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Automatic Driving Operation Strategy of Urban Rail Train Based on Improved DQN Algorithm
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作者 Tian Lu Bohong Liu 《Journal on Artificial Intelligence》 2023年第1期113-129,共17页
To realize a better automatic train driving operation control strategy for urban rail trains,an automatic train driving method with improved DQN algorithm(classical deep reinforcement learning algorithm)is proposed as... To realize a better automatic train driving operation control strategy for urban rail trains,an automatic train driving method with improved DQN algorithm(classical deep reinforcement learning algorithm)is proposed as a research object.Firstly,the train control model is established by considering the train operation requirements.Secondly,the dueling network and DDQN ideas are introduced to prevent the value function overestimation problem.Finally,the priority experience playback and“restricted speed arrival time”are used to reduce the useless experience utilization.The experiments are carried out to verify the train operation strategy method by simulating the actual line conditions.From the experimental results,the train operation meets the ATO requirements,the energy consumption is 15.75%more energy-efficient than the actual operation,and the algorithm convergence speed is improved by about 37%.The improved DQN method not only enhances the efficiency of the algorithm but also forms a more effective operation strategy than the actual operation,thereby contributing meaningfully to the advancement of automatic train operation intelligence. 展开更多
关键词 DQN algorithm automatic train operation(ATO) operation strategy urban rail train
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High-Speed Trains Automatic Operation with Protection Constraints: A Resilient Nonlinear Gain-based Feedback Control Approach 被引量:2
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作者 Shigen Gao Yuhan Hou +2 位作者 Hairong Dong Sebastian Stichel Bin Ning 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期992-999,共8页
This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of gua... This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of guaranteeing,under some proper non-restrictive initial conditions,the protection constraints control raised by the distance-to-go(moving authority)curve and automatic train protection in practice.A new hyperbolic tangent function-based model is presented to mimic the whole operation process of high-speed trains.The proposed feedback control methods are easily implementable and computationally inexpensive because the presence of only two feedback gains guarantee satisfactory tracking performance and closed-loop stability,no adaptations of unknown parameters,function approximation of unknown nonlinearities,and attenuation of external disturbances in the proposed control strategies.Finally,rigorous proofs and comparative simulation results are given to demonstrate the effectiveness of the proposed approaches. 展开更多
关键词 automatic TRAIN operation high-speed TRAIN nonlinear GAIN feedback PROTECTION CONSTRAINT resilient control
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Automatic Extraction of Urban Road Centerlines from High-Resolution Satellite Imagery Using Automatic Thresholding and Morphological Operation Method 被引量:6
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作者 Abdur Raziq Aigong Xu Yu Li 《Journal of Geographic Information System》 2016年第4期517-525,共9页
