchool of Chemistry and Materials ScienceAnhui Normal UniversityWuhu214002China

The counterion-mediated hydrogen bonding(CMHB)is related to the hydrogen bonding between bound counterions and polyelectrolyte chains in polyelectrolyte systems,where the counterions can both electrostatically bind to the charged groups of polyelectrolyte chains and act as hydrogen bond donors or acceptors to form hydrogen bonds with the hydrogen bond sites associated with polyelectrolyte chains simultaneously.A large number of literatures illustrate that strong polyelectrolytes(SPs)are insensitive to pH,which severely limmits the applications of SPs as smart ***,our studies have demonstrated that the CMHB makes SPs *** perspective discusses the mechanism of pH responsiveness of SPs and the pH-tunable properties of SPs,based on the pH-controlled CMHB *** future research directions on the pH responsiveness of SPs are also discussed *** is anticipated that the study of the pH responsiveness of SPs not only will provide a new understanding of the fundamental properties of SPs,but also will greatly expand the applications of SPs in the field of smart materials.

关键词： Counterion binding Hydrogen bond Polyelectrolyte brush Polyelectrolyte complexation

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Improved taylor-series location algorithm for cooperation networks

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 38-44页

作者： LIU Jun CUI Qi-mei tao Xiao-feng Key Laboratory of Ubiquitous Wireless Communication Beijing University of Posts and Telecommunications Beijing 100876 China

This article presents an iterative algorithm for estimating the location of the destination mobile station （DS） when some extra mobile stations around the DS are involved in and assist the base stations to complete the localization process. The proposed method is based on the taylor-series （TS） method and jointly estimates both the DS and the extra mobile stations, named reference mobile station （RS） in this article, positions simultaneously. Moreover, the time-differential-of-arrival （TDOA） measurements between DS and pairs of RSs are obtained by ultra-wide-band （UWB） signal, which is adept in accurate ranging application. According to the theoretic analysis, the Cramer-Rao lower bound （CRLB） of the modified TS algorithm reduces significantly. The actual performance, under a given simulation scenario, is enhanced by 25% at best.

关键词： UWB CRLB TS TDOA least-square (LS)

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A Bio-Inspired Biped Water Running Robot Incorporating the Watt-I Planar Linkage Mechanism

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Journal of Bionic Engineering 2013年第4期10卷 415-422页

作者： Linsen Xu tao mei Xianming Wei Kai Cao Mingzhou Luo Hefei Institutes of Physical Science Chinese Academy of Science Hefei 230031 P. R. China University of Science and Technology of China Hefei 230026 P. R. China Changzhou Institute of Advanced Manufacturing Technology Changzhou 213164 P. R. China

In this paper, a biped water running robot is developed by mimicking the water-running pattern of basilisk lizards. The dynamic mechanism of the robot was studied based on Watt-I planar linkages, and the movement trajectory of the double bar Assur Group was deduced to simulate the water-running foot trajectories of the basilisk lizard. A Central Pattern Generator （CPG）-based fuzzy control method was proposed to control the robot for realizing balance control and gait adjustment. The effectiveness of the proposed control method was verified on the prototype of a water running robot （weight： 320 g）. When the biped robot is running on water, the average force generated by the propulsion mechanism is 1.3 N, and the robot body tilt angle is 5~. The experiment results show that the propulsion mechanism is effective in realizing the basilisk lizards-like water running patterns, and the CPG-based fuzzy control method is effective in keeping the balance of the robot.

关键词： bio-inspired robot basilisk lizards-like robot biped water running CPG-based fuzzy control

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Modelling the Effects of Pest Control with Development of Pesticide Resistance

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 109-125页

作者： Bing LIU Bao-lin KANG Feng-mei tao Gang HU College of Mathematics and Information Science Anshan Normal UniversityAnshan 114007China

In this paper,we assume that the pest population is divided into susceptible pests and infected pests,and only susceptible pests do harm to *** the two methods of spraying pesticides and releasing infected pests and natural enemies to control susceptible pests(the former is applied more frequently),and assuming that only susceptible pests develop resistance to pesticides,a pest control model with resistance development is *** using the basic theory of impulsive differential systems and analytical methods,the sufficient condition for the global attractiveness of the susceptible pest eradication periodic solution is *** with numerical simulations,the effects of spraying frequency of pesticides on critical threshold conditions for eradicating susceptible pests are *** results confirm that it is not that the more frequently the pesticides are sprayed,the better the result of the pest control *** control strategies for eradicating susceptible pests are proposed:switching pesticides and releasing natural enemies ***,the parameters in the critical threshold are analyzed from the following two aspects:(1)The key factors affecting pest control are determined by parameter sensitivity *** results indicate that the correlation of the critical threshold concerning the killing efficiency rate and the decay rate of pesticides to susceptible pests varies due to the resistance development of susceptible pests.(2)Three-dimensional graphs and contours of susceptible pest eradication critical threshold with two parameters are simulated,and the effects of the main parameters on the critical threshold are analyzed.

