辣椒夹茎式行星轮系取苗机构优化设计与试验

Optimization Design and Experiment of Seedling Picking Mechanism for Clamping Stem Planetary Gear Train for Pepper

摘要:

针对目前辣椒移栽机械化不足、效率低等问题,本文设计了一种夹茎式三臂非圆齿轮行星轮系取苗机构。根据夹茎取苗农艺要求,设计了一条能够实现低速取苗、竖直投苗的夹茎取苗轨迹。通过分析取苗机构运动学模型,建立开链二杆机构近似多位姿优化综合模型与节曲线优化求解模型,开发了近似多位姿非圆齿轮行星轮系取苗机构优化设计软件,对取苗机构参数进行优化求解。建立了夹茎式三臂取苗机构三维模型,利用ADAMS软件开展虚拟样机运动学仿真,仿真轨迹、速度与理论轨迹、速度基本一致,初步验证了理论设计的正确性。对夹茎式三臂行星轮系取苗机构进行取苗试验,试验结果表明,当取苗机构转速为75 r/min时,取苗效率为225株/min,取苗成功率为96.88%,投苗成功率为98.39%,进一步验证了所述理论方法的正确性和机构的可行性。

Abstract:

Aiming at the problems of insufficient mechanization and low efficiency of pepper transplanting, a seedling picking mechanism of three-arm non-circular gear planetary gear train with clamping stem was designed. According to the agronomic requirements of picking seedlings by clamping stems, a trajectory of picking seedlings by clamping stems that can achieve low-speed picking seedlings and vertical throwing seedlings was designed. By analyzing the kinematics model of the seedling picking mechanism, the approximate multi-poses optimization comprehensive model and the pitch curve optimization solution model of the open-chain two-bar mechanism were established. The optimization design software of the seedling picking mechanism of the approximation multi-poses non-circular gear planetary gear train was developed to optimize the parameters of the seedling picking mechanism. Then, the three-dimensional model of the three-arm seedling picking mechanism was established, and the kinematics simulation of the virtual prototype was carried out by ADAMS software. The simulation trajectory and speed were basically consistent with the theoretical trajectory and speed, which preliminarily verified the correctness of the theoretical design. The seedling picking test was carried out on the seedling picking mechanism of the three-arm planetary gear train. The test results showed that when the rotation speed of the seedling pick-up mechanism was 75 r/min, the seedling picking efficiency was 225 plants/min, the seedling picking success rate was 96.88%, the seedling throwing success rate was 98.39%, which further verified the correctness of the theoretical method and feasibility of the machanism.