The commercial high-resolution imaging satellite with 1 m spatial resolution IKONOS is an important data source of information for urban planning and geographical information system (GIS) applications. In this paper, ... The commercial high-resolution imaging satellite with 1 m spatial resolution IKONOS is an important data source of information for urban planning and geographical information system (GIS) applications. In this paper, a morphological method is proposed. The proposed method combines the automatic thresholding and morphological operation techniques to extract the road centerline of the urban environment. This method intends to solve urban road centerline problems, vehicle, vegetation, building etc. Based on this morphological method, an object extractor is designed to extract road networks from highly remote sensing images. Some filters are applied in this experiment such as line reconstruction and region filling techniques to connect the disconnected road segments and remove the small redundant. Finally, the thinning algorithm is used to extract the road centerline. Experiments have been conducted on a high-resolution IKONOS and QuickBird images showing the efficiency of the proposed method. 展开更多
关键词 automatic Thresholding High-Resolution Imagery Morphological operation Posts Processing Thinning Algorithm Urban Road Centerlines Extraction
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Discussion on the Design of E-commerce Automatic Operation Module
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作者 Qian Wang Mingke Gao 《International English Education Research》 2014年第6期60-61,共2页
E-commerce refers to a kind of business and trade activities, which are conducted under the situation that buyers and sellers do not meet each other by using a fast, easy and low-cost way. Along with the promotion and... E-commerce refers to a kind of business and trade activities, which are conducted under the situation that buyers and sellers do not meet each other by using a fast, easy and low-cost way. Along with the promotion and application of computer office automation, it is necessary for e-commerce module to develop towards automation, in which the core lies in making a good design for operation module. In this paper, the promotion of e-commerce in the information age is reviewed by the authors, the unique characteristics of e-commerce functional modules are analyzed, and also the most important point of the design of e-commerce automatic operation module is discussed. Hopefully, helps can be provided for relevant follow-up studies in the future. 展开更多
关键词 E-COMMERCE automatic operation Module DESIGN
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Discussion on the Design of E-commerce Automatic Operation Module
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作者 Qian Wang Mingke Gao 《International English Education Research》 2014年第7期102-103,共2页
E-commerce refers to a kind of business and trade activities, which are conducted under the situation that buyers and sellers do not meet each other by using a fast, easy and low-cost way. Along with the promotion and... E-commerce refers to a kind of business and trade activities, which are conducted under the situation that buyers and sellers do not meet each other by using a fast, easy and low-cost way. Along with the promotion and application of computer office automation, it is necessary for e-commerce module to develop towards automation, in which the core lies in making a good design for operation module. In this paper, the promotion of e-commerce in the information age is reviewed by the authors, the unique characteristics of e-commerce functional modules are analyzed, and also the most important point of the design of e-commerce automatic operation module is discussed. Hopefully, helps can be provided for relevant follow-up studies in the future. 展开更多
关键词 E-COMMERCE automatic operation Module DESIGN
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Research on Operation Safety of Urban Rail Transit Based on Automatic Ticket Checking(AFC)System
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作者 Yao Tong 《时代汽车》 2021年第3期196-197,共2页
