油菜移栽组合式不完全非圆齿轮行星轮系取苗机构的工作机理和参数优化

Semi-automatic transplanter is majority machine for rape transplanting in the world with low efficiency. And there are defects on mechanism structure, efficiency, cost, or adaptation for automatic transplanters which have been developed at present. For these reasons, to develop a rotary picking seedling machinery with high efficiency for rape transplanting into the field in this fund application is proposed. One innovation mechanism with combined incomplete non-circular gears which can continuously drive is developed in this research. It would conquer the problems, including rigid contact with high impact for intermittent transmission mechanism with the locking lone, form orbit and dynamic performance unsatisfactory for two-order non-circular gears continuously transmission mechanism in the three generations’ rotary picking seedling machinery. The new mechanism has the property of two times of transmission ratio fluctuation continuously and sharply in motion period. It’s useful for the rotary picking seedling machinery to form the ideal working path. Focus on the objective of developing high speed and efficiency picking seedling machinery to do the research in this project. Study on the kinematics characteristics and design of the combined incomplete non-circular gears mechanism, modeling the rotary picking seedling machinery and parameter automatic guided optimization with fuzzy mathematics, reliability modeling of mechanism kinematics accuracy for eliminating joint clearance and dimension error, optimizing the dynamics model of mechanism, verification test by test bed, and so on. The successful project implementation will guide innovative design of rape transplanter with the automatic picking seedling function machinery. It will provide important theory and design basis for the high speed seedling transplanter in dry land, and promote the development of industrial scale for rape.

针对目前国内外油菜移栽机构半自动为主效率低，以及已研发自动移栽机构结构、效率或成本适应性等存在的缺陷，提出研发一种旋转式油菜钵苗田间高速取苗移栽机构。本项目研究基于前期三代旋转取苗机构存在带锁止孤间歇旋转机构传动刚性接触冲击大、二阶非圆齿轮连续旋转机构形成轨迹及动力性能不理想问题，进一步创新提出一种组合式不完全非圆齿轮连续传动机构；新机构具有周期内二次传动比连续大幅度波动特性，有利于旋转式取苗机构实现理想取苗和推苗工作轨迹。围绕研发高速高效取苗移栽机构目标，开展：组合式不完全非圆齿轮机构运动学特性与设计、旋转式取苗机构运动学建模与模糊数学参数自动导引优化、消除运动副间隙和尺寸误差的运动可靠性模型、机构动力学建模与优化、台架验证试验等方面研究。项目成功实施，将直接指导具有自动取苗功能的油菜钵苗移栽机构的创新设计，为旱地高速钵苗栽植机的研发提供重要理论基础和设计依据，促进油菜产业规模化发展。

针对目前国内外旱地移栽机构以半自动为主，工作效率低、栽植质量差，已研发的自动移栽机构结构复杂、成本高，且日本的机构效率不高、振动大，欧美的机构不适合国内穴盘苗移栽作业等问题，本项目将开展旱地穴盘苗自动取苗机构的工作机理、创新设计、参数优化和相关试验研究。本研究基于蔬(油)菜穴盘苗移栽农艺的规划理想机械取苗轨迹，研究出具有周期内传动比二次不等幅较大波动特性的组合式不完全非圆齿轮机构的运动学特性与设计方法。新型取苗机构可避免前期研发的旋转取苗机构存在带锁止孤间歇旋转机构传动刚性接触冲击大、二阶非圆齿轮连续旋转机构形成轨迹及动力性能不理想问题。研究了组合式不完全非圆齿轮行星轮系旋转式取苗机构的运动特性，建立取苗机构的运动学模型，采用基于参数导引的“正向设计”方法，开发该取苗机构的辅助分析与优化软件，开展取苗机构的正向设计。分析推苗段局部轨迹调整对推苗姿态的影响，为了获得更为理想的推苗段轨迹，采用基于局部轨迹的“反求设计”确定行星轮系取苗机构参数与非圆齿轮节曲线，并研究不规则非圆齿轮节曲线的表示方法。建立组合式不完全非圆齿轮行星轮系旋转式取苗机构的运动可靠性模型，开展机构的运动可靠性研究。研究了组合式不完全非圆齿轮行星轮系取苗机构的动力学建模和特性，优化机构动力学性能。开展了组合式不完全非圆齿轮行星轮系取苗机构的试验研究，测试机构运动学与动力学特性，修正理论模型，检验机构取苗作业性能。在项目实施期间共发表录用期刊论文10篇，其中8篇被SCI/EI收录；获得授权国家授权发明专利5件，软件登记5件，培养研究生9人，为我国农机生产企业培养了优秀的设计人才。通过上述研究总结出了一套组合式不完全非圆齿轮行星轮系取苗机构的设计理论与优化方法，建立的研究平台，为开发具有自主知识产权、适合我国国情、能实现产业化的旱地穴盘苗高速自动移栽机打下坚实的理论和研究基础。