检索结果-南通市图书馆

A-STC: auction-based spanning tree co.erage algorithm for motion planning of co.perative robots

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information technology & Electronic Engineering 2019年第1期20卷 18-31页

作者： Guan-qiang GAO Bin XIN School of Automation Beijing Institute of Technology Key Laboratory of intelligent control and Decision of co.plex Systems beijing Advanced Innovation Center for intelligent Robots and Systems

The multi-robot co.erage motion planning(MCMP) problem in which every reachable area must be co.ered is co.mon in multi-robot systems. To deal with the MCMP problem, we propose an efficient, co.plete, and off-line algorithm, named the "auction-based spanning tree co.erage(A-STC)" algorithm. First, the co.figuration space is divided into mega cells whose size is twice the minimum co.erage range of a robot. Based on co.nection relationships among mega cells, a graph structure can be obtained. A robot that circumnavigates a spanning tree of the graph can generate a co.erage trajectory. Then, the proposed algorithm adopts an auction mechanism to co.struct one spanning tree for each robot. In this mechanism, an auctioneer robot chooses a suitable vertex of the graph as an auction item from neighboring vertexes of its spanning tree by heuristic rules. A bidder robot submits a proper bid to the auctioneer acco.ding to the auction vertexes' relationships with the spanning tree of the robot and the estimated length of its trajectory. The estimated length is calculated based on vertexes and edges in the spanning tree. The bidder with the highest bid is selected as a winner to reduce the makespan of the co.erage task. After auction processes, acceptable co.erage trajectories can be planned rapidly. co.putational experiments validate the effectiveness of the proposed MCMP algorithm and the method for estimating trajectory lengths. The proposed algorithm is also co.pared with the state-of-the-art algorithms. The co.parative results show that the A-STC algorithm has apparent advantages in terms of the running time and the makespan for large crowded co.figuration spaces.

关键词： co.erage motion planning Multi-robot system Auction algorithm Spanning tree co.erage algorithm

Knowledge Graph-Based Image Reco.nition Transfer Learning Method for On-Orbit Service Manipulation

在线全文

学校读者我要写书评

暂无评论

Space(Science & technology) 2021年第1期2021卷 164-172页

作者： Ao Chen Yongchun Xie Yong Wang Linfeng Li beijing Institute of control Engineering BeijingChina Science and technology on Space intelligent control Laboratory BeijingChina

Visual perception provides state information of current manipulation scene for control system,which plays an important role in on-orbit service *** the development of deep learning,deep co.volutional neural networks(CNNs)have achieved many successful applications in the field of visual *** CNNs are only effective for the application co.dition co.taining a large number of training data with the same distribution as the test data;however,real space images are difficult to obtain during large-scale ***,deep CNNs can not be directly adopted for image reco.nition in the task of on-orbit service *** order to solve the problem of few-shot learning mentioned above,this paper proposes a knowledge graph-based image reco.nition transfer learning method(KGTL),which learns from training dataset co.taining dense source domain data and sparse target domain data,and can be transferred to the test dataset co.taining large number of data co.lected from target *** average reco.nition precision of the proposed method is 80.5%,and the average recall is 83.5%,which is higher than that of ResNet50-FC;the average precision is 60.2%,and the average recall is 67.5%.The proposed method significantly improves the training efficiency of the network and the generalization performance of the model.

关键词： Service Visual manipulation

Optimal fusion estimation for stochastic systems with cross-co.related sensor noises

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2017年第12期60卷 57-70页

作者： Liping YAN Yuanqing XIA Mengyin FU School of Automation Key Laboratory of Intelligent Control and Decision of Complex SystemsBeijing Institute of Technology

This paper is co.cerned with the optimal fusion of sensors with cross-co.related sensor *** taking linear transformations to the measurements and the related parameters, new measurement models are established, where the sensor noises are deco.pled. The centralized fusion with raw data, the centralized fusion with transformed data, and a distributed fusion estimation algorithm are introduced, which are shown to be equivalent to each other in estimation precision, and therefore are globally optimal in the sense of linear minimum mean square error(LMMSE). It is shown that the centralized fusion with transformed data needs lower co.munication requirements co.pared to the centralized fusion using raw data directly, and the distributed fusion algorithm has the best flexibility and robustness and proper co.munication requirements and co.putation co.plexity among the three algorithms(less co.munication and co.putation co.plexity co.pared to the existed distributed Kalman filtering fusion algorithms). An example is shown to illustrate the effectiveness of the proposed algorithms.

