Assessment of BRRI Whole Feed Combine Harvester (Model BRRI WCH2021) for Mechanized Rice Harvesting in Bangladesh

Agricultural mechanization plays a pivotal role in the transition from subsistence to commercial agriculture, with a particular focus on labour-intensive activities like harvesting. This study assesses the operational characteristics of the BRRI Whole Feed Combine Harvester (Model BRRI WCH2021) at the field level. Developed under the SFMRA project, the harvester’s technical performance and loss assessment were conducted during the Boro 2022 and Aman 2022 seasons in farmer fields in Bangladesh’s Rangpur region. The field efficiency of the harvester was determined to be 62.5% and 57.9% in the Boro and Aman seasons, respectively. Fuel consumption rates were recorded at 2.77 l/ha and 2.31 l/ha for the Boro and Aman seasons. The total harvesting losses, encompassing cutter bar, shatter, cylinder, and separation loss, averaged 0.56% and 0.48% in the Boro and Aman seasons, respectively. Mechanized harvesting with the BRRI Whole Feed Combine Harvester significantly reduced paddy losses by 5.81% compared to manual methods. The field evaluation results indicate the combine harvester’s satisfactory performance, highlighting its potential to alleviate labour demands during peak harvesting. The development of the BRRI WCH offers a sustainable solution for rice harvesting mechanization among progressive farmers. It paves the way for the broader adoption of advanced agricultural technology in Bangladesh.

Combine Harvester: Small Machine Solves Big Rice Harvesting Problem of Bangladesh

Bangladesh, a country with 87% of rural households that depend on agriculture and rice dominated diets (70%), engages the country’s food security. Therefore, there is strong advocacy for a mechanized paddy harvesting system for food security in South Asia, mainly Bangladesh. Some harvesting machinery is available;however, the precise roles of a combine harvester during this process are little. This study attempts to understand the consequences of combining harvesters for paddy harvesting and compare them with hand harvesting. For comparison of field performance of combine harvester with traditional harvesting, the experiment was conducted at Gazipur District, Bangladesh, in 2016. Results showed that the labor required for harvesting unit area 283, 15 and 9.87 man-h∙ha−1 for T1 (Sickle + Head carry + Beating + Kula), T2 (Reaper + Trolley carry + Close drum thresher + winnower), T3 (Combine harvester) system, respectively. Likewise, the harvesting costs were 1.84 (T2) and 2.5 (T1) times higher than the combine harvester (T3). Also, the postharvest loss can be saved 1.84%, to use combine harvester over manual harvesting of paddy. The above result revealed that the semi-mechanized and mechanized harvesting system is a time, labor and cost-saving system;however, the manual reaping system is concerned with more postharvest losses (3.09%). This study highlights the importance of combine harvester;however, further research is required in other places with large and mini-combine harvesters under diverse cropping areas and to test a combine harvester’s detailed potentiality.

Optimization of Conventional Combine Harvester to Reduce Combine Losses for Basmati Rice (<i>Oryza Sativa</i>)

A study was conducted at PAU Regional Research Station, Gurdaspur (Punjab) to investigate the design and operational parameters of threshing mechanism of conventional combine harvester for basmati crop. This study was aimed to investigate the suitable changes required in the self-propelled conventional combine harvester for harvesting the basmati crop with minimum grain losses. Field evaluation of experiment was carried out to assess the influence of independent design variable i.e., arrangement of spikes (AS) and independent operational parameters such as concave clearance (CC) and cylinder speed (CS). The study was aimed to enumerate various combining losses viz., extent of visible and invisible grain damage and threshing efficiency at different AS, CC and CS levels. The first year data recorded during 2017 were processed for the optimization during 2018. The results of the present study revealed that during 2017, maximum visible and invisible losses was 5.49% ± 0.33% and 28.07% ± 3.21%, respectively whereas after modification, these losses remained only 4.00% ± 0.80% and 24.07% ± 2.86%, respectively. The threshing efficiency remained above 99.31% ± 0.47%, for both years. Thus, optimization of combine harvester was able to save the visible grain damage by 60% to 83% and invisible grain damage by 6% to 16%, respectively during 2018 than the year 2017.

