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丘陵山地果园全液压遥控式履带动力底盘设计与试验

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农业机械学报 2024年第2期55卷 119-127,201页

作者：李善军陈辉龙彭际博孟亮张鑫李明震华中农业大学工学院武汉430070 农业农村部长江中下游农业装备重点实验室武汉430070

针对目前丘陵山地果园作业农用底盘整机体积大、行驶作业操作繁琐和通过性差等问题,结合丘陵山地果园开沟、除草和修剪等农艺管理环节的实际需求,设计了一款全液压遥控式履带动力底盘。首先,对动力底盘的整机结构和工作原理进行了阐述;... 详细信息

针对目前丘陵山地果园作业农用底盘整机体积大、行驶作业操作繁琐和通过性差等问题,结合丘陵山地果园开沟、除草和修剪等农艺管理环节的实际需求,设计了一款全液压遥控式履带动力底盘。首先,对动力底盘的整机结构和工作原理进行了阐述;其次,对前置挂载机构、行走系、变幅宽底盘、液压系统、遥控系统等关键部件进行设计和相应的匹配选型;最后,对整机进行了性能试验。试验结果表明:动力底盘在最小幅宽(1220 mm)和最大幅宽(1620 mm)的直线行驶偏移率分别为2.24%和2.2%,均满足相应国家标准(≤6%)要求。底盘的转向机动性能良好,最小幅宽原地转弯半径为905 mm,可适应丘陵山地果园相对狭窄的坡地作业环境。遥控操作上下斜坡、翻越田埂、跨越畦沟等过程平稳,满足丘陵山地果园非结构化地形行走要求。挂载链式开沟器进行开沟作业时,沟深稳定系数为88.5%,沟宽稳定系数为92.5%,满足国家标准(≥85%)要求。整机工作性能满足丘陵果园复杂坡度地形管理作业要求,可为丘陵山地果园田间管理作业的有效实施提供综合应用平台和技术支撑。

关键词：丘陵山地果园全液压驱动变幅宽履带动力底盘

丘陵果园自然环境下柑橘采摘机器人设计与试验

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农业机械学报 2024年第4期55卷 124-135页

作者：鲍秀兰马志涛马萧杰黎亦书任梦涛李善军华中农业大学工学院武汉430070 农业农村部长江中下游农业装备重点实验室武汉430070

智慧果园是未来果园行业发展的趋势,智能化果实采摘是发展智慧果园的关键问题。为实现智能化果实采摘,本文搭建了一种适用于丘陵果园矮化栽培模式下的柑橘采摘机器人系统。针对丘陵果园垄间地面凹凸不平,存在地形倾斜角0°~20°,设计了... 详细信息

智慧果园是未来果园行业发展的趋势,智能化果实采摘是发展智慧果园的关键问题。为实现智能化果实采摘,本文搭建了一种适用于丘陵果园矮化栽培模式下的柑橘采摘机器人系统。针对丘陵果园垄间地面凹凸不平,存在地形倾斜角0°~20°,设计了一种自适应调平平台保持机械臂基座水平;通过视觉系统获取多幅点云图像建立果树的三维点云模型,获取果实位置信息;为避免采摘时造成果实损伤,结合柑橘类水果的采摘特点,设计了一种剪切夹持一体化的末端执行器完成柑橘采摘。针对果园自然环境的主要扰动因素(风和光照)进行分级,设置10组对比试验,结果表明:在低光照或正常光照条件下,平均果实定位准确率为82.5%,末端执行器夹取成功率为87.5%,平均采摘时间最短为12.3 s/个;高光照条件下平均果实定位准确率为72%,末端执行器夹取成功率为80%,平均采摘时间最短为12.5 s/个。

关键词：柑橘采摘机器人三维点云模型自适应平台末端执行器

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柑橘木虱YOLO v8-MC识别算法与虫情远程监测系统研究

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农业机械学报 2024年第6期55卷 210-218页

作者：李善军梁千月余勇华陈耀晖付慧敏张宏宇华中农业大学工学院武汉430070 农业农村部长江中下游农业装备重点实验室武汉430070 广西桂北特色经济作物种质创新与利用重点实验室桂林541000 华中农业大学植物科学技术学院武汉430070

