Increasing the appropriate seedling density for higher yield in dry direct-seeded rice sown by a multifunctional seeder after wheatstraw return

Dry direct-seeded rice(DDR) sown using a multifunctional seeder that performs synchronous rotary tillage and sowing has received increased attention because it is highly efficient,relatively cheap,and environmentally friendly.However,this method of rice production may produce lower yields in a rice–wheat rotation system because of its poor seedling establishment.To address this problem,we performed field experiments to determine the rice yield at five seedling density levels(B1,B2,B3,B4,and B5=100,190,280,370,and 460 seedlings m-2,respectively) and clarify the physiological basis of yield formation.We selected a representative high-quality rice variety and a multifunctional seeder that used in a typical rice–wheat rotation area in 2016 and 2018.The proportion of main stem panicle increased with increasing seedling density.There was a parabolic relationship between yield and seedling density,and the maximum yield(9.34-9.47 t ha-1) was obtained under B3.The maximum yield was associated with a higher total spikelet number m-2 and greater biomass accumulation from heading to maturity.The higher total spikelet number m-2 under B3 was attributed to an increase in panicle number m-2 compared with B1 and B2.Although the panicle numbers also increased under B4 and B5,these increases were insufficient to compensate for the reduced spikelet numbers per panicle.Lower biomass,smaller leaf area,and lower N uptake per plant from the stem elongation stage to the heading stage were partially responsible for the smaller panicle size at higher seedling density levels such as B5.The higher biomass accumulation under B3 was ascribed to the increases in the photosynthetic rate of the top three leaves m-2 of land,crop growth rate,net assimilation rate,and leaf area index.Furthermore,the B3 rice population was marked by a higher grain–leaf ratio,as well as a lower export ratio and transport ratio of biomass per stem-sheath.A quadratic function predicted that 260-290 seedlings m-2 is the optimum seedling density for achieving maximum yield.Together,these results suggested that appropriately increasing the seedling density,and thereby increasing the proportion of panicles formed by the main stem,is an effective approach for obtaining a higher yield in DDR sown using a multifunctional seeder in a rice–wheat rotation system.

Seed Zone Properties and Crop Performance as Affected by Three No-Till Seeders for Permanent Raised Beds in Arid Northwest China

The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds （PRB） systems. This is particularly important in arid Northwest China where large volumes of residue are retained on the soil surface after harvest. In Zhangye, Gansu Province, China, a field trial assessed the effects of three typical （powered-chopper, powered-cutter and powered-disc） PRB no-till seeders and one traditional seeder on soil disturbance, residue cover index, bulk density, fuel consumption, plant growth, and subsequent yield. In general, seedbed conditions and crop performance for PRB no- till seeders seeded plots were better than for traditional seeded plots. In PRB cropping system, the powered-chopper seeder decreased mean soil disturbance and increased residue cover index compared to powered-disc and -cutter seeders. However, the results indicated that soil bulk density was 2.3-4.8% higher, soil temperature was 0.2-0.6℃ lower, and spring wheat emergence was 3.2-4.7% less. This was attributed to greater levels of residue cover and firmer seedbeds. Spring maize and wheat performance in the powered-cutter and -disc treatments was better （non-significant） than powered- chopper treatment. So powered disc no-till seeder, which generally provided the best planting condition and the highest yield, appeared to be the suitable seeder in heavy residue cover conditions. Considering the precision requirements for soil disturbance and residue cover, the powered strip-chopping no-till seeder could be a suitable option for PRB cropping system in Northwest China. Although these results are preliminary, they are still valuable for the design and selection of no-till seeders for PRB cropping systems in arid Northwest China.

Research on Virtual Simulation of Seeder

In this study, the modeling and simulating of seeder were researched, and the method of virtual designing of seeder using computer was implemented. Based on these, general method of seeder virtual simulation was implemented using eon studio. The virtual designing, operation showing of farm machinery can be operated on website.

Supporting Seeder and Planting Technology for Spring Corn in Arid Areas

The annual rainfall is low and the fresh water resources are scarce for the rainfed farming in dry zone of northern China,which seriously affects the sowing and growth of spring corn. In order to solve this problem,the technology of ridge-mulching and side-sowing of spring corn is put forward,the supporting compound operation seeder is developed,and the effect of different speed on the quality of sowing is tested and analyzed. Under the test conditions described in this paper,the seeding operation with a high speed( up to 6 km/h) can be realized,and the quality of the seeding operation can meet the requirements of the national standards. The application of this machine can solve the problem of " drought damage at the booting stage" for spring corn,thereby realizing the deep fusion of farming machine and agronomy in dry farming of northern China,and achieving the integration of farming machine and agronomy.