At present,after the actual inspection of the rail transit automatic ticket checking system,some security vulnerabilities have appeared,and there are also some defects in information security.For example,the database ... At present,after the actual inspection of the rail transit automatic ticket checking system,some security vulnerabilities have appeared,and there are also some defects in information security.For example,the database and virus protection need to be analyzed and upgraded in order to cope with the increasing number of information security risks.This article analyzes the security problems in the AFC system,and puts forward related suggestions and solutions,hoping to provide some reference for technical developers. 展开更多
关键词 rail transit automatic ticket inspection system operational safety
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Discussion on the Design of E-commerce Automatic Operation Module
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作者 Qian Wang MingkeGao 《Journal of Zhouyi Research》 2014年第5期87-88,共2页
关键词 电子商务 功能模块 自动操作 设计 办公自动化 自动化操作 贸易活动 信息时代
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Analysis on Operational Safety and Efficiency of FAO System in Urban Rail Transit
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作者 Kaige Guo Jin Zhou +3 位作者 Xiaoming Zhang Di Sun Zishuo Wang Lixian Zhao 《Computers, Materials & Continua》 SCIE EI 2023年第12期3677-3696,共20页
This paper discusses two urgent problems that need to be solved in fully automatic operation(FAO)for urban rail transit.The first is the analysis of safety in FAO,while another is the analysis of efficiency in FAO.Fir... This paper discusses two urgent problems that need to be solved in fully automatic operation(FAO)for urban rail transit.The first is the analysis of safety in FAO,while another is the analysis of efficiency in FAO.Firstly,this paper establishes an operational safety evaluation index system from the perspective of operation for the unique or typical risk sources of the FAO system,and uses the analytic hierarchy process(AHP)to evaluate the indicators,analyzes various factors that affect the safe operation of FAO,and provides safety management recommendations for FAO lines operation to maintain the FAO system specifically.Secondly,taking the Yanfang Line as an example,this paper uses OpenTrack software to analyze the efficiency of FAO operation,and conducts simulation calculations for key links such as the mainline tracking interval,train entry and exit,and return limit interval.The fault impact surface of the FAO trains is simulated and discussed to verify whether FAO can meet the long-term operation requirements of Yanfang Line.Finally,this paper compares the simulation data of FAO on the Yanfang Line with manual operation(MO)to verify the advantages of FAO and guide the engineering construction of subsequent fully automated driving lines. 展开更多
关键词 Fully automatic operation safety analysis efficiency analysis OpenTrack simulation
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Braking distance prediction for vehicle consist in low-speed on-sight operation:a Monte Carlo approach
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作者 Raphael Pfaff 《Railway Engineering Science》 2023年第2期135-144,共10页
The first and last mile of a railway journey, in both freight and transit applications, constitutes a high effort and is either non-productive(e.g. in the case of depot operations) or highly inefficient(e.g. in indust... The first and last mile of a railway journey, in both freight and transit applications, constitutes a high effort and is either non-productive(e.g. in the case of depot operations) or highly inefficient(e.g. in industrial railways). These parts are typically managed on-sight, i.e. with no signalling and train protection systems ensuring the freedom of movement. This is possible due to the rather short braking distances of individual vehicles and shunting consists. The present article analyses the braking behaviour of such shunting units. For this purpose, a dedicated model is developed. It is calibrated on published results of brake tests and validated against a high-definition model for lowspeed applications. Based on this model, multiple simulations are executed to obtain a Monte Carlo simulation of the resulting braking distances. Based on the distribution properties and established safety levels, the risk of exceeding certain braking distances is evaluated and maximum braking distances are derived. Together with certain parameters of the system, these can serve in the design and safety assessment of driver assistance systems and automation of these processes. 展开更多
