带夹式甘薯裸苗移栽机的设计与仿真

发布时间：2018-01-30 09:02

本文关键词： 甘薯移栽插秧装置送苗装置控制　出处：《山东农业大学》2017年硕士论文　论文类型：学位论文

【摘要】：甘薯是一种营养丰富、用途广泛、高产稳产的农作物。中国的甘薯种植面积和总产量均位于世界前列。在甘薯生产过程中,栽插环节是用工量最大的环节之一,占到总用工的1/4以上。因此,对甘薯移栽机械的研究可以有效地推动产业的机械化水平向前发展,对整个产业的机械化具有十分重要的意义。我国的甘薯移栽机研发使用尚处初级阶段,机具也多以半自动移栽机、简易移栽器为主。结构简单,成本低,但是无法进行膜上移栽,且无法实现精确的栽植轨迹。根据这一现状,在了解国内外现有移栽机械的基础上,研制出一种带夹式甘薯裸苗移栽机,实现了甘薯的插秧作业。主要研究内容及创新之处如下:(1)确定带夹式甘薯裸苗移栽机的总体方案,移栽机的行进方式为牵引式,主要由行走系统、送苗装置、插秧装置、夹苗装置和控制系统组成。(2)提出一种四连杆式插秧机构,并设计出由不完全齿轮机构、曲柄连杆机构、齿轮齿条机构和四连杆机构组成的插秧装置。根据甘薯苗插秧作业农艺要求的插秧轨迹,以连杆机构运动的设计轨迹与理论轨迹的偏差最小建立目标函数,利用Matlab优化工具箱提供的多变量有约束非线性最优化函数fmincon计算得出四杆机构的各个参数;利用不完全齿轮机构、曲柄连杆机构和齿轮齿条机构的组合实现插秧连杆的间歇式往复摆动;从而使插秧装置实现精确轨迹的插秧作业。(3)设计一种送苗装置。主要由槽轮机构和同步带传动装置组成,实现同步带的间歇式运动配合插秧装置的间歇式摆动,为插秧装置提供秧苗。(4)开发带夹式甘薯裸苗移栽机控制系统。控制系统的作用是根据软件程序控制浇水电磁阀的开启和气缸的动作,实现浇水作业和夹苗指的夹紧与松开。通过proteus和keil的联合仿真验证了控制系统的可行性。(5)设计移栽机行走机架及传动系统。利用Solid Works软件建立各零部件的三维模型,利用Solid Works simulation对移栽机主要零部件进行有限元分析,确保移栽机作业中各部件安全可靠.(6)对插秧装置进行了正交仿真试验,根据正交试验表讨论了不同种植土壤情况下的插秧参数配置。对于土壤比较干旱、覆膜种植的情况,最优的插秧参数为插秧装置离地高度设置为80mm,移栽机前进速度为0.3m/s,移栽株距设置为250mm;对于土壤比较干旱、不覆膜种植的情况最优的插秧参数插秧装置离地高度设置为80mm,移栽机前进速度为0.2m/s,移栽株距设置为200mm。对于土壤水肥条件比较好、覆膜种植的情况最优的插秧参数为插秧装置离地高度设置为120mm,移栽机前进速度为0.4m/s,移栽株距设置为200mm。对于土壤水肥条件比较好、覆膜种植的情况最优的插秧参数插秧装置离地高度设置为120mm,移栽机前进速度为0.3m/s,移栽株距设置为300mm。
[Abstract]:Sweet potato is a kind of crops with rich nutrition, wide use, high and stable yield. The planting area and total yield of sweet potato in China are among the top in the world. In the process of sweet potato production, planting is one of the most important aspects of employment. Therefore, the research on the transplanting machinery of sweet potato can effectively promote the mechanization level of the industry. It is very important for the mechanization of the whole industry. The research and application of sweet potato transplanter in our country is still in the primary stage, and the equipment is mainly semi-automatic transplanter, simple transplanter, simple structure and low cost. But it is impossible to transplant on film, and can not achieve accurate planting track. According to this situation, on the basis of understanding the existing transplanting machinery at home and abroad, a kind of transplanting machine of sweet potato and naked seedling with clip is developed. The main research contents and innovations are as follows: 1) to determine the overall scheme of the transplanter with clamped naked sweet potato seedling. The moving mode of the transplanter is traction type, mainly by walking system. This paper presents a four-bar seedling transplanting mechanism, which is composed of seedling feeding device, seedling transplanting device, seedling clamping device and control system. The mechanism is designed by incomplete gear mechanism and crank linkage mechanism. A seedling transplanting device composed of gear rack mechanism and four-bar linkage mechanism. According to the transplanting track required by agronomic operation of sweet potato seedling transplanting, the objective function was established by the minimum deviation between the design track of linkage mechanism motion and the theoretical track. The parameters of the four-bar mechanism are calculated by using the multi-variable constrained nonlinear optimization function fmincon provided by the Matlab optimization toolbox. Using the combination of incomplete gear mechanism, crank linkage mechanism and gear rack mechanism, the intermittent reciprocating swing of seedling transplanting linkage is realized. Thus, a seedling feeding device is designed for seedling transplanting device with precise track. It is mainly composed of slot wheel mechanism and synchronous belt transmission device. The intermittent movement of the synchronous belt is combined with the intermittent swing of the seedling transplanting device. The control system of the transplanting machine is developed. The function of the control system is to control the opening of the solenoid valve and the action of the cylinder according to the software program. Through the joint simulation of proteus and keil, the feasibility of the control system is verified. The walking frame and transmission system of the transplanter are designed. The 3D model of each component is established by using Solid Works software. The finite element analysis of main parts of transplanting machine is carried out by using Solid Works simulation. In order to ensure the safety and reliability of each part of transplanting machine, the orthogonal simulation test of seedling transplanting device was carried out. According to the orthogonal test table, the allocation of transplanting parameters under different planting soil conditions was discussed, and the soil was relatively dry. In the case of film mulching planting, the optimum transplanting parameters were as follows: the height of transplanting device was 80mm, the speed of transplanting machine was 0.3 m / s, the distance of transplanting plant was 250mm; For the dry soil, the optimum transplanting parameters were set to 80 mm from the ground and the speed of transplanting machine was 0.2 m / s. The distance of transplanting plant was set to 200mm. for the condition of soil water and fertilizer, the best transplanting parameter was that the height of transplanting device was 120mm from the ground. The moving speed of transplanter is 0.4m / s, the distance of transplanting plant is 200mm. the soil water and fertilizer conditions are better. The optimum transplanting parameters of film mulching were as follows: the height of transplanting device was 120mm, the moving speed of transplanter was 0.3 m / s, and the distance of transplanting was 300mm.
【学位授予单位】：山东农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S223.9

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