Parameter matching and experiment of the combined cyclone separation and cylinder sieve cleaning system for rape combine harvester

Existing rape combine harvester with a cyclone separation cleaning device has the challenge that the loss rate and the cleaning rate increase and decrease simultaneously.A cleaning process route was proposed,which involves the cyclone separation cleaning device removing light and tiny impurities,and the cylinder sieve device removing coarse and long impurities such as pod shells and short stems.A novel cleaning system combining the cyclone separation cleaning device and cylinder sieve cleaning devices was designed.The ranges of the structure and operation parameters for each component were analyzed based on kinematics and dynamic analysis.A four-factor five-level quadratic orthogonal test was carried out,in which the loss rate and cleaning rate were taken as the evaluation indexes.The velocity at the suction port,the rotation speed of the cylinder sieve,the screw pitch of the spiral blade and the diameter of the sieve hole were taken as the influencing factors.The orthogonal test results showed that the cleaning system performed best at a rotation speed of the winnower is 600 r/min,an airflow velocity at the suction port is 18.25 m/s,a rotation speed of the cylinder sieve is 87 r/min,a screw pitch of the spiral blade is 440 mm and a diameter of the sieve hole is 4.48 mm.At this time,the loss rate of the cleaning system is 3.22%,and the cleaning rate is 95.67%.Compared to the conventional cyclone separation cleaning device,the loss rate is reduced by 2.17%and the cleaning rate is increased by 1.05%.This study can provide a reference for the optimal cleaning system design for rape combine harvesters.

Influence of two-stage harvesting on the properties of cold-pressed rapeseed(Brassica napus L.)oils

Rapeseed(Brassica napus L.)harvesting method is critical since it significantly determines the seed yield,oil quality,and industrial efficiency.This study investigated the influences of harvesting methods on the quality of cold-pressed rapeseed oil of two varieties.Oil color,peroxide value(POV),tocopherol content,fatty acid composition,and polarity of total polyphenols(PTP)contents of two rapeseed varieties in Huanggang and Xiangyang were compared through artificially simulated combined harvesting and two-stage harvesting.Results showed significant differences in the quality of rapeseed oil between the two harvesting methods.The red value(R-value),POV,total tocopherol contents,linoleic and linolenic acid content,and PTP content of the pressed rapeseed oil prepared by the combined harvesting method were about 27.6,5.7,15.8,2.0,0.5,and 28.6%lower than those of the oil produced from the two-stage harvesting method,respectively.Xiangyang and Huayouza62 performed better in the two regions and two varieties,respectively.To sum up,the rapeseed oil obtained 41–44 days after final flowering of combined harvesting,35 days after final flowering,and six days of post-ripening of the two-stage harvesting had the best quality.

Experiment and parameter optimization of an automatic row following system for the traction beet combine harvester

To improve the automation level and operation quality of China's beet harvester and reduce the loss due to damaged and missed excavation,this study used a self-developed sugar beet combine harvester and field simulation experiment platform,based on the single-factor bench test of the automatic row following system in the early stage,taking hydraulic flow A,spring preload B,and forward speed C which have significant influence on performance indices as test factors,and taking the missed excavation rate,breakage rate and reaction time as performance indices,the orthogonal experimental study on the parameter optimization of the three-factor and three-level automatic row following system with the first-order interaction of various factors was carried out.The results of the orthogonal experiments were analyzed using range analysis and variance analysis.The results showed that there were differences in the influence degree,factor priority order and first-order interaction,and the optimal parameter combination on each performance index.A weighted comprehensive scoring method was used to optimize and analyze each index.The optimal parameter combination of the overall operating performance of the automatic row following system was A 2B 2C 1,that is,the hydraulic flow was 25 L/min,the forward speed was 0.8 m/s,and the spring preload was 198 N.Under this combination,the response time was 0.496 s,the missed excavation rate was 2.35%,the breakage rate was 3.65%,and the operation quality was relatively good,which can meet the harvest requirements.The comprehensive optimization results were verified by field experiments with different ridge shapes and different planting patterns.The results showed that the mean values of the missed excavation rate of different planting patterns of conventional straight ridges and extremely large"S"ridges were 2.23%and 2.69%,respectively,and the maximum values were 2.39%and 2.98%,respectively;the average damage rates were 3.38%and 4.14%,and the maximum values were 3.58%and 4.48%,which meet the industry standards of sugar beet harvester operation quality.The overall adaptability of the automatic row following system is good.This study can provide a reference for research on automatic row following harvesting systems of sugar beets and other subsoil crop harvesters.

