Variable viscoelastic joint system and its application to exoskeleton

Abstract

In this study, a variable viscoelastic joint system comprising antagonized artificial muscles and magneto-rheological fluid brakes is proposed. This system enables human assisting devices such as robotic exoskeletons to retain structural softness when compared with the existing devices driven by motors and reduction gears, which can only achieve superficial softness. The authors had proposed the system and showed its effectiveness via experiments using a prototype with one degree of freedom in their previous works. In this study, as the next step in designing the human assisting device, a lower body assistive prototype “Airsist” is introduced. In addition, a control method that can cooperate with the wearer without the need for an additional operation is proposed.