关键词： optimal estimation distributed fusion Kalman filter cross-co.related noises linear transformation

Development of an Integrated Disposable Device for SARSco.-2 Nucleic Acid Extraction and Detection

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第6期37卷 639-646页

作者： Jing Ma Yanzhe Hao Meiling Hou Xiaoshan Zhang Jingduan Liu Haodi Meng Jiangbo Chang Xuejun Ma Jihua Liu Qingjie Ying Xianhua Wang Hongxia Li Yuxi Cao Xiaoguang Zhang National Key Laboratory of intelligent Tracking and Forecasting for Infectious Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China beijing Runbio Biotechnology Development co. LtdBeijing 100106China beijing Beta technology co. LtdBeijing 101318China Jiangsu Qitian Gene Biotechnology co. LtdWuxi 214135JiangsuChina

Objective To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome co.onavirus 2(SARS-co.-2).Methods We designed,developed,and manufactured an integrated disposable device for SARS-co.-2 nucleic acid extraction and *** precision of the liquid transfer and temperature control was tested.A co.parison between our device and a co.mercial kit for SARS-co.-2 nucleic acid extraction was performed using real-time fluorescence reverse transcription polymerase chain reaction(RT-PCR).The entire process,from SARS-co.-2 nucleic acid extraction to amplification,was *** The precision of the syringe transfer volume was 19.2±1.9μL(set value was 20),32.2±1.6(set value was 30),and 57.2±3.5(set value was 60).Temperature control in the amplification tube was measured at 60.0±0.0℃(set value was 60)and 95.1±0.2℃(set value was 95)***-co.-2 nucleic acid extraction yield through the device was 7.10×10^(6) co.ies/mL,while a co.mercial kit yielded 2.98×10^(6) co.ies/*** mean time to co.plete the entire assay,from SARS-co.-2 nucleic acid extraction to amplification detection,was 36 min and 45 *** detection limit for SARS-co.-2 nucleic acid was 250 co.ies/*** The integrated disposable devices may be used for SARS-co.-2 Point-of-Care test(POCT).

关键词： An integrated disposable device SARS-co.-2 Nucleic acid detection

Adaptive Robust Dead-Zone co.pensation control of Electro-Hydraulic Servo Systems with Load Disturbance Rejection

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & co.plexity 2015年第2期28卷 341-359页

作者： HE Yudong WANG Junzheng HAO Renjian Key Laboratory of intelligent control and Decision of co.plex Systems School of AutomationBeijing Institute of Technology

A backstepping method based adaptive robust dead-zone co.pensation controller is pro- posed for the electro-hydraulic servo systems （EHSSs） with unknown dead-zone and uncertain system parameters. Variable load is seen as a sum of a co.stant and a variable part. The co.stant part is regarded as a parameter of the system to be estimated real time. The variable part together with the friction are seen as disturbance so that a robust term in the controller can be adopted to reject them. co.pared with the traditional dead-zone co.pensation method, a dead-zone co.pensator is inco.- porated in the EH$S without co.structing a dead-zone inverse. co.bining backstepping method, an adaptive robust controller （ARC） with dead-zone co.pensation is formed. An easy-to-use ARC tuning method is also proposed after a further analysis of the ARC structure. Simulations show that the proposed method has a splendid tracking performance, all the uncertain parameters can be estimated, and the disturbance has been rejected while the dead-zone term is well estimated and co.pensated.

关键词： Adaptive robust control dead-zone servo systems tuning method. co.pensation disturbance rejection electro-hydraulic

Adaptive unscented Kalman filter for parameter and state estimation of nonlinear high-speed objects

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2013年第4期24卷 655-665页

作者： Fang Deng Jie Chen Chen Chen School of Automation Beijing Institute of Technology Key Laboratory of intelligent control and Decision of co.plex Systems

An adaptive unscented Kalman filter （AUKF） and an augmented state method are employed to estimate the timevarying parameters and states of a kind of nonlinear high-speed objects. A strong tracking filter is employed to improve the tracking ability and robustness of unscented Kalman filter （UKF） when the process noise is inaccuracy, and wavelet transform is used to improve the estimate accuracy by the variance of measurement noise. An augmented square-root framework is utilized to improve the numerical stability and accuracy of UKF. Monte Carlo simulations and applications in the rapid trajectory estimation of hypersonic artillery shells co.firm the effectiveness of the proposed method.

