农机化研究

为了解决机械化采摘香榧成熟度一致性低的问题，设计了一款变力激振式香榧手持采摘设备。针对香榧结果的农艺特性和力学特性，确定了变力激振式采摘设备的工作原理，研发了一种双轴式变力调节曲柄，通过调节偏行块径向位置以适应不同种类的香榧采摘需求，当曲柄运动产生的激振力大于果柄结合力时实现香榧果实的掉落。采用ANSYS有限元软件对采摘头机架进行静态结构和模态分析，利用Design-Expert13进行三因素三水平组合试验。根据试验结果方差分析，以成熟果实采摘率最大、不成熟果实采摘率和幼果误采率最小为参数优化目标，得到优化参数为振动半径120 mm、曲柄转速1 500 r/min、偏心块质量1 000 g,此时成熟果实采摘率、不成熟果实采摘率和幼果误采率分别为86.46%、6.37%、2.59%,研究结果可为后续香榧机械化采摘研究提供参考。

In order to solve the problem of low maturity consistency of mechanized harvesting, a variable force excitation handheld picking equipment was designed. According to the agronomic characteristics and mechanical characteristics of the results of Torreya grandis 'Merrillii' Hu, the working principle of the variable force excitation picking equipment was determined, and a biaxial variable force adjustment crank was designed, which was adapted to the picking conditions of different kinds by adjusting the radial position of the deflection block, and the drop of the fruit was realized when the excitation force generated by the crank movement was greater than the binding force of the fruit stalk. The static structure and modal analysis of the picking head frame were carried out by ANSYS finite element software, the appropriate excitation frequency and crank parameters were determined by single factor test, and the three-factor and three-level combination test was carried out by Design-Expert13. According to the analysis of variance of the experimental results, the parameter optimization was based on the maximum picking rate of ripe fruit, the minimum picking rate of immature fruit, and the minimum mispicking rate of young fruit, the optimized parameters was obtained: the vibration radius of 120 mm, the crank speed of 1,500 r/min and the eccentric mass of 1,000 g, the picking rate of ripe fruit, the picking rate of immature fruit and the mispicking rate of young fruit were 86.46%, 6.37% and 2.59%, respectively. The results could provide a reference for the subsequent mechanized harvesting of Torreya grandis ′Merrillii′ Hu.