关键词 Freight rail SHUNTING Braking curves Brake set-up Driver assistance system automatic train operation
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Variable-mass Thermodynamics Calculation Model for Gas-operated Automatic Weapon
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作者 陈建彬 吕小强 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第4期217-223,共7页
Aiming at the fact that the energy and mass exchange phenomena exist between barrel and gas-operated device of the automatic weapon, for describing its interior ballistics and dynamic characteristics of the gas-operat... Aiming at the fact that the energy and mass exchange phenomena exist between barrel and gas-operated device of the automatic weapon, for describing its interior ballistics and dynamic characteristics of the gas-operated device accurately, a new variable-mass thermodynamics model is built. It is used to calculate the automatic mechanism velocity of a certain automatic weapon, the calculation results coincide with the experimental results better, and thus the model is validated. The influences of structure parameters on gas-operated device's dynamic characteristics are discussed. It shows that the model is valuable for design and accurate performance prediction of gas-operated automatic weapon. 展开更多
关键词 MECHANICS automatic weapon variable-mass thermodynamics gas-operated device COUPLING modeling and simulation
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A new approach for classification of human brain CT images based on morphological operations 被引量:1
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作者 Ali Reza Fallahi Mohammad Pooyan Hassan Khotanlou 《Journal of Biomedical Science and Engineering》 2010年第1期78-82,共5页
Automatic diagnosis may help to decrease human based diagnosis error and assist physicians to focus on the correct disease and its treatment and to avoid wasting time on diagnosis. In this paper computer aided diagnos... Automatic diagnosis may help to decrease human based diagnosis error and assist physicians to focus on the correct disease and its treatment and to avoid wasting time on diagnosis. In this paper computer aided diagnosis is applied to the brain CT image processing. We compared performance of morphological operations in extracting three types of features, i.e. gray scale, symmetry and texture. Some classifiers were applied to classify normal and abnormal brain CT images. It showed that morphological operations can improve the result of accuracy. Moreover SVM classifier showed better result than other classifiers. 展开更多
关键词 CT IMAGE FEATURE EXTRACTION CLASSIFICATION MORPHOLOGICAL operations automatic DIAGNOSIS
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Conceptual Architecture for Remotely Piloted Operation Mode in Commercial Aircraft 被引量:1
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作者 LUO Yue WANG Miao +1 位作者 XIAO Gang WANG Guoqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第2期274-287,共14页
With the increasing civil aviation passengers and the rapid development of aviation logistics,the study on remotely piloted operation(RPO)mode has received extensive attention.RPO mode constructs the piloting decision... With the increasing civil aviation passengers and the rapid development of aviation logistics,the study on remotely piloted operation(RPO)mode has received extensive attention.RPO mode constructs the piloting decisionmaking mode which involves the tripartite collaboration among airborne automatic/autonomous system,remote ground-based crews and air traffic control.In this paper,we describe the organizing architecture for commercial remotely piloted aircraft(CRPA)system and its components.Compared with the current operation mode,the new air-ground collaborative