三指机器人手爪设计与抓取研究

Study on Design and Grasping of Three-Finger Robot Hand

传统的多指仿人灵巧手虽然已实现较高的灵巧性与仿人性,但存在设计制作繁琐或价格昂贵以及手指末端抓力偏弱的弊端。而三指机械手作为一种简化形式一般又存在灵巧性不高的问题。针对以上弊端设计了一款基于滑块-摇杆机构的三指机器人手爪。将该结构直接类比人手所设计的手指关节能够实现中节指骨与远节指骨的耦合运动,且指尖力会随手指弯曲程度的增加而增大,有利于对细小目标物进行指尖捏取;采取与传统偏航-俯仰型不同的翻滚-俯仰型掌指结构,在增加了沿掌根关节的旋转自由度的同时尽可能地丰富了手爪的抓取姿态,使其能够适应更多的目标物,增加了灵巧性。在MATLAB中建立手指运动学模型并求得手指末端工作空间。经由实验验证得出该手爪具备较大的抓取力与丰富的抓取姿态。

At present,although the traditional multi-fingering humanoid dexterous hand has achieved high dexterity and humanoid imitation,it has the disadvantages of cumbersome design or expensive and weak grip at the end of the finger.As a simplified method,the three-finger robot hand generally has the problem of low dexterity.A three-finger robot hand based on slider-rocker mechanism is designed.The coupling motion of middle phalanx and distal phalanx can be realized by directly comparing the structure with the finger joint designed by human hand,and the fingertip force will increase with the increase of finger curvature,which is beneficial for fingertip pinching of small objects.Different from the traditional yaw-pitch type,the wrist-pitch type palm-finger structure is designed to enrich the grasping posture of the claw as much as possible while increasing the rotational freedom along the palmar-root joint,so that it can adapt to more targets and increase its dexterity.The kinematics model of finger is established in MATLAB and the working space of finger end is obtained.The experimental results show that the hand has large grasping force and rich grasping posture.