摘要
【目的】根据浆果在采摘、分拣等环节中的夹持性能需求,在机器人末端使用高刚度驱动连接和低刚度无损夹持的夹持机构,有效推进农业机器人在浆果生产领域的推广。【方法】针对典型浆果-小番茄的夹持工况,引入多层级拓扑优化理论,提出基于梯度点阵结构的变刚度柔性夹持机构设计方法,构建变刚度柔性夹持机构的优化设计模型,实现由单一材料构建的刚度梯度分布的一体化柔性夹持机构设计。【结果】采用Polyjet增材制造技术,加工获得柔性质量约45 g的夹持机构样件。对茂名‘千禧’小番茄的夹持试验发现,夹持机构样件输入端的驱动载荷为11.00~14.56 N时,小番茄的压缩率为0.90%~1.91%,机械损伤度为0。【结论】优化设计的变刚度柔性夹持机构可有效且几乎零损伤地夹持外表层较为脆弱的浆果,为浆果自动化采摘、分拣等环节中夹持装备的设计提供了可行的设计方法。
【Objective】According to the clamping performance requirements of berries in picking,sorting and other links,to apply the berry clamping mechanism simultaneously driven with high stiffness and clamped nondestructively with low stiffness at the end of the robot,and effectively promote the application of agricultural robot in the field of berry production.【Method】Taking small tomato clamping mechanism as an example,a design method of berry compliant clamping mechanism with variable stiffness was proposed based on gradient lattice structure by introducing the theory of multi-level topology optimization.And an optimization model of this method was developed,which realized the design of an integrated compliant clamping mechanism that constructed from single material and had gradient distribution of stiffness.【Result】A prototype of compliant clamping mechanism weighing about 45 g was fabricated by Polyjet additive manufacturing technology.The results of performance test of clamping Maoming‘Millennium’small tomatoes showed that when the driving load at the input end of the sample of the clamping mechanism was 11.00−14.56 N,the compression ratio of the small tomato was 0.90%−1.91%,and the mechanical damage degree was 0.【Conclusion】The optimized compliant clamping mechanism with variable stiffness can effectively grip the fragile berries nearly nondestructively,and provide a feasible method for the design of automatic clamping equipment for berry picking and sorting.
作者
王昱
陈婉琼
曾山
凡健
孙超
姚凯斌
WANG Yu;CHEN Wanqiong;ZENG Shan;FAN Jian;SUN Chao;YAO Kaibin(College of Engineering,South China Agricultural University/Key Laboratory of Key Technology on Agricultural Machine and Equipment,Ministry of Education,Guangzhou 510642,China)
出处
《华南农业大学学报》
CSCD
北大核心
2024年第2期273-279,共7页
Journal of South China Agricultural University
基金
广州市基础与应用基础研究基金(202102020870)
智慧农场技术与装备集成应用模式与数字化展示项目(粤财农[2021]170号)。
关键词
浆果
夹持
柔性夹持机构
点阵结构
变刚度
拓扑优化
Berry
Clamping
Compliant clamping mechanism
Lattice structure
Variable stiffness
Topology optimization