Lowland manual seeder

The transplanter for root-washing and soil-bear-ing seedlings has not been perfect in South China,especially in muhicrop regions,The reason for thisis mainly because the farmers have difficulty onoperating and maintaining the machine for its com-plex design.One of the recent interests in rice culti-

俯仰式播种单体仿形性能检测试验台设计与试验

为解决播种单体仿形机构性能难以检测的问题,设计了俯仰式播种单体仿形性能检测试验台。阐述了试验台组成结构与工作原理,对其高速传动系统、液压升降系统、监控系统以及关键部件参数进行设计。应用ANSYS软件对台架整体和关键部件进行静力学分析和模态分析,验证结构设计的合理性。为检验俯仰式播种单体仿形性能检测试验台的实际检测效果,以德邦大为1205型牵引式免耕精量播种机播种单体为研究对象,先以液压杆伸出量与传送带速度为试验因素,以监控系统误差为评价指标进行试验。试验得出,在液压杆伸出量为0~200 mm范围内,监控系统角度传感器最大误差为0.69 mm;在传送带速度8~19 km/范围内,光电编码器最大误差为0.18 km/h。确认监控系统准确性后,再以单体速度为试验因素,采集速度8、10、12 km/h下地块的起伏数据为目标曲线,以地形起伏模拟曲线的绝对误差平均值为指标进行单因素试验,试验得出,所设计的试验台可有效模拟田间地面的起伏频率与起伏量,绝对误差平均值为1.86 mm,满足播种单体仿形性能检测需求。

育种播种机钢索复卷测程装置的结构设计与试验

目前,小区育种播种机定长获取方式主要通过人工测量,效率低且作业强度大,严重制约了小区育种机械的快速发展。为此,设计了一种钢索复卷测程装置,采用自动收放式测程,通过探测装置检测钢索固定的钢制或橡胶等材质球体获取小区育种播种机区间位置数据信号。为了确定不同前进速度下钢索复卷测程装置连续工作的合理参数范围,通过样机试验对装置进行参数优化。试验结果表明:往复导线轮V型角度在10°~20°之间,往复丝杠长度在400~450mm之间,装置运行稳定且无钢索缠绕和收排线集中等问题,带有触点式的行程开关的信号传输和控制运行稳定可靠,达到了育种播种机测程的要求。

多重扰动清种式大蒜单粒取种排种器设计与试验

针对勺链式大蒜播种机取种过程中常出现的漏种、重种问题,设计了一种多重扰动清种式大蒜单粒取种排种器。取种勺在充种阶段获取多粒蒜种,经多重扰动清种,最终取种勺内仅余1粒蒜种。本文以金乡蒜种为研究对象,阐述了排种器的工作原理,确定了排种器的各项参数和多重扰动装置的最佳安装位置。通过DEM-MBD耦合仿真试验,分析了倾斜角、取种勺线速度对充种成功率的影响,以及凹槽形状对单粒取种率的影响。运用Box-Behnken中心组合试验方法,以第2弧形突出部分坡度、倾斜角、取种勺线速度为试验因素,以单粒取种率和漏种率作为评价指标,开展了三因素三水平正交试验。利用Design-Expert 8.0.6数据分析软件,分析了各因素对单粒取种率与漏种率的影响,对试验因素进行优化,确定了多重扰动装置最佳结构参数。设计试验台对仿真结果进行验证,倾斜角、取种勺线速度分别为15°、0.07 m/s的条件下,通过调节多重扰动装置与取种勺凹槽顶端距离适配不同级别蒜种,当Ⅰ级、Ⅱ级、Ⅲ级蒜种距离分别为0、6.1、12.1 mm时,单粒取种成功率分别为92.2%、97.2%、95.6%,具有良好的取种性能。