关键词： pest control model resistance pesticide function susceptible pest eradication periodic solution

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A Track-type Inverted Climbing Robot with Bio-inspired Spiny Grippers

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Journal of Bionic Engineering 2020年第5期17卷 920-931页

作者： Yanwei Liu Limeng Wang Fuzhou Niu Pengyang Li Yan Li tao mei School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China School of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China Robotics Research Center Peng Cheng LaboratoryShenzhen 518055China

To enable the capacity of climbing robots to work on steep surfaces,especially on inverted surfaces,is a fundamental but challenging *** capacity can extend the reachable workspace and applications of climbing robots.A track-type inverted climbing robot called SpinyCrawler was developed in this *** a spiny track with an opposed gripping mechanism,the robot was experimentally demonstrated to have the ability of generating considerable adhesion to achieve stable inverted ***,to guarantee reliable attachment of the robot on rough ceilings,a spiny gripper inspired by the opposed gripping prolegs of caterpillars is designed,and a gripping model of the interaction between spines and the ceiling asperities is established and ***,a spiny track is developed by assembling dozens of spiny grippers to enable continuous attachment.A cam mechanism is introduced in the robot design without extra actuators to achieve stable attachment and easy detachment during continuous ***,climbing experiments are conducted on different surfaces,using a SpinyCrawler *** results demonstrated stable climbing ability on various rough inverted and vertical surfaces,including concrete walls,crushed stone walls,sandpaper walls,brick walls,and brick ceilings.

关键词： inverted climbing track-type robot rough ceiling bio-inspired spiny gripper

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Correlation of preoperative inflammatory factors and emotional disorders with postoperative delirium in patients with craniocerebral trauma

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World Journal of Psychiatry 2024年第7期14卷 1043-1052页

作者： Peng Cao Zhe-Yong Jia tao Zheng tao mei Department of Neurosurgery Changde HospitalXiangya School of MedicineCentral South University(The First People’s Hospital of Changde City)Changde 415003Hunan ProvinceChina

BACKGROUND Traumatic brain injury(TBI)imposes a substantial societal and familial burden due to its high disability and fatality rates,rendering it a serious public health *** patients with TBI have poor treatment outcomes and are prone to postoperative delirium(POD),which affects their quality of *** has been linked to increased POD incidence in some studies,while others have found no *** To investigate the correlation of POD risk factors,preoperative inflammatory factors,and mood disorders in patients with *** We retrospectively collected data on the treatment of 80 patients with TBI from November 2021 to September *** were grouped as POD and non-POD,according to their POD status,and the general data of the two groups were *** factor levels were detected preoperatively,and the Hamilton Depression Scale(HAMD)and Hamilton Anxiety Scale(HAMA)were used to investigate the risk factors associated with POD in these *** regression was used to identify the independent risk *** Twenty-one patients(26.25%)developed POD,including 7,10,and 4 cases of the excitatory,inhibitory,and mixed types,*** were 59 cases(73.75%)in the non-POD *** with the non-POD group,the POD group had a significantly higher proportion of patients with low Glasgow Coma Scale(GCS)scores before admission,unilateral mydriasis,preoperative hemorrhagic shock,intraventricular hemorrhage(IVH),and postoperative hyperglycemic hyperosmolar disease(P<0.05).In the POD group,interleukin-6(IL-6),human tumor necrosis factor-α(TNF-α),myeloperoxidase levels,HAMA,and HAMD scores were higher than those in the non-POD group(all P<0.05).Logistic multivariate analysis showed that GCS score at admission,IVH,IL-6,TNF-α,HAMA,and HAMD were independent risk factors for POD in patients with TBI(P<0.05).CONCLUSION Low GCS score at admission,IVH,elevated IL-6 and TNF-α,other inflammatory indicators,anxiety,and depress

关键词： Inflammatory factors Mood disorders Traumatic brain injury Postoperative delirium Relevance Risk factor

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