柑橘木虱是黄龙病的主要传播媒介,其发生与活动可对柑橘果园造成毁灭性后果。为实现木虱虫情的高效监测,设计了一种集诱捕拍照、耗材更新、害虫识别与结果展示于一体的智能监测系统。设计了具备诱虫胶带自动更新、虫情图像实时获取功能... 详细信息

柑橘木虱是黄龙病的主要传播媒介,其发生与活动可对柑橘果园造成毁灭性后果。为实现木虱虫情的高效监测,设计了一种集诱捕拍照、耗材更新、害虫识别与结果展示于一体的智能监测系统。设计了具备诱虫胶带自动更新、虫情图像实时获取功能的诱捕监测装置;应用选点裁剪、Mosaic数据增强(Mosaic data augmentation,MDA)和CA(Coordinate attention)注意力机制,改进了YOLO v8木虱识别模型;开发了Web和手机APP客户端,可实现虫情数据的可视化展示与远程控制。模型测试阶段,改进后的YOLO v8-MC召回率、F1值及精确率分别达到91.20%、91%、90.60%,较基准模型分别提升5.47、5、4.64个百分点;迁移试验中,模型召回率、F1值及精确率分别达到88.64%、87%、84.78%,且系统工作状态良好,满足野外使用需求。开发的智能监测系统能有效实现果园木虱虫情的远程监测,可为此类虫害防治管理提供有效手段。

关键词：柑橘木虱虫害监测诱捕监测装置 YOLO v8-MC

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Polymerization-induced phase separation in polyether-sulfone modified epoxy resin systems: effect of curing reaction mechanism

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Science China Chemistry 2007年第4期50卷 554-561页

作者： WANG MingHai YU YingFeng li shanjun The Key Laboratory of Molecular Engineering of Polymer Ministry of Education and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Polyethersulfone (PES)-modified epoxy systems with stepwise reaction were studied throughout the entire curing process by using optical microscopes, time-resolved light scattering (TRLS), and a rheolometry instrument compared with that of chainwise polymerization. The results suggested that the phase separation process is mainly controlled by the diffusion of epoxy oligomers for stepwise mechanism system and by that of epoxy monomers for chainwise mechanism system. In case of high PES content (SPES-20%) light-scattering results showed a viscoelastic phase separation and the characteristic relaxation time of phase separation can be described well by the WLF equation. However, in the case of low PES content (SPES-14%) secondary phase separation phenomenon was observed by Optical Microscope and further demonstrated by rheological study.

关键词： reaction mechanism phase separation viscoelastic effects

Effect of molecular weight on reaction-induced phase separation of epoxy resin modified with fluorocarbon chain terminated polyetherimide

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Science China Chemistry 2005年第6期48卷 560-566页

作者： GAN Wenjun li Hua HU Zhiqiang li liang li shanjun Key Laboratory of Molecular Engineering of Polymer Ministry of Education Department of Macromolecular ScienceFudan UniversityShanghai 200433China

A series of fluorocarbon chain terminated polyetherimide is added to epoxy resin,and the effect of molecular weight on the process of phase separation is studied by time-resolved light scattering(TRLS),differential scanning calorimeter(DSC),scanning microscopy(SEM).The results indicate that the phase separation rate decreases due to the preventing effect in-duced by low surface energy of fluorocarbon chain terminated *** addition,evolu-tion time of morphology is shortened and the domain size decreases with the introduction of fluorocarbon chain terminated ***,when the molecular weight of fluorocarbon chain terminated polyetherimide increases,the morphology can change from dis-persed phase to co-continuous ***,changing the molecular weight of fluorocarbon chain terminated polyetherimide can control the morphology of the epoxy/polyetherimide blend,which is of great significance in many industries.

关键词： fluorocarbon chain terminated polyetherimide epoxy molecular weight reaction-induced phase separa-tion time-resolved light scattering.

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猕猴桃大帐气调气流组织的数值模拟及优化

农业工程学报 2024年第5期40卷 307-316页

作者：徐勤超单程陈昊义朱家庭曾云流李善军潘海兵张文东华中农业大学工学院农业农村部长江中下游农业装备重点实验室武汉430070 华中农业大学园艺林学学院武汉430070 微呼吸(武汉)农业科技有限公司武汉430070

为确定合理的猕猴桃大帐气调参数,提高大帐气调贮藏性能,该研究通过模拟猕猴桃在果筐内的自然堆叠状态,建立了单个猕猴桃尺度的大帐气调微环境模型,采用数值模拟方法,分析猕猴桃大帐气调过程中N_(2)纯度、流量、管径、出口高度4个关键... 详细信息

为确定合理的猕猴桃大帐气调参数,提高大帐气调贮藏性能,该研究通过模拟猕猴桃在果筐内的自然堆叠状态,建立了单个猕猴桃尺度的大帐气调微环境模型,采用数值模拟方法,分析猕猴桃大帐气调过程中N_(2)纯度、流量、管径、出口高度4个关键参数对降氧时间及气体分布均匀性的影响。基于Box-Behnken原理设计四因素三水平正交仿真试验,利用Design-Expert软件建立响应指标回归模型,对所选取的4个因素进行响应面分析和参数优化。对优化参数组合进行仿真试验,对比优化参数组合条件下响应面回归模型预测值与仿真试验数值模拟值。结果表明:各因素对降氧时间影响由大到小顺序为出气口高度、流量、N_(2)纯度、管径;对不均匀系数影响由大到小顺序为N_(2)纯度、出气口高度、管径、流量。猕猴桃大帐气调的最优气调参数组合为N_(2)纯度96.0%、流量23.0 m^(3)/h、管径50 mm、出气口高度3 126 mm,对应的降氧时间、不均匀系数分别为989 s、6.1%。降氧时间响应面回归模型预测值与仿真值之间的相对误差为3.1%,不均匀系数响应面回归模型预测值与仿真值之间的相对误差为8.4%。研究对于大帐气调装备的研发及性能提升具有重要的理论和实际意义。

关键词：数值模拟响应面法贮藏气调性能大帐气调

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渗层强化的果园运输机驱动轮耐磨性能

农业工程学报 2024年第2期40卷 176-186页

作者：李善军牛成强万强贾槟源杨泽华彭际博罗银华中农业大学工学院武汉430070 农业农村部长江中下游农业装备重点实验室武汉430070 中船重工安谱仪器有限公司宜昌443003

为解决牵引式果园运输机绳-轮驱动系统驱动轮绳槽磨损严重而导致牵引滑移失效的问题,该研究对基于渗层强化的果园运输机驱动轮耐磨性能进行了分析。首先通过ANSYS软件探究了驱动轮表面应力应变随其硬度的变化规律;随后采用热扩散沉积(th... 详细信息

为解决牵引式果园运输机绳-轮驱动系统驱动轮绳槽磨损严重而导致牵引滑移失效的问题,该研究对基于渗层强化的果园运输机驱动轮耐磨性能进行了分析。首先通过ANSYS软件探究了驱动轮表面应力应变随其硬度的变化规律;随后采用热扩散沉积(thermal diffusion, TD)技术对45钢驱动轮进行了渗钒与渗硼处理,并对渗层的显微结构、力学性能和摩擦磨损特性进行了对比分析,最后利用运输机模拟台架对渗层强化后驱动轮的应用性能进行了测试。结果表明:驱动轮渗钒层和渗硼层厚度分别为20.9和97.3μm,均与基材结合较好;且由于渗层中碳化钒、硼化铁等硬质相的存在,渗钒层与渗硼层硬度分别达到22.08和13.45 GPa,较未处理前提升3~4倍;往复摩擦试验下渗钒层与渗硼层表面摩擦系数分别为0.47、0.44,较45钢分别下降19%、24%。运输机模拟台架应用性能测试表明,干摩擦下渗钒与渗硼处理后驱动轮的平均磨损量较45钢分别降低了88%和81%,其中渗钒驱动轮表面磨损较小;油润滑下渗钒与渗硼处理后驱动轮的平均磨损量较45钢分别降低了92%和85%。综上,热扩散渗钒与渗硼处理均可大幅提高驱动轮抗磨性,其中渗钒层具有更高的硬度与耐磨性,但在应用时需进行实时油润滑,更适合对满足定时维护条件下的驱动轮进行强化;而渗硼层耐磨性虽有所降低,但可在干摩擦下使用,更适合对野外山地环境下无法满足润滑的驱动轮进行强化。该研究结果可为改善牵引式果园运输机驱动轮耐磨性提供可行技术方案。

关键词：农业机械显微结构硬度渗层强化牵引式运输机驱动轮耐磨特性

Development and test of hydraulic driven remote transporter

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 72-80页

作者： Jiaxue li shanjun li Yanlin Zhang Mingdi liu Zhiyuan Gao College of Engineering Huazhong Agricultural UniversityWuhan 430070China Guangdong Polytechnic college Zhaoqing 526000GuangdongChina China Agriculture(Citrus)Research System Wuhan 430070China Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River Ministry of Agriculture and Rural AffairsWuhan 430070China Citrus Mechanization Research Base Ministry of Agriculture and Rural AffairsWuhan 430070China National R&D Center for Citrus Preservation Wuhan 430070China

To solve the problems of the traditional orchard conveyor,such as inflexible steering,a complex structure,poor stability and no power grid coverage,a remote-controlled rail conveyor powered by hydraulic pressure for mountainous orchards was designed and *** stress analysis was carried out on a full-load trailer to obtain the maximum traction force,which met the requirement of the climbing slope of the transport *** key components of the conveyor were developed,such as the hydraulic transmission,the control system,safety protection devices,limiting devices,the throttle and decompression actuator,the counterweight tension and the *** the theoretical calculations of key components,an orchard conveyor powered by diesel and hydraulic pressure was ***,the working performance of the transporter was tested through functionality,driving speed,system pressure and remote-controlled *** test results showed that the climbing angle of the transporter can reach 50°,the uphill load can reach 840 kg,the downhill load can reach 1100 kg,and the average running speed is 0.77 m/s;the driving speed ranges from 0.29 m/s to 1.08 m/s,and the system pressure ranges from 3.2 MPa to 10 *** driving speed and system pressure are significantly affected by the load,and the remote control distance can reach 455 *** technical specifications of the transporter meet all the design requirements,and the problem of stable operation of the transporter without power grid coverage has been *** research results can well meet the practical application requirements of mountain orchard transportation without power grid coverage and provide theoretical reference for the design of key components of mountain orchard transportation machinery.

关键词： mountain orchard conveyor hydraulic drive remote control

Development and tests of sliding contact line-powered track transporter

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 68-75页

作者： Yihua Jiang Fang Yang Zihao Zhang shanjun li College of Engineering Huazhong Agricultural UniversityWuhan 430070China China Agriculture(Citrus)Research System Wuhan 430070China National R&D Center for Citrus Preservation Wuhan 430070China Citrus Mechanization Research Base Ministry of Agriculture and Rural AffairsWuhan 430070China Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River Ministry of Agriculture and Rural AffairsWuhan 430070China

In order to solve the problems of complexity of control systems and the limited power supply of traditional fuelpowered and battery-driven transporters operating in mountainous orchards,a sliding contact line-powered track transporter was designed and manufactured based on theoretical *** components of the transporter were developed such as a PLC-based(programmable logic controller)control system,a sliding contact power supply,and transmission system,and a position limit *** functions and performance of designed transporter were *** test results showed that the transporter exhibited a high stability of operation with an average operation velocity of 0.70 m/s,the maximum working slope of 48°,the maximum load of 400 kg,and the maximum remote control distance reaching 1482 *** the power supply circuit of sliding contact line was 108.8 m in length,the maximum voltage drop was 2.4 V,and the maximum power loss was 174.72 W,which were close to the theoretical calculation *** a single power supply cabinet,the transporter can operate normally for a maximum track distance of 175.69 *** the technical indicators of the transporter met the design requirements,and the above-mentioned problems such as complexity of the control system and limited energy supply of the traditional mountain orchard transporter were well *** study can provide reference for the design and optimization of mountain orchard transporter.

关键词： mountain orchard transporter remote control sliding contact line voltage drop