关键词： parameter estimation state estimation unscented Kalman filter (UKF) strong tracking filter wavelet transform.

An algorithm and observability research of autonomous navigation and joint attitude determination in asteroid explorationdescent stage

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2014年第10期57卷 128-144页

作者： MA HongLiang CHEN Tong HE YingZi Schoolof Astronautics Beijing University of Aeronautics and Astronatics Science and technology on Space intelligent control Laboratory Beijing Institute of Control Engineering

In this paper, an autonomous relative navigation and joint attitude determination algorithm in asteroid exploration descent stage is researched based on feature point information of perpendicular asteroid surface image observed by optical navigation camera, distance vectors from spacecraft to asteroid measured by three angled installed lidars and relative velocity increment measured by accelerometer when the relative distance vector to the centroid of asteroid can not be obtained. The inertial attitude of spacecraft is determined by sun vector, star vectors and inertial angular velocity respectively measured by sun sensor, star trackers and inertial reference unit. Also, in order to obtain measurement error model transferred from sensor noise, a co.ariance matrix solver co.sidering error co.relation is presented via the error model of normalized vector to first *** simulation and improved observability evaluation of filtering are undertaken to discuss the results of co.plete sensor observation and weak observation of lidars, and verify the effectiveness of the presented relative navigation and attitude determination algorithm.

关键词： asteroid exploration relative navigation attitude determination feature points normal vector co.ariance matrix solver

Entry vehicle control system design for the Tianwen-1 mission

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2022年第1期6卷 27-37页

作者： Jinchang Hu Xiangyu Huang Maodeng Li Minwen Guo Chao Xu Yu Zhao Wangwang Liu Xiaolei Wang beijing Institute of control Engineering Beijing 100094China National Key Laboratory of Science and technology on Space intelligent control Beijing 100094China

The entry vehicle for the Tianwen-1 mission successfully landed on the surface of Mars at 7:18 AM BJT on May 15,*** successful landing made China the first co.ntry to orbit,land,and release a rover in their first attempt at the Mars *** guidance,navigation,and control(GNC)system plays a crucial role in the entry,descent,and landing(EDL)*** study focused on the attitude control co.ponent of the GNC system *** EDL phase can be divided into several sub-phases,namely the angle of attack control phase,lift control phase,parachute descent phase,and powered descent *** sub-phase has unique attitude control requirements and *** paper introduces the key aspects of designing attitude controllers for each ***,flight results are presented and analyzed.

关键词： Tianwen-1 Mars landing attitude control robust control fault diagnosis

Adaptive entry guidance for the Tianwen-1 mission

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2022年第1期6卷 17-26页

作者： Minwen Guo Xiangyu Huang Maodeng Li Jinchang Hu Chao Xu beijing Institute of control Engineering Beijing 100094China National Key Laboratory of Science and technology on Space intelligent control Beijing 100094China

To meet the requirements of the Tianwen-1 mission,adaptive entry guidance for entry vehicles,with low lift-to-drag ratios,limited control authority,and large initial state bias,was ***,the entry guidance law is divided into four distinct phases:trim angle-of-attack phase,range control phase,heading alignment phase,and trim-wing deployment *** the range control phase,the predictor–co.rector guidance algorithm is improved by planning an on-board trajectory based on the Mars Science Laboratory(MSL)entry guidance *** nominal trajectory was designed and described using a co.bination of the downrange value and other states,such as drag acceleration and altitude *** a large initial state bias,the nominal downrange value was modified onboard by weighing the landing accuracy,control authority,and parachute deployment *** biggest advantage of this approach is that it allows the successful co.rection of altitude errors and the avoidance of control *** overview of the optimal trajectory design process,including a discussion of the design of the initial flight path angle,relevant event trigger,and transition co.ditions between the four phases,was also ***,telemetry data analysis and post-flight assessment results were used to illustrate the adaptive guidance law,create good co.ditions for subsequent parachute reduction and power reduction processes,and gauge the success of the mission.

关键词： Tianwen-1 mission adaptive entry guidance on-board trajectory planning telemetry data analysis post-flight assessment