I. Introduction
Soft-bodied robotic system have improved wearable power devices for gait assistance, which have been developed for rehabilitation training by patients with gait disorders [1]. Softness of the devices increased the safety of the assisting system, and their lightness of the weight decreased physical burden to trainees. As a key technology, pneumatic soft actuators, such as pneumatic artificial muscles (PAMs), have been used in some soft assistive suits because of their intrinsic softness and lightness of the weight [2] [3].