decision-making mode has been established with six different situations based on the type of the flight and the condition of the remote pilot.Taking airport surface operation as an experimental example,we model the airport surface operation process and compare the advantages and disadvantages between RPO mode and the current dual-pilot mode from the perspectives of time and operation coverage,and draw conclusions that RPO mode can basically cover the flight operations of the dual-pilot,improve the accuracy of pilot operations and greatly reduce response time by 48%in pre-flight inspection.The above research would be the foundation for the RPO development of commercial aircraft in China. 展开更多
关键词 remotely piloted operations(RPO) commercial remotely piloted aircraft(CRPA) airborne automatic/autonomous system flight process
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Control Strategy and Expert System for Jig Operation
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作者 刘文礼 符东旭 《International Journal of Mining Science and Technology》 SCIE EI 1999年第1期29-32,共4页
On the basis of the first jig separation stage, the relational mathematical model related to ash content and the coutent of coal gangue with a density less than 1. 8 g/cm3 is established. With this model, the discharg... On the basis of the first jig separation stage, the relational mathematical model related to ash content and the coutent of coal gangue with a density less than 1. 8 g/cm3 is established. With this model, the discharge rate of reruse can be adjusted automatically and exactly by the conveutional PI regulator.The control stratedes for water capacity, air pressure, and feed capacity of the jig are introduced.Combined with the Expert system technology, jig expert system (JEP) is developed. 展开更多
关键词 JIG operation model automatic CONTROL STRATEGY EXPERT system
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Design of Automatic Quasi-synchronizing Device in Rural Small Hydropower Station
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作者 LI Anxiang ZHAO Yulin LIU Jihong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第4期60-64,共5页
Generator synchronization is an important and frequent operation in rural small hydropower station. In order to ensure that generator can be paralleled in the grid automatically, efficiently, and stably in the rural s... Generator synchronization is an important and frequent operation in rural small hydropower station. In order to ensure that generator can be paralleled in the grid automatically, efficiently, and stably in the rural small hydropower station whose parallel in operation still needs to be accomplished manually. This paper described an automatic quasi-synchronizing device, based on 89C52 Single-chip Microcomputer (SCM). Its hardware includes three modules and its software is structuralized. The device structure is simple, and its reliability is high and the maintenance is easy. Besides, convenient Human Machine Interface (HMI) makes the parameter setting simple and flexible 展开更多
关键词 automatic quasi-synchronizing parallel in operation voltage difference frequency difference phase difference
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Energy Saving for Automatic Train Control in Moving Block Signaling System
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作者 GU Qing MENG Yu MA Fei 《China Communications》 SCIE CSCD 2014年第A02期12-22,共11页
With rapid development of the railway traffic, the moving block signaling system (MBS) method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway ... With rapid development of the railway traffic, the moving block signaling system (MBS) method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway while maintaining the required safety margins. In this framework, the tracking target point of the following train is moving forward with its leading train. This paper focuses on the energy saving tracking control of two successive trains in MBS. Nonlinear programming method is used to optimize the energy-saving speed trajectory of the following train. The real-time location of the leading train could be integrated into the optimization process. Due to simplicity, it can be used for online implementation. The feasibility and effectiveness are verified through simulation. The results show that the new method is efficient on energy saving even when disturbances present. 展开更多
