面向水田复杂多变环境下的智能株间机械除草关键技术与机构创新研究

In the light of the difficulty to distinguish and remove the irregular flexible weeds from the traditional paddy field weeding machine, it cannot meet the precision agronomic requirements of intra-row weeding, the mechanism of separation of weeds and soil and the adhesion mechanics are studied, and the mutual coupling model of weeds and soil composite system is established. Based on the biomimetic optimization theory, a study method of finger like herbicidal parts is proposed to analyze the quality, structure and shape mechanism of the bionic projectile tooth blade with weeds excision and digging. Create a type of the electric drive self walking chassis and micro bending type weeding device between teeth, and analysis of the effect of chassis to soil mechanical rolling. Optimization of weeding parts based on the reverse design method of local parameters is studied. Study an image recognition algorithm which can identify and locate weeds in real time. The adaptive control strategy for variation of heading and crop position is analyzed, and the dynamic detection method for the depth of the chassis and the depth of the parts of the chassis is proposed. An integrated trial system is used to simplify intelligent machinery weeding device of paddy field, and to form a set of fast design, analysis and optimization methods for a complete system of plant weeding machinery. The results of project can improve the theory of mechanical weeding effectively, research methods for improving complex systems in paddy fields, and have important scientific significance and application value.

针对传统水田除草机械难以区分并有效移除株间不规则柔性体杂草，无法满足中耕除草精准作业要求，围绕智能株间机械除草关键技术与机构开展科学创新研究，揭示根土互连机制及根系结构与土壤性质相关性，研究杂草-土壤机械分离机理与粘附力学机理，建立除草部件与杂草-土壤复合系统互馈耦合模型；基于仿生优化理论提出一种株间类指形除草部件研究方法，分析杂草切除掘根的仿生弹齿刃口质、构、形机理；创制电力驱动式自走微型底盘及弯折式行间除草耙齿，分析底盘对土壤机械碾压作用；基于局部参数反求设计方法提出除草部件优化思路；研究可实时识别、精准定位杂草的图像识别算法，分析因航向偏差与作物位置变化的自适应调控策略，提出底盘行走及部件入土深度动态检测方法；集成轻简化智能株间除草样机，形成一套完整系统株间除草机械设计、分析和优化方法。有效完善株间机械除草技术理论，丰富水田复杂系统研究方法，具有重要科学意义与应用价值。

科学有效地防控草害是实现稻米高产、稳产、优质生产的重要保证，水田机械除草技术可有效改善土壤物理环境，促进肥料吸收及根须发育，减少环境污染，对提高粮食生产安全及品质，水稻全面全程机械化生产及指导农民科学田间管理具有深远意义。为实现大田环境下精准除草作业，解决稻苗与杂草难以区分、叶片交叉等问题，提高除草作业质量，本项目开展相关研究工作。主要研究内容与重要结果包括：①开展水稻秧苗受力损伤机理研究，获得水稻秧苗损伤挠曲线方程、植株拔出力学模型及水稻物理特性参数。②构型曲面轮齿斜置式行间除草部件，构建了除草轮轮齿入土、扰动、出土脱附力学模型，明晰除草轮齿脱附机理，建立除草部件—水—土壤流固耦合模型，进行了虚拟仿真试验，获得最优结构参数组合。③获取基于狗獾爪趾的除草弹齿内侧曲线方程，构型了仿生株间除草部件，开发株间除草装置自动避苗控制系统，完成了装置田间运动学试验，获得了运动工作区域。④获得了实时快速识别、精准导航定位等信息图像识别处理算法，开发除草机微型底盘控制调节系统，构型水田智能除草机，进行了田间试验，除草效果良好，除草率不低于77.9%，伤苗率不高于3%，满足水田机械除草农艺要求。本项目的实施可有效完善水田株间机械除草技术理论，丰富水田复杂系统研究方法与手段，为农业水田装备研究提供有效参考，同时研制的新型水田智能除草机械可满足我国田间管理机具生产企业对其迫切需求，具有重要科学研究意义与实际应用价值。. 在执行期内，共计发表SCI/EI论文5篇；申请发明专利2项，授权发明专利1项，授权实用新型专利3项；获得软件著作权3件；出版专著1部；培养毕业博士1名，毕业硕士2名，在读硕士生1名。在项目研究基础上，针对水田株间除草作业劳动强度大、株间除草率低、易损伤秧苗等问题，提出一种射流式水田株间除草方法，截止目前本项目已超额完成了全部计划指标。