Effects of working parameters on the performance of cyclone separator for rapeseed combine harvester based on CFD

Existing development for cyclone separation cleaning components of the rapeseed combine harvester,which employs the suspending airflow to separate the rapeseeds from the materials other than grain(MOG),has the challenge to figure out the optimal working parameters,highlighting a need for exploration of the invisible airflow based on Computational Fluid Dynamics(CFD).The airflow status was mainly affected by the air velocities of the inlet,and the outlet for the MOG.The single factor and response surface experiments were carried out.It could be found that the inlet and MOG outlet velocities affected the air velocities through the change in the air quantity.Furthermore,the mathematical model of the relationship between the air velocities inside the cyclone and the working parameters was built,and the optimal combination of working parameters was obtained by multi-objective optimization.The inlet and outlet velocities of the optimal combination were 4.25 m/s and 29.87 m/s,respectively.Under this condition,the cleaning ratio and loss ratio of the cleaning device was 94.62%and 5.39%,respectively,as validated by the field experiment.The findings provide references for the improvement of cleaning systems for rapeseed combine harvesters.

Artificial neural network-based repair and maintenance cost estimation model for rice combine harvesters

This research proposes an artificial neural network(ANN)-based repair and maintenance(R&M)cost estimation model for agricultural machinery.The proposed ANN model can achieve high estimation accuracy with small data requirement.In the study,the proposed ANN model is implemented to estimate the R&M costs using a sample of locally-made rice combine harvesters.The model inputs are geographical regions,harvest area,and curve fitting coefficients related to historical cost data;and the ANN output is the estimated R&M cost.Multilayer feed-forward is adopted as the processing algorithm and Levenberg-Marquardt backpropagation learning as the training algorithm.The R&M costs are estimated using the ANN-based model,and results are compared with those of conventional mathematical estimation model.The results reveal that the percentage error between the conventional and ANN-based estimation models is below 1%,indicating the proposed ANN model’s high predictive accuracy.The proposed ANN-based model is useful for setting the service rates of agricultural machinery,given the significance of R&M cost in profitability.The novelty of this research lies in the use of curve-fitting coefficients in the ANN-based estimation model to improve estimation accuracy.Besides,the proposed ANN model could be further developed into web-based applications using a programming language to enable ease of use and greater user accessibility.Moreover,with minor modifications,the ANN estimation model is also applicable to other geographical areas and tractors or combine harvesters of different countries of origin.

Research and optimization of the hand-over lifting mechanism of a sweet potato combine harvester based on EDEM

