柔性机械手设计与夹取力动态特性仿真分析

Design of the flexible manipulator and dynamic characteristics analysis of clamping force

设计了一种以驱动位移控制进行夹取力控制的柔性机械手,基于有限元软件ABAQUS及动力学仿真软件ADAMS,建立了柔性机械手的动力学模型.以不同尺寸的草莓为夹取目标物,对柔性机械手夹取过程进行动力学仿真分析,得到了夹取力随驱动位移量的增加呈线性增加的变化规律,同时获得了驱动速度与瞬时接触夹取力的关系曲线.在此基础上,对柔性机械手样机进行实验分析,结果表明:通过控制驱动位移量及速度进给,机械手能够实现对目标物草莓的无损夹取.该柔性机械手基于柔顺机构特性,无需复杂的传感反馈系统,即可实现对浆果类易损果实的快速抓取,为农业自动化收获机器人末端装置设计提供了一个新思路.

The flexible manipulator is designed and studied based on that the clamping force controlled by the position control in this paper.Based on the finite element software ABAQUS and dynamic simulation software ADAMS,a dynamic simulation model of the flexible manipulator is established.Different sizes of strawberry are used as the object of analysis,the dynamic simulation analysis of the clamping process of the flexible manipulator is carried out,and the change rule that the clamping force increases linearly with the increase of the driving displacement is obtained.At the same time,the relationship between the driving speed and the instantaneous contact clamping force is also obtained based on the dynamic simulation analysis.On this basis,the prototype of the flexible manipulator is produced,and experiment analysis of clamping process of the flexible manipulator is carried out.The results show that:the flexible manipulator can be achieved nondestructive clamping for fragile strawberry by controlling the displacement and drive speed.Therefore the flexible manipulator can realize clamping of the vulnerable fruit quickly without complex sensing and feedback system based on the compliant mechanism characteristics,which provides a new idea for the design of agricultural automation harvesting robot’s end device.