杏果实采摘执行机构的研究

发布时间：2018-03-29 08:19

本文选题：采摘执行机构　切入点：三维设计　出处：《吉林大学》2017年硕士论文

【摘要】：在农业生产过程中,果实采摘是最费时、费力的一个环节,且需要人工手动完成。加之农业生产本身对于季节和天气的要求也比较高,劳动力不足的问题也不断地被放大。多种因素降低了农业的生产效率,影响了农业的发展。杏作为一种营养丰富的果实在我国分布较广,针对上述问题,本文研究一种新型杏果实采摘执行机构,用以解决杏果实机械化采摘水平。本文对杏果实的物理特性进行了分析之后设计了针对杏果实的采摘机执行机构,进行了仿真分析,制作了样机,并利用电子技术和控制理论等相关知识,对杏果实采摘机执行机构控制系统进行了研究,主要研究内容如下:(1)设计了一种杏果实采摘机执行机构。针对杏果实表面比较柔软,易受到损伤的特点,选取尼龙材料作为采摘仿生指材料,且仿生指具有一定角度,采用了基于人手撸指的原理来完成采摘动作。对整个执行机构的电机、减速器以及轴承等零件进行了相应的选型。(2)使用WDW-20微机控制电子式万能试验机针对两个时期(55d和75d时期)的杏果实分别进行了拉伸试验和剪切试验。并用电子天平测得杏果实的质量,再通过计算得到含水率。利用SPSS软件进行相关性分析,得到相关系数,确立相关关系。再进行回归分析,得到回归方程,通过含水率、质量来推算采摘杏果实受到的拉伸力和剪切力的大小。观察杏果实断裂位置,判断杏果实的成熟程度并选择合适采摘执行机构的转速进行采摘,保证经济效益。(3)通过实验测得了采摘杏果实时需要力的大小,然后对采摘机关键部件进行了仿真分析,分析得到采摘仿生指、采摘执行机构以及机架在采摘时可能发生共振的频率,当进行整体实验时应该避免这三个频率下的转速,以保证采摘机执行机构不发生共振,达到不对其产生破坏的目的。(4)在采摘机执行机构装配完成的基础上,设计了控制系统的总体方案,选用了PC+运动控制卡的形式来完成控制系统硬件设计。(5)完成了采摘模拟实验,验证了采摘机执行机构能够顺利的完成采摘任务,并确定了在34 r/min的转速下可以在不伤及果实的前提下高效地完成果实的采摘,根据实验可以推断出当转速保持在30~40r/min时可以高效地采摘杏果实。本试验中东北杏的成熟日期为7月中旬,所以采摘时间应该在7月初,保证果实不被打坏的前提下,调整机器转速完成采摘,实现采摘效率最大化。
[Abstract]:In the process of agricultural production, picking fruit is the most time-consuming and laborious link, and it needs manual work. In addition, agricultural production itself requires higher requirements for seasons and weather. The problem of labor shortage has been magnified constantly. Many factors have reduced the productivity of agriculture and affected the development of agriculture. Apricot, as a kind of nutritious fruit, is widely distributed in our country. In this paper, a new kind of apricot fruit picking executive mechanism is studied to solve the mechanized picking level of apricot fruit. The physical characteristics of apricot fruit are analyzed in this paper, and then the executive mechanism of apricot fruit picking machine is designed, and the simulation analysis is carried out. The prototype was made and the control system of apricot fruit picking machine was studied by using electronic technology and control theory. The main research contents are as follows: (1) A kind of apricot fruit picking machine was designed. In view of the soft and vulnerable surface of apricot fruit, nylon material was selected as the biomimetic finger material, and the biomimetic index had a certain angle. Based on the principle of manual masturbation to complete the picking. For the motor of the whole actuator, Using WDW-20 microcomputer controlled electronic universal testing machine, the apricot fruits of two periods (55 d and 75 d) were tested by tensile test and shearing test, respectively. The quality of apricot fruit was measured. Then the moisture content is obtained by calculation. The correlation coefficient is obtained by SPSS software, and the correlation relationship is established. The regression equation is obtained by regression analysis, and the regression equation is obtained by the moisture content. The quality was used to calculate the tensile force and shear force of picking apricot fruit, to observe the broken position of apricot fruit, to judge the ripening degree of apricot fruit and to select the rotation speed of proper picking executive mechanism for picking. To ensure economic benefit. (3) the required force of picking apricot fruit was measured through experiments, and then the key parts of the picking machine were simulated and analyzed, and the bionic index of picking was obtained. The frequency of resonance in picking mechanism and frame should be avoided when the whole experiment is carried out in order to ensure that the actuator of picking machine does not resonate. On the basis of the assembly of the executive mechanism of the picking machine, the overall scheme of the control system is designed, and the hardware design of the control system is completed in the form of the PC motion control card. It is verified that the executive body of the picking machine can finish the picking task smoothly, and it is determined that the picking of the fruit can be accomplished efficiently without harming the fruit at the speed of 34 r/min. According to the experiment, we can infer that apricot fruit can be picked efficiently when the rotational speed is kept at 30~40r/min. The mature date of northeast apricot in this experiment is mid-July, so the picking time should be in early July to ensure that the fruit will not be damaged. Adjust the speed of the machine to complete the picking, to maximize the efficiency of picking.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S225.93

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