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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:7
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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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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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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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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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JR East aims for driverless Shinkansen operation
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作者 Yasuaki Suzuki 《High-Speed Railway》 2024年第3期197-201,共5页
East Japan Railway Company(JR East)is aiming to“realize driverless train operation”as one of the key measures to respond to rapid changes in the business environment.Currently,Automatic Train Operation(ATO)equipment... East Japan Railway Company(JR East)is aiming to“realize driverless train operation”as one of the key measures to respond to rapid changes in the business environment.Currently,Automatic Train Operation(ATO)equipment is not installed on the Shinkansen,but there are plans to introduce ATO or driverless operation in the near future.From 2018-2021,the Ministry of Land,Infrastructure,Transport and Tourism(MLIT)held the“ATO Technology Study Group for Railways”in which the concept of technical requirements necessary for driverless operation was discussed.In 2021,JR East conducted the GOA4 demonstration test on the Joetsu Shinkansen.In this test,we were able to confirm the basic functions of Shinkansen vehicles such as automatic departure control,speed control,fixed position stop control,and remote stop control using ATO.We aim to realize unattended operation(GOA4)for deadhead trains between Niigata Station and the Niigata Shinkansen Rolling Stock Center by the end of the 2020 s,and driverless operation(GOA3)for passenger trains of the Joetsu Shinkansen by the mid-2030s and continue to develop the necessary technologies and build systems. 展开更多
关键词 High-speed railway SHINKANSEN ATO automatic train operation GOA3 Driverless operation
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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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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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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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FAO信号系统测试方案的探讨与研究 被引量:1
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作者 刘斌 焦凤霞 《铁路通信信号工程技术》 2024年第7期97-103,共7页
针对城市轨道交通FAO信号系统技术要求高、接口关系复杂等特点,结合FAO信号系统上云等最新技术发展趋势,对标欧标,采用“V”模型周期控制方法,提出FAO信号系统的测试方案,分析各阶段的测试目的、测试平台及测试内容,为FAO项目如期全功... 针对城市轨道交通FAO信号系统技术要求高、接口关系复杂等特点,结合FAO信号系统上云等最新技术发展趋势,对标欧标,采用“V”模型周期控制方法,提出FAO信号系统的测试方案,分析各阶段的测试目的、测试平台及测试内容,为FAO项目如期全功能开通提供一种测试方法的指导和借鉴。 展开更多
关键词 城市轨道交通 全自动运行系统 信号系统 测试方法
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基于FMEA的FAO自动唤醒功能安全设计与实现
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作者 贾佳 《铁路通信信号工程技术》 2024年第6期84-88,95,共6页
采用FMEA的分析方法对全自动无人驾驶列车自动唤醒功能进行深入研究,分析可能产生危险后果的失效模式以及对应的失效原因,并结合失效模式和失效原因设计相应的安全措施,保证全自动无人驾驶系统将系统原有风险以及新增功能引发的风险均... 采用FMEA的分析方法对全自动无人驾驶列车自动唤醒功能进行深入研究,分析可能产生危险后果的失效模式以及对应的失效原因,并结合失效模式和失效原因设计相应的安全措施,保证全自动无人驾驶系统将系统原有风险以及新增功能引发的风险均减轻至可接受程度,真正实现安全可靠的运行。 展开更多
关键词 全自动无人驾驶 自动唤醒 安全分析 安全设计 FMEA
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智慧城轨FAO模式下的职业院校人才培养路径研究 被引量:1
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作者 李桃 《中国现代教育装备》 2024年第3期167-169,181,共4页
FAO技术在减员增效、节能环保、全面提升城市轨道交通运营自动化水平方面具有诸多优势,代表了未来城市轨道交通发展的方向。在智慧城轨FAO模式下,城市轨道交通运营企业现有各专业细分的运营管理人员,将向全面、综合、高素质的人才队伍转... FAO技术在减员增效、节能环保、全面提升城市轨道交通运营自动化水平方面具有诸多优势,代表了未来城市轨道交通发展的方向。在智慧城轨FAO模式下,城市轨道交通运营企业现有各专业细分的运营管理人员,将向全面、综合、高素质的人才队伍转变,人才供给将出现很大缺口。基于智慧城轨FAO模式,分析了职业院校人才培养的新需求,从搭建校企合作平台、优化课程体系结构、建设教学支撑体系和创新混合式教学模式方面提出了人才培养路径,为职业院校与城市轨道交通运营企业培养所需人才提供了切实可行的具体方法。 展开更多
关键词 智慧城轨 全自动运行 职业院校 人才培养
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具有避障功能的农机自动作业全覆盖路径规划方法
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作者 罗荣浩 干熊 杨光友 《农机化研究》 北大核心 2025年第2期36-43,共8页
针对不同尺寸和类型障碍物条件下的农机车辆自动作业全覆盖路径规划问题,提出了静态全覆盖路径规划方法和路径优化方案。根据矩形田块信息、障碍物信息、农机最小转弯半径和机具宽度,自动选定作业方向、作业行距、地头转弯区域和转弯模... 针对不同尺寸和类型障碍物条件下的农机车辆自动作业全覆盖路径规划问题,提出了静态全覆盖路径规划方法和路径优化方案。根据矩形田块信息、障碍物信息、农机最小转弯半径和机具宽度,自动选定作业方向、作业行距、地头转弯区域和转弯模式等参数;根据障碍物形状、高覆盖率高作业路径比的需求,对算法进行优化调整,以达到更好的作业效果。软件仿真测试结果表明:对有小矩形障碍物的田块,改进后的算法覆盖率提升了0.11%,重复率降低了0.71%;对大矩形障碍物的田块,两种分区路径的覆盖率分别为89.24%和98.08%,重复率分别为3.53%和2.84%。研究结果表明:算法提高了田块的利用率,降低了作业成本,能够有效避开大小障碍物,同时满足高覆盖率和低重复率的田间作业要求。 展开更多
关键词 农机车辆 路径规划算法 自动作业 避障
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