Anthropomorphic flexible joint design and simulation

In this paper, a two-degree-of-freedom (DOF) anthropomorphic pneumatic flexible joint is designed by using a silicone based hyperelastic material. The flexible joint consists of three chambers, which are distributed at 120 degrees, and they are not connected with each other. The pneumatic flexible joint is controlled by inflating high pressure gas to its chambers. Bending properties and motion space of the pneumatic flexible joint is analysed. And the influence of the chambers’ sizes and intervals on the joint’s curvature and motion space is analyzed through a series of finite element models (FEMs). Finally, the design of the geometrical sizes of the pneumatic flexible joint is studied qualitatively. Finite element analysis (FEA), under gas pressure of 10 kPa, 15 kPa, 20 kPa and 25 kPa, respectively, showes that the designed structure could realize two-degree-offreedom motion of the pneumatic flexible joint, which makes up for the deficiency of traditional one-degree-of-freedom pneumatic flexible joints.