Design of human-like hand-arm for human-assisted manipulation

Abstract

A hand-arm system is an important module on a humanoid robot. It enables a humanoid

robot to perform grasping and manipulation for many applications such as providing

helps to elderly people. However, owing to limited space and weight, most humanoid

robots are equipped with simple hand-arm systems, in which the hands have much lesser

degrees of freedom than a human being’s hands. Therefore, it is a challenge to design and implement a robotic hand-arm system which is similar to that of a human being. In this project, a human-like hand-arm system is designed and implemented. The hand has 6 independent and 4 coupled degrees of freedom (DOFs) for its five fingers and the arm

has 6 DOFs. In the design of human-like hand, each finger is assigned 2 DOFs. In this

way, a hand will have 10 DOFs. However, in order to achieve the requirement of compact

size, only six DOFs are actuated, and the other four DOFs will be coupled to the actuated

DOFs. To realize such joint couplings, four bar linkage and rack-pinion structure are

adopted.