Abstract: Aiming at the problems of exoskeleton robots in terms of bio-imitability and portability,as well as the lack of research on the internal and external rotation motion of the third degree of freedom of the wrist,a wearable wrist flexible exoskeleton device was designed based on Shape Memory Alloy (SMA) actuation based on analyses of the mechanism of muscle movement during internal and external rotation motion of the wrist driven by the forearm. A biomechanically compliant exoskeleton device was designed using 3D software based on the mechanism of the pronator teres,musculus pronator quadratus,and supinator muscles in the anatomical structure of the human forearm,which is driven by SMA springs to achieve the internal and external rotation movement of the wrist. The biomimetic and flexible nature of this exoskeleton device is in line with the human wrist movement characteristics,and its light weight and convenience can effectively assist the patients with hand function deficiency to complete more flexible daily life activities,which provides new perspectives and methods in the field of hand function rehabilitation medical treatment.

Key words: Shape Memory Alloy (SMA), internal and external rotational movements, functional hand rehabilitation, bionic exoskeleton, Vicon motion capture