In order to meet the challenge of high loss rate and high tuber injury rate during the operation of the 4UZL-1 sweet potato combine harvester,the sweet potato tuber hand-over lifting mechanism was designed based on a comprehensive analysis of the entire structure of the harvester.Taking the average normal force on conveying sweet potato tubers as evaluation indexes,the EDEM simulation experiment was carried out considering the factors of the angle of the excavating and conveying mechanism,the conveying angle of the scraper chain,the speed of the excavating and conveying mechanism,and the speed of the scraper chain conveying.The experimental findings indicated that the optimal operational performance of the hand-over lifting mechanism was achieved at a speed of 1.15 m/s for the excavating and conveying mechanism,an angle of 24°for the excavating and conveying mechanism,a conveying speed of 0.66 m/s for the scraper chain,and a conveying angle of 60°for the scraper chain.Field experiments were conducted based on the EDEM simulation experiment,using the loss rate and the injury rate of conveying sweet potato tubers as evaluation indexes.The results showed that the hand-over lifting mechanism demonstrated optimal operational effectiveness with an excavating and conveying mechanism angle of 20°,a scraper chain angle of 68°,an excavating and conveying mechanism speed of 1.2 m/s,and a scraper chain speed of 0.66 m/s,while the machine running speed was maintained at 1 m/s.At the moment,the hand-over lifting structure exhibited a loss rate of 1.12%and a tuber injury rate of 0.94%.The conclusions obtained serve as a valuable reference for future research and optimization of sweet potato combines.

基于PLC技术的联合收割机电气控制系统设计

以联合收割机电气控制系统为研究对象,利用可编程控制器(PLC)对联合收割机电气控制系统进行改进,以提高联合收割机运行效率和可靠性。通过对联合收割机的工作原理和液压作动系统进行分析,基于可编程控制器(PLC)进行联合收割机电气系统整体设计,并对电气系统的运行效果进行测试分析。试验结果表明:系统运行可靠,能够获得良好的收割效果,可将收割损失率控制在2%以内,验证了系统运行过程稳定性。

基于立体视觉下联合收获机边缘检测技术的研究

智能联合收割机是目前作物收获的发展热点与研究重点技术之一,而确定田间地块边缘、未收割作物边缘、联合收获机直线行驶和在作物地头转向是实现全田间自动收获的基础。为此,设计了一种基于立体视觉下多种作物收获边缘快速检测方法,保持作物收获边缘在检测目标区域内,并提出了一种基于HSV(色调、饱和度和值)空间扫描的动态感兴趣区域提取算法,利用Ostu算法获得作物未收获面积,实现未收获作物边缘和作物末端边缘的同时检测,并根据作物收获末端边缘自动转向到下一个收割路径。田间验证试验表明:水稻检测准确率高于98%,玉米的检测准确率高于94%,平均处理速度为49frame/ms。研究结果表明:提出的基于立体视觉下联合收获机边缘检测及精准转向系统具有较高的工作精度和效率,可为提高作物收获性能提供技术参考与借鉴。

基于ProE的联合收割机二级齿轮减速器仿真分析

针对联合收割机二级齿轮减速器总体结构进行了设计,基于Pro/E建立了二级齿轮减速器模型并完成了产品的装配,最后利用Pro/E Mechanism仿真模块对所设计产品进行了运动仿真。结果表明:模型满足设计需求,具有较好的稳定性,对二级齿轮减速器进一步的优化设计具有一定参考作用。

联合收割机裂纹转子与滚动轴承故障诊断系统研究--基于卷积神经网络

首先,介绍了传统神经网络,在其基础上引出了改进的卷积神经网络;然后,搭建了转子和滚动轴承的动力学模型,对转子和轴承的裂纹模型进行分析研究;最后,实现了联合收割机裂纹转子与滚动轴承故障诊断系统。实验结果表明:基于卷积神经网络的诊断模型达到稳定识别精度的迭代次数更少,且识别精度更高,效果更好,证明了系统的可行性和可靠性。

联合收割机滚动轴承故障诊断系统研究--基于声场空间分布特征

首先,介绍了联合收割机滚动轴承振动机理和故障特征,并研究了基于声场空间分布特征的故障诊断流程;然后,对联合收割机滚动轴承的声音信号采集及特征提取进行了深入研究;最后,利用神经网络算法的模式识别对联合收割机滚动轴承的故障进行诊断。验证结果表明:系统对联合收割机滚动轴承故障的综合诊断率为91.67%,系统具有可行性。