关键词 moving block signaling (MBS) energy saving automatic train protection (ATP) automatic train operation (ATO) TRACKING train speed trajectory
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机器人人工拣选环境下混流装配线齐套物料配送优化 被引量:1
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作者 周晓晔 马小云 朱梅琳 《计算机集成制造系统》 EI CSCD 北大核心 2024年第4期1527-1536,共10页
为了提高汽车制造企业配送的智能化水平、解决混流装配线齐套物料人工拣选效率低、成本高的问题,引入基于齐套物料配送策略的机器人人工拣选模式,通过优化自动拣选机器人、工人的配置数量及配送周期,使包含机器人使用成本、劳动力成本... 为了提高汽车制造企业配送的智能化水平、解决混流装配线齐套物料人工拣选效率低、成本高的问题,引入基于齐套物料配送策略的机器人人工拣选模式,通过优化自动拣选机器人、工人的配置数量及配送周期,使包含机器人使用成本、劳动力成本和在制品库存成本在内的总成本最小。为求解该配送优化问题,提出了改进量子蚁群算法,利用量子比特的叠加性增加种群多样性,避免算法陷入局部最优,同时设计了改进量子旋转门更新机制和基于差分进化操作的非最优个体优化策略,提高了算法收敛速度和寻优质量。最后,通过算例分析验证了模型的正确性与算法的有效性,并分析了拣选批量对总成本的影响。 展开更多
关键词 机器人人工拣选 齐套配送策略 混流装配线 自动拣选机器人 改进量子蚁群算法
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数字孪生下的液压缸机械运行位置自动控制 被引量:1
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作者 陈珩 《自动化与仪表》 2024年第1期24-29,共6页
液压缸机械系统非线性特征复杂,机械运行行为特征不明确,位置控制结果存在偏差,对此,该文提出数字孪生下的液压缸机械运行位置自动控制方法。连续检测液压缸机械系统运行状态,构建非线性状态方程,对比实际测量数据与输出数据的差异,选取... 液压缸机械系统非线性特征复杂,机械运行行为特征不明确,位置控制结果存在偏差,对此,该文提出数字孪生下的液压缸机械运行位置自动控制方法。连续检测液压缸机械系统运行状态,构建非线性状态方程,对比实际测量数据与输出数据的差异,选取RBF核函数与支持向量机,机械运行位置变化量,描述机械运行行为特征,建立位置控制目标函数,将最高适应度值对应的位置点自动更新为副本位置点,引入猫群算法求解目标函数,对位置控制目标函数的全局最优解展开更新,实现液压缸机械运行位置自动控制。实验结果表明,所提方法应用后,位移检测曲线与实际位移曲线之间的偏差较小,且在恒负载工况下和变负载工况下,位移稳态误差均较小,说明其机械运行位置自动控制结果精度高、控制效率高、控制精度高。 展开更多
关键词 数字孪生技术 液压缸 机械运行位置 自动控制 RBF核函数
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基于改进蚁群算法的自动落布车路径规划 被引量:1
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作者 沈丹峰 王博 +1 位作者 李许锋 白鹏飞 《西安工程大学学报》 CAS 2024年第1期50-59,共10页
针对自动落布车在使用蚁群算法(ant colony algorithm,ACA)进行路径规划过程中出现的收敛次数多、收敛速度较慢且容易陷入局部最优的问题,提出一种改进蚁群算法(improved ant colony algorithm,IACA)。首先对信息素挥发系数ρ进行自适... 针对自动落布车在使用蚁群算法(ant colony algorithm,ACA)进行路径规划过程中出现的收敛次数多、收敛速度较慢且容易陷入局部最优的问题,提出一种改进蚁群算法(improved ant colony algorithm,IACA)。首先对信息素挥发系数ρ进行自适应调整,令其做动态变化,克服算法的收敛次数过多,加快算法收敛速度,减少算法的收敛时间;其次引入细菌觅食算法中趋化操作的趋化步长因子对信息素更新公式进行改进,削减算法迭代的后期信息素浓度值,使算法在后期跳出局部最优值,提高算法全局搜索能力。利用MATLAB将改进后的算法在3种不同的栅格环境中进行仿真验证。结果表明:相比传统蚁群算法,改进后的算法收敛次数减少81.1%,最小路径长度减少6.3%,收敛时间减少20.7%。最后搭建ROS小车实验平台,利用ROS机器人系统对改进蚁群算法在模拟的织布车间环境中进行实验验证。结果表明:对比传统蚁群算法,改进蚁群算法在寻优时间上减少了8.6%。 展开更多
关键词 自动落布车 蚁群算法 信息素挥发系数 自适应调整 细菌觅食算法 趋化操作
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具有未知时变参数城轨列车的精准停车鲁棒控制
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作者 李茂青 朱胜杰 +2 位作者 林俊亭 高云波 岳丽丽 《铁道学报》 EI CAS CSCD 北大核心 2024年第7期65-72,共8页
列车运行情况复杂多变,使得列车质量、基本运行阻力及线路状况等参数难以精确获得且随着列车运行存在明显的时变特性。列车模型参数的不确定性和时变特性会对列车的精准停车性能产生重要的影响。在动车组多质点动力学模型的基础上,根据L... 列车运行情况复杂多变,使得列车质量、基本运行阻力及线路状况等参数难以精确获得且随着列车运行存在明显的时变特性。列车模型参数的不确定性和时变特性会对列车的精准停车性能产生重要的影响。在动车组多质点动力学模型的基础上,根据Lyapunov再设计方法设计了一种非线性列车鲁棒控制器。该控制器将系统中的不确定性因素视为等价干扰,并设计相应的鲁棒补偿项。根据参数的先验区间,设计的鲁棒补偿项能够抑制模型估计误差,使得列车的位置和速度跟踪误差快速收敛,最终实现精准停车的控制目标;同时,也证明了系统的最终一致有界稳定性。最后,选取城市轨道交通场景进行仿真验证,仿真结果表明:本文提出的控制方法在列车模型参数未知且时变情景下也能实现对期望停车曲线的快速、精确追踪,表现出较强的鲁棒特性。 展开更多
关键词 列车自动运行 多质点模型 精准停车 鲁棒控制 未知时变参数 最终一致稳定性
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89钻杆自动排放机械手设计与研究
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作者 张嘉钰 杨佳俊 +1 位作者 杨晨虎 牛虎利 《河北工业科技》 CAS 2024年第4期313-320,共8页
为了解决目前人工辅助完成陆地钻台立柱存取存在排放工作劳动强度大、安全性低等问题,以KV3000钻井平台为大环境、89钻杆组成的立柱为研究对象,设计了钻杆自动排杆机械手。首先,对钻井过程中存取立柱的动作及时序过程进行分析;其次,采... 为了解决目前人工辅助完成陆地钻台立柱存取存在排放工作劳动强度大、安全性低等问题,以KV3000钻井平台为大环境、89钻杆组成的立柱为研究对象,设计了钻杆自动排杆机械手。首先,对钻井过程中存取立柱的动作及时序过程进行分析;其次,采用动力学仿真分析方法对自动排放机械手进行干涉检查和行程检验,并针对核心零部件进行有限元分析。结果表明:研究装置可顺利完成钻杆存取工作,实现立柱在立柱盒与井口之间的位置转换,加速度均为线性,变化比较平稳,整体无较大波动;核心零部件最大变形为0.15167 mm,最大应力为59.875 MPa,均在允许范围。设备结构合理、运动轨迹规划合理、核心受力部件满足使用要求,提高了钻井作业过程中的自动化程度和安全性,为钻井作业钻杆自动排放提供了解决方案。 展开更多
关键词 工业机器人技术 机械手 自动排杆 结构设计 动力学仿真 钻井作业
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