玉米免耕播种机振动特性及对排种器排种性能的影响

为研究玉米免耕播种机振动特性以及振动对排种器漏播指数和重播指数的影响,搭建一套由振动加速度传感器、电荷放大器、USB采集卡组成的播种作业振动测试系统,在玉米免耕播种机免耕地表作业时进行振动测试采集播种作业的振动信号。因田间工作环境复杂,使用经典滤波法中的IIR滤波器滤除所采集振动信号中其他高频干扰信号,对田间采集振动信号进行时域分析,均方值作为时域分析指标值。结果表明:振动加速度均方根随着作业速度和旋耕机转速的增加呈线性增加,旋耕机转速和作业速度是引起玉米免耕播种机振动的主要因素,影响顺序为:旋耕机转速>作业速度。使用二次积分法对田间采集信号进行分析,得出播种机作业时最大振动位移为16.004mm,对振动信号进行频域分析,使用直接法求出功率谱密度。结果表明:玉米免耕播种机振动频率主要在0~100Hz之间,频率分布与旋耕机转速影响较大。根据田间振动信号所得工作参数搭建振动试验台,以播种机振动频率、振动幅值、作业速度为试验因素,合格指数、漏播指数为评价指标进行3因素3水平响应面试验。结果表明:作业速度、振动幅值和振动频率对合格指数和漏播指数影响较为显著。各因素对合格指数影响顺序为:振动幅值、作业速度、振动频率;各因素对漏播指数影响顺序为:振动幅值、振动频率、作业速度。研究结果可为降低玉米免耕播种机振动和优化指夹式排种器提供理论参考。

基于预知维修的小麦播种机运行监控系统设计

为了减少播种机故障频率,提升小麦播种机的播种效率和播种质量,基于预知维修对小麦播种机的运行监控系统进行了设计。系统的主要组成包括主控单片机、检测系统、显示监控系统、报警系统及电源。为了对播种机进行预知维修,将灰色模型和神经网络模型结合,建立了动态灰色神经网络模型,并进行了算法设计。为了验证小麦播种机监控系统性能和预知维修算法的有效性,对其进行了监测精度和趋势预测试验,结果表明:监测系统的监测精度较高,播种机可有效对数据趋势进行预测。

基于机器深度学习的小麦播种机控制系统研究

针对我国小麦播种机自动控制系统的可靠性及灵敏度不高的问题,基于机器深度学习对小麦播种机的控制系统进行了设计和改进。小麦播种机的主要组成包括控制系统、排种系统、监控系统、电力系统、机架和驾驶室、覆土镇压和排肥装置。为了使播种机的控制系统能有效进行图像检测识别,提升播种机的控制精度,采用机器深度学习中的卷积神经网络算法对控制系统进行设计,并采用迁移学习的方式对模型进行训练和检测。为了验证播种机控制系统的性能,对其进行播种精度控制和播种性能测试试验,结果表明:播种机的精度和性能均符合播种机的设计要求。

基于智能逆变技术的玉米精播机性能优化

为进一步提升我国玉米精播机的综合作业效率,以性能优化提升作为研究目标,基于智能逆变技术的深度应用展开分析。以电控逆变处理与调速机制相融合为出发点,建立正确的电控模块逆变应用数学模型,通过控制分析与硬件优化,进行整机作业试验。结果表明:基于智能逆变技术应用的玉米精播机性能优化效果明显,排种精准率与播深合格率分别可提升至94.46%与94.05%,满足精量播种机的设计要求;同时,种子的重播率与漏播率可降低至3.83%与3.06%,整机作业运行稳定,各零部件指令执行协同性好,综合效率相对提升了5.88%,充分体现了智能逆变应用的准确性与适应性,可为类似农机播种装备优化提供参考。

3D建模在播种机产品设计上三维艺术仿真

以SolidWorks2015仿真软件设计播种机为例,通过引入三维艺术,完成了播种机零部件结构的设计,并通过修改零部件特征完成了播种机3D模型和整机装配。经过SolidWorks 3D虚拟建模和装配,得出了如下结论:利用Solidworks2015对播种机进行3D建模和装配,符合播种机实际生产制造流程。

先进制造技术对播种机零部件生产的经济模型分析

首先,介绍了先进制造技术理论知识,分析了播种机整体结构及生产工艺;然后,阐述了BP神经网络分析播种机零部件生产的经济模型的依据,并搭建和实现了BP神经网络成本估算模型;最后,进行了生产验证。验证结果表明:基于BP神经网络对播种机零部件估算比较准确,采用先进制造技术生产的自动排种部件成本较普通制造设计下降12%,证实了系统的正确性和可靠性。

一型手推式玉米小区播种机研制与试验

由于我国育种单位众多且较分散,考虑投入产出比等经济效益指标影响,面临着小区试验面积小、分布不均等问题。针对玉米小区试验播种用工多、出苗差等问题,研制一种简单实用的手推式玉米小区试验播种机。对比国内外研发推广的小区播种机,该机械对操作人员技术要求不高,操作更简单;对播种地块、种子排列没有严格要求,实用性更强。非常切合我国玉米育种现状,具有很好的应用前景。

