主被动复合驱动自适应指爪机构的抓取模式分析  

Gripping Mode Analysis of an Active-Passive Composited Driving Self-adaptive Gripper Mechanism

作　　者：楚中毅[1,2] 周苗[1,2] 胡健[1,2] 卢山[3] 

机构地区：[1]北京航空航天大学仪器科学与光电工程学院,北京100191 [2]北京航空航天大学惯性技术重点实验室,北京100191 [3]上海航天技术研究院,上海201109

出　　处：《航空学报》2014年第12期3451-3458,共8页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(51375034;61327809)~~

摘　　要：为了满足空间在轨服务任务的多样化需求,基于主被动复合驱动思想提出一种自适应末端操作器——二指连杆欠驱动指爪机构,并对其抓取模式进行定量分析。首先,在描述指爪机构运动学关系的基础上,根据虚功原理建立机构的静力平衡方程。在此基础上,对其进行静力学分析可知,机构平衡状态下与目标物的接触力不仅取决于机构的几何尺寸,还与接触点位置有关;而机构的抓取模式取决于约束空间内系统的受力情况,因此该指爪能够根据不同形状目标物与机构接触点位置的不同,自适应地选择抓取模式,包括平行抓取、包络抓取等。最后,通过实验样机对不同形状物体进行抓取实验,验证了指爪机构抓取目标的自适应性,为后续的机构设计和控制应用奠定理论和技术基础。To meet the need of diverse tasks during on-orbit service,a self-adaptive end effector based on an active-passive composited driver is proposed,which is a two-finger underactuated gripper.This paper focuses on the gripping mode analysis of the proposed gripper.Firstly,the kinematics of the gripper is explained.Secondly,the static equilibrium conditions are deduced from the input and the output virtual powers.Known from the statics,the contact forces in the equilibrium state between the gripper and the object rely not only on the geometrical configuration,but also on the contact locations.While the gripping mode of gripper depends on the contact forces in the constraint space,it leads to the mechanical adaptation of the gripper to the shape of the object based on different contact locations,resulting in different gripping modes,including parallel grip,encompassing grip.Finally,an experimental setup is implemented to analyze the capture process of the gripper towards different shaped objects,and the results validate the self-adaptability of the active-passive composited driving gripper,which lays the foundation for mechanical design and control strategy in future work.

关 键 词：指爪机构 主被动复合驱动 抓取模式 静力学 自适应性 

分 类 号：V448.222[航空宇航科学与技术—飞行器设计] TH133.5[机械工程—机械制造及自动化]