刚柔混联的草莓采摘机械手结构设计与动力学分析

Vol. 24 No. 2Feb. 2018第24卷第2期2 0 1 8年2月、 计算机集成制造系统Computer Integrated Manufacturing SystemsDOI： 10. 13196/j. cims. 2018. 01. 014刚柔混联的草莓采摘机械手结构设计与动力学分析王家忠，张建宝,弋景刚（河北农业大学 机电丄程学院河北 保定071001）摘 要:针对英莓形状不规则.组织娇嫩容易受机械损伤难以实现高效低损的机械化采摘作业的问 題,提岀一种刚柔混联的机械手结构。为了建立柔顺伪刚体模型，将柔顺构件等效为具有欠驱动关节的多刚 体串联系统；采用影响系数法建立柔顺构件等效多刚体系统的动力学模型，对机械手柔性构件的动力学特性 进行仿真分析与样机试验研究。仿真和试验结果表明采用力反馈的刚柔混联机构具有良好的包络性、可控 性、平稳性及速度特性，适合于草菴的柔顺抓取控制，该成果可为草莓等果蔬无损采摘机械手的设计及优化 提供借鉴和参考。关键词：草莓采摘;机械手;刚柔混联;动力学分析;柔顺控制中图分类号:TH113;TP241. 3;TH122文献标识码:AStructure design and dynamic characteristic analysis for strawberry picking manipulatorWANG J iazhong« ZHANG Jianbao« YI Jinggang(College of Mechanical and Electrical Engineering, Agricultural University of Hebei. Baoding 07100L China) Abstract： Aiming at the problem that strawberry was difficult to realize mechanical picking because of high water content and delicate structure, a rigid flexible hybrid structure of manipulator was proposed for ridge culture. To build the pseudo rigid body model, the compliant component was taken as the multi-rigid body series system of under-actuated joint. The dynamic model of compliant component equivalent rigid body was constructed with influence coefficient method, and the simulation analysis and experimental research for dynamic characteristics of distributed compliant mechanism were carried out. The simulation result showed that the r.gid flexible mixed connection mechanism with force feedback had good envelope controllability, stability and speed characteristic, and was suitable for compliant picking of strawberry. The research on the separating device had important application value for design and optimization of strawberry and other fruits and vegetables.Keywords： strawberry picking； manipulator； rigid flexible hybrid structure； dynamics analysis； compliance control0引言草莓素有“水果皇后”之美誉，其甜酸适宜、芳香 宜人、营养丰富，然而由于草莓含水量高、组织娇嫩, 容易受机械损伤，导致其品质急剧下降、贮藏期缩 短;另外，草莓植株矮小（垄作草莓株高一般为20 cm30 cm）,作业环境复杂，其采摘过程中的避障和低损伤成为自动化采摘的关键环节因此，口 前草莓采摘作业仍以人工为主，难以实现机械化采 摘作业。为了实现草莓的自动化采摘，国内外学者做 了大量研究，大部分工作集中在研发草傩采摘机 器人，其重点和难点是机械手，即末端执行器的研 发LT）。目前，美国Harvest CROO公司、西班牙Vol. 24 No. 2Feb. 2018Vol. 24 No. 2Feb. 2018收稿日期：2017-05-03；修订日期：2017-08-16. Received 03 May 2017accepted 16 Aug. 2017.基金项目：国家口然基金资助项0(51305125)；河北省高等学校科学技术研究基金资助项目(YQ2013007). Foundation items：Project suppor- ted by the National Natural Science Foundation China(No. 51305125). and the 55cicr.cc & Technology Program of Hebei Higher Education Institutionst China(Na YQ2013007).