小区播种机种盒分种装置设计

针对目前小区播种机种盒分种自动化程度不高、效率较低且分种精度不高的情况,以及采购自动数粒分装机价格高昂等问题,设计了一种小区播种机种盒分种装置。该装置主要由锥形漏斗、分种导管、电动推杆、旋转提升手柄、锥体分种器、提升机构、种盒、分种盒等组成,通过更换不同分种盒实现相邻及间隔行种子的均匀投放,利用分种盒底端横向及纵向滑槽实现种盒个性化分种。以玉米、大豆和小麦种粒为原材料进行试验,结果表明,该机分种装置可有效替代人工,提升小区播种机分种作业效率和分种质量。

基于IWHO-EKF的高速免耕播种机播种深度监测系统研究

为解决免耕播种机高速(12~16 km/h)作业时因地势起伏造成机械振动与传感器测量误差导致的播种深度监测系统精度降低,以及单一传感器监测可靠性较差的问题,研究了一种基于改进野马算法(Improved wild horse optimizer,IWHO)优化扩展卡尔曼滤波器(Extended Kalman filter,EKF)中关键参数Q_(sigma)、R_(sigma1)、R_(sigma2)、R_(sigma3)的多传感器数据融合算法(IWHO-EKF)的高速免耕播种机播种深度监测系统。首先,建立以激光、超声波与角度传感器为多传感器监测单元的播种深度监测模型;其次,通过卡尔曼滤波算法对3个单一传感器分别滤波;最后,提出一种加入莱维飞行与高斯变异的IWHO-EKF算法,将滤波后的3个单一传感器进行数据融合,从而解决机械振动干扰与传感器测量误差降低的问题,同时充分发挥多传感器融合信息,确保免耕播种机高速作业时实现高精度、高可靠性播种深度实时监测。为验证其优越性,通过IWHO-EKF算法与单一传感器监测、单一传感器滤波和WHO-EKF算法进行仿真对比试验与田间试验。仿真试验表明:基于IWHO-EKF的高速免耕播种机播种深度监测算法平均绝对误差为0.073 cm,均方根误差为0.090 cm,相关系数为0.983,实现了高精度监测,且精度相较于传感器原始监测值、滤波值与WHO-EKF算法均显著提升。田间试验结果表明:基于IWHO-EKF算法的高速免耕播种机播种深度监测系统相较于3个单一传感器监测值,平均绝对误差和平均均方根误差分别降低0.063 cm和0.067 cm,同时平均相关系数提升0.027,该系统能够提高播种深度监测系统的精确性和可靠性。

小麦机械化匀播控制系统设计与试验

针对播种作业均匀性差的问题,设计基于STM32单片机的小麦机械化匀播控制系统,通过轮式机器人变速作业,并依据轮式行驶机器人实时行驶速度,控制排种电机转速,实现变速匀播。采用多级控制直流电机转速,一级控制参数为轮式行驶机器人实时行驶速度信号,采用PID控制;二级控制参数为排种器电机实时电流和转速,采用模糊PID控制。控制算法仿真结果表明,该控制算法响应时间短,超调量小,控制效果良好。播种试验结果表明,轮式行驶机器人恒速状态下的播量控制精度达96.8%,变速状态下的播量控制精度达95.1%。

遥控水稻直播机电动底盘结构设计与试验研究

针对西南丘陵山区地形要求,为提高水稻机械化种植效率与直播机具的工作稳定性,设计了一款轮式遥控水稻直播机电动底盘。对遥控水稻直播机电动底盘结构和工作原理进行了阐述,对动力系统、链传动张紧装置、播种悬挂升降装置进行设计,并分析整机在不同转弯方式下的转弯半径与爬坡和越梗时受力情况,建立坡道极限倾翻角与最大越梗高度的数学表达式。最后,对整机进行了田间试验,结果表明:水田环境下遥控水稻直播机直线行驶平均偏移率为1.26%,滑移率为1.04%,水田下陷量总体处于121~163mm之间,可成功通过坡度角为25°的田间坡道,具备较好的直线行驶能力和防滑能力,以及田埂与坡道通过性和较小的土壤破坏性,能够满足丘陵山区水稻直播对底盘的技术要求。