腱绳驱动机械手的设计及其柔性抓取控制  

Design and flexible grasp control of tendon-driven mechanical gripper

作　　者：徐光宇 汤卿[1] 王丽霞 XU Guangyu;TANG Qing;WANG Lixia(School of Mechanical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学机械工程学院,四川成都610065

出　　处：《机电工程》2023年第10期1550-1557,共8页Journal of Mechanical & Electrical Engineering

基　　金：四川省科技计划项目(2021YFG0074)。

摘　　要：为了实现机械手稳定的自适应抓取目的,需要加强对抓取信息的感知处理,同时设计柔顺的力控抓取算法。针对不同尺寸、外形、材质的物体对抓取姿态和力度要求各异的问题,提出了一种腱绳驱动的柔性三指机械手方案及对应的柔性抓取力控算法(导纳力控算法)。首先,设计了一种腱绳驱动柔性机械手指,提出了一种往复式缠绕的腱绳传动线路,制作了柔性机械手的实物;其次,采用改进Denavit-Hartenberg(DH)法,建立了机械手指的运动学模型,利用MATLAB的机器人工具箱,分析了手指的自适应包络能力;然后,设计了适配机械手驱动的导纳控制算法,通过在实物上的程序实现和控制测试对机械手的柔性力控性能进行了验证;最后,搭建了柔性机械手的软件控制平台和实机实验平台,对不同目标物体进行了实物抓取实验,对柔性机械手的稳定抓取能力进行了验证。研究结果表明:该往复式缠绕传动线路和导纳力控算法可保证该机械手在面对不同尺寸、外形、材质的物体时,具有抓取形状的高自适应性和抓取力的高柔顺性;在抓取过程中,机械手的手指可以自适应地包络目标,并借助导纳控制算法柔顺地控制抓取力,进而完成稳定、可靠的抓取任务。In order to achieve the goal of stable adaptive grasping of manipulator,it is necessary to strengthen the perceptual processing of grasping information and design a flexible force-controlled grasping algorithm.Aiming at the problem that objects of different sizes,shapes,and materials require diverse grasping postures and strengths,a tendon-driven flexible three-fingered mechanical gripper scheme and corresponding flexible grasping force control algorithm(admittance control algorithm)were proposed.Firstly,a tendon-driven flexible mechanical finger was designed,and a reciprocating winding designed tendon-driven transmission line was proposed.An actual flexible three-fingered mechanical gripper was fabricated based on this design.Secondly,the modified Denavit-Hartenberg(DH)method was used to establish the kinematic model of the flexible mechanical fingers,and the adaptive enveloping ability of the fingers was analyzed using MATLAB robotics toolbox.Then,an admittance control algorithm was designed according to the characteristics of the servo motor,and the flexible force control performance of the mechanical gripper was tested through physical program implementation and admittance control experiment.Finally,a software control platform and a physical experiment platform were built for the flexible mechanical gripper,and gripping experiments were carried out on objects of various shapes and materials to verify the stable and reliable grasping of the flexible mechanical gripper.The research results indicate that the reciprocating winding transmission line design and the corresponding flexible admittance control algorithm ensure high adaptability of grasping shape and high flexibility of grasping force when the flexible mechanical gripper faces objects of varying sizes,shapes,and materials.During the grasping process,the fingers of the flexible mechanical gripper can adaptively envelop the target object and control the grasping force smoothly through the admittance control algorithm.This enables the mechanical gripper to

关 键 词：机械手指 腱绳驱动 自适应抓取 导纳控制算法 柔性抓取 往复式缠绕传动线路 Denavit-Hartenberg 

分 类 号：TH-39[机械工程] TP241.2[自动化与计算机技术—检测技术与自动化装置]