内蒙古半干旱冷凉地区燕麦与箭筈豌豆混播生产性能及营养价值评价

为筛选出适宜内蒙古半干旱冷凉地区燕麦(Avena sativa)与箭筈豌豆(Vicia sativa)最佳混播组合、比例和刈割期,本研究以燕麦‘蒙饲燕1号’(‘Mengsiyan 1’)、‘蒙饲燕2号’(‘Mengsiyan 2’)、‘青引1号’(‘Qing yin1’)分别和箭筈豌豆混播为研究对象,对不同混播组合和比例的饲草在不同刈割期生产性能、营养品质及土壤养分等指标进行测定分析与综合评价。结果表明:1)不同混播能够显著提高箭筈豌豆的株高、鲜重和干重(P <0.05);以燕麦150 kg·hm^(−2)和箭筈豌豆75 kg·hm^(−2)单播量配比的‘蒙饲燕1号’+箭筈豌豆混播(3:1)在乳熟期、‘蒙饲燕2号’+箭筈豌豆混播(1:1)在乳熟末期干草产量最高;‘青引1号’+箭筈豌豆混播在各刈割期干草产量均低于同期燕麦单播产量。2)不同混播处理粗蛋白含量较燕麦单播基本呈增加趋势,粗蛋白含量从抽穗期、乳熟期到乳熟末期逐渐降低;水溶性碳水化合物(WSC)含量均在乳熟末期达到最高;不同混播组合在1:3的比例下酸性洗涤纤维(ADF)和中性洗涤纤维(NDF)含量均最低。3)燕麦与箭筈豌豆混播能够显著提高土壤有机质和速效氮含量。通过隶属函数法对混播饲草产量与营养品质进行综合评价,各混播组合中‘蒙饲燕1号’+箭筈豌豆混播(1:3)、‘蒙饲燕2号’+箭筈豌豆混播(1:1)和‘青引1号’+箭筈豌豆混播(1:3)分别在乳熟末期刈割隶属综合评价值较高,其中‘蒙饲燕1号’+箭筈豌豆混播(1:3)最佳(0.70)。

玉米联合收获机清选控制系统设计与试验

玉米联合收获机清选系统工况复杂,存在收获质量差、效率不高等问题。基于此,设计一套清选损失率控制为主同时兼顾含杂率的自动控制系统。首先分析以风机转速、振动筛转速和喂入量为影响因素,损失率、含杂率为评价指标的正交试验数据,获取影响损失率和含杂率的主次因素,提出清选系统自动控制策略;其次,为开展控制策略和算法的研究,建立清选系统中的风机转速、振动筛转速调节装置以及收获机纵向运动的数学模型,设计离散化PID控制算法。最后,基于MATLAB/dSPACE软硬件环境,搭建清选控制系统的硬件在环仿真平台,并进行控制器在环测试。试验证明:本文设定的双目标联合控制策略和控制算法,能够有效降低清选损失率、含杂率,其中清选损失率降到2.7%左右,含杂率为2.8%左右。

联合收获机发动机风冷系统优化设计

为了减少联合收获机收获过程中水箱“开锅”现象的发生,延长收获机的无故障工作时长,对4LXZ-8F型联合收获机的发动机风冷系统散热量进行了计算,并基于计算结果对防尘罩、散热器进行了优化设计,对冷却风扇进行了匹配选型。利用SolidWorks对优化前后风冷系统进行了三维建模,利用Fluent软件对发动机风冷系统优化前和优化后散热器散热性能分别进行仿真分析。仿真结果表明:优化前的冷却水入口温度为90℃,出口温度为72.3℃,进出口温差为17.7℃;优化后的冷却水入口温度为90℃,出口温度为71.1℃,进出口温差为18.9℃,表明优化后散热器散热性能提升了6.78%。研究成果可为提高发动机风冷系统的散热性能,延长无故障收获时长提供理论指导。

