旋转式水稻钵苗移栽机构移栽臂设计与试验

旋转式水稻钵苗移栽机构移栽臂是移栽作业的执行部件,控制取秧和推秧动作,直接影响移栽机构取秧和推秧的成功率。针对原水稻钵苗移栽机构存在取秧时间长、成功率偏低,无推秧装置、推秧效果差等主要问题,对其移栽臂结构进行改进设计,优化凸轮机构,减小凸轮推程运动角,增加推秧装置。建立机构虚拟样机,研制机构物理样机,开展机构虚拟运动仿真和高速摄像运动试验。比较虚拟仿真和高速摄像试验移栽机构夹取秧苗时间的缩短情况,结果基本一致,表明移栽臂的改进设计是正确和合理的。开展安装不同凸轮机构和有无推秧装置的移栽机构的取秧试验,改进后的机构取秧成功率和推秧成功率分别为94.3%和98.6%,远高于改进前的82.9%和88.6%,表明改进后的机构能够更好地满足水稻钵苗移栽工作要求,且具有很好的工作性能。

Design and Test on Transplanting Arm of Rotary Transplanting Mechanism for Rice Pot-seedling

The planting arm of rotary transplanting mechanism for rice pot-seedling is the operation component which is used for seedling picking-up. The motion of seedling control and pushing will affect the success rate of seedling picking-up and seedling pushing directly. Aiming to solve the problems such as the long time of seedling picking-up, low success rate, no pushing device and poor pushing seedlings of the original pot-seedling transplanting mechanism, the transplanting mechanism was redesigned. The main work is to redesign cam mechanism in transplanting arms using optimization design method, decrease cam-drive angle and add the seedling pushing device. With the development of virtual prototype and physical prototype, the virtual kinematics simulation and the kinematics test with high-speed digital video camera and image processing technology were carried out. The basic consistency of the shortening time in two test was demonstrated which showed the feasibility and availability of the developed design of planting arms. The seedling picking-up tests of transplanting mechanism with different cam mechanisms as well as the transplanting mechanisms with and without seedling pushing device were developed. The success rate of seedling picking-up and seedling pushing of the developed mechanism were 94.3% and 98.6%, which were 82.9% and 88.6% higher than those of the product by original pot-seedling transplanting mechanism, respectively. It was proved that the improved mechanism can meet the requirements of rice pot-seedling transplanting.