荔枝采摘机器人拟人指受力分析与夹持试验

阐述了采摘机器人的新型拟人夹指机构,分析了夹持的力封闭性,建立了扰动条件下的荔枝母枝夹持模型,导出了一种夹持力计算方法;用压力机对结果母枝进行了夹持试验,建立了夹持力、母枝直径等与抓举重力间的关系,给出了定量描述;用机器人在野外环境下进行动态采摘试验,验证了夹指的可靠性。结果表明:所设计夹指结构能适合不同直径母枝的稳定夹持,对母枝损伤小;所建立的回归方程有效,夹指在外力扰动情况下可以实现稳定夹持;野外环境下使用15N夹持力采摘荔枝果串,夹持成功率为100%。

Clamping Experiment on Humanoid Fingers of Litchi Harvesting Robot

Fruit branch clamping used in robot harvesting has advantages of universal use and little damage on fruit, but the clamping stability and reasonable clamping force are the bottlenecks of finger design. Firstly, the novel humanoid fingers were elaborated and the clamping force closure was analyzed. Clip-model in the condition of disturbance was developed, and a new clamping force calculation method was deduced. Secondly, the branch clamping test was operated on press machine. The relationships among clamping force, branch diameter, and maximum snatch force were built, and the quantitative description was also established. Finally, tests were performed to verify the clamp reliability by harvesting robot in the field. Results showed that the novel humanoid fingers can realize stable clamping on different sizes of branches and have little damage on them. The clamping force model was valid. The stable clamping can be achieved with disturbance. The success rate was 100% when clamping force was 15N.This will provide some theory evidences for harvesting method and universal fruit picking manipulator.