4BL-1型白萝卜联合收获机缨叶聚拢装置优化与试验

为解决白萝卜机收过程中因缨叶聚拢不全导致损失率与损伤率高、切头合格率低等问题,该研究依据白萝卜缨叶物理力学特性,设计了一种白萝卜缨叶聚拢装置,以实现白萝卜缨叶从田间自然“半散开”状态聚拢成束,利于后续拔取作业。构建白萝卜缨叶聚拢装置运动学模型,确定“拢缨速比”的取值范围;构建装置结构参数和前进速度、拢缨速比及作业姿态等运动参数及拢叶机构倾角对缨叶聚拢性能影响的数学模型,并求解出各因素优选区间。以缨叶聚拢成功率、缨叶破损率为评价指标,开展三因素三水平正交组合试验,依据响应面法分析各因素对二者的影响效应,并对模型进行优化。试验结果表明:缨叶聚拢成功率影响显著性顺序为前进速度、拢缨速比、拢叶机构倾角;缨叶破损率影响显著性顺序为拢缨速比、拢叶机构倾角、前进速度;最优参数组合为:前进速度0.4 m/s、拢缨速比3.9、拢叶机构倾角86.3°。在最优参数组合下开展台架试验验证,结果表明:缨叶聚拢成功率、缨叶破损率分别为92.04%、8.81%,满足拔取式白萝卜联合收获机缨叶聚拢需求。研究结果可为白萝卜收获机械的设计提供参考。

花生半喂入联合收获二次清选机构研究

针对目前半喂入花生联合收获机其清选环节存在清选损失率高、荚果含杂率高等问题,基于花生一次清选后花生荚果破损机理,设计一种二次清选装置,主要包括输送链、栅条筛、筛架、液压缸、滑土板,并确定该装置的基本参数。通过ADAMS软件分析,建立清选过程中花生与装置碰撞模型,确定以筛子转速、筛子安装高度、筛子倾角为主要影响因素,并针对“宇花14号”花生品种进行试验研究。结果表明:筛子安装高度为29 cm、筛子转速为147 r/min、筛子安装角度为19°,对应的荚果含杂率为1.65%、清选损失率为1.37%。试验结果表明,应用该装置的两垄四行花生联合机作业效果明显提高。

基于联合收获机平台的覆秸式油菜联合播种机研制

针对长江中下游稻油轮作区水稻收获后留茬高、传统旋耕装置秸秆还田能力不足导致油菜成苗率不高等问题,该研究设计了一种基于联合收获机平台的覆秸式油菜联合播种机。为提高机具通过性,结合曲柄滑块机构运动原理,根据运动学分析对悬挂装置结构进行改进,增大后悬挂装置离地间隙;为实现秸秆覆盖还田,基于联合收获机脱粒装置结构特点增设秸秆粉碎侧抛装置,对秸秆粉碎和抛送过程开展动力学和运动学分析,确定了秸秆粉碎和铺放质量的影响因素。以机具前进速度、发动机动力输出转速为试验因素,以碎土率、厢面平整度、秸秆粉碎合格率和秸秆铺放均匀性为试验指标,开展单因素试验与二因素三水平中心复合试验,得到各因素对试验指标的影响规律及响应面模型。试验结果表明,前进速度和发动机动力输出转速对种床质量及秸秆粉碎铺放效果均影响显著(P<0.05),在前进速度2.89 km/h、发动机动力输出转速2210 r/min时碎土率为85.65%,厢面平整度为20.06 mm,秸秆粉碎合格率为90.31%,秸秆铺放均匀性为89.33%,机具作业效果较优。对优化后的作业参数进行圆整并开展验证试验,结果表明,在前进速度3 km/h、发动机动力输出转速2200 r/min时,碎土率为85.69%,厢面平整度为21.32 mm,秸秆粉碎合格率为89.35%,秸秆铺放均匀性为88.07%,与理论值的偏差分别为0.04个百分点、1.26 mm、0.96和1.26个百分点。研究结果可为油菜机械化